Breast Cancer Treatment (PDQ®)
Purpose of This PDQ Summary
This PDQ cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the treatment of breast cancer. This summary is reviewed regularly and updated as necessary by the PDQ Adult Treatment Editorial Board.
Information about the following is included in this summary:
- Genetic characteristics and risk factors.
- Prognostic factors.
- Cellular classification.
- Staging.
- Treatment options by cancer stage.
This summary is intended as a resource to inform and assist clinicians who care for cancer patients. It does not provide formal guidelines or recommendations for making health care decisions.
Some of the reference citations in the summary are accompanied by a level-of-evidence designation. These designations are intended to help readers assess the strength of the evidence supporting the use of specific interventions or approaches. The PDQ Adult Treatment Editorial Board uses a formal evidence ranking system in developing its level-of-evidence designations. Based on the strength of the available evidence, treatment options are described as either “standard” or “under clinical evaluation.” These classifications should not be used as a basis for reimbursement determinations.
This summary is available in a patient version, written in less technical language, and in Spanish.
General Information About Breast Cancer
This summary discusses only
primary epithelial breast cancers. Rarely, the breast may be involved by other
tumors such as lymphomas, sarcomas, or melanomas. (Refer to the PDQ summaries on Adult Hodgkin Lymphoma Treatment, Adult Soft Tissue Sarcoma Treatment, and Melanoma Treatment for more information.)
Note: Some citations in the text of this section are followed by a level of
evidence. The PDQ editorial boards use a formal ranking system to help the
reader judge the strength of evidence linked to the reported results of a
therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more
information.)
Related Summaries
Other PDQ summaries containing information related to breast cancer include:
Statistics
Note: Estimated new cases and deaths from breast cancer (women only) in the United States in 2009:
- New cases: 192,370.
- Deaths: 40,170.
Genetic Characteristics and Risk Factors
Several well-established factors have been associated with an increased risk of
breast cancer, including family history, nulliparity, early menarche,
advanced age, and a personal history of breast cancer (in situ or invasive).
Age-specific risk estimates are available to help counsel and design
screening strategies for women with a family history of breast cancer. Of all women with breast cancer, 5% to 10% may have a germ-line
mutation of the genes BRCA1 and BRCA2. Specific mutations of BRCA1 and
BRCA2 are more common in women of Jewish ancestry. The estimated lifetime
risk of developing breast cancer for women with BRCA1 and BRCA2 mutations is
40% to 85%. Carriers with a history of breast cancer have an increased risk of
contralateral disease that may be as great as 5% per year. Male carriers of
BRCA2 mutations are also at increased risk for breast cancer.
Mutations in
either the BRCA1 or BRCA2 gene also confer an increased risk of ovarian cancer. In
addition, mutation carriers may be at increased risk of other primary
cancers. Genetic testing is available to detect mutations in members of
high-risk families. Such individuals should first be referred for
counseling. (Refer to the PDQ summaries on Genetics of Breast and Ovarian Cancer; Breast Cancer Prevention; and Breast Cancer Screening for more
information.)
Screening
Clinical trials have established that screening with mammography, with or
without clinical breast examination, may decrease breast cancer mortality.
(Refer to the PDQ summary on Breast Cancer Screening for more information.)
Patient Evaluation
Patient management following initial suspicion of breast cancer generally
includes confirmation of the diagnosis, evaluation of stage of disease, and
selection of therapy. At the time the tumor tissue is surgically removed, estrogen receptor (ER) and progesterone receptor (PR) status
should be determined.
Prognostic Factors
Breast cancer is commonly treated by various combinations of surgery, radiation
therapy, chemotherapy, and hormone therapy. Prognosis and selection of therapy
may be influenced by:
- The age and menopausal status of the patient.
- The stage of the
disease.
- The histologic and nuclear grade of the primary tumor.
- The ER and PR status of the tumor.
- The measures of proliferative capacity of the tumor.
- HER2/neu gene amplification.
Although certain rare inherited mutations
such as those of BRCA1 and BRCA2 predispose women to develop breast cancer, prognostic
data on mutation carriers who have developed breast cancer are conflicting.
Since criteria for menopausal status vary widely, some studies have substituted
age older than 50 years as a surrogate for the postmenopausal state. Breast
cancer is classified into a variety of histologic types, some of which have
prognostic importance. For example, favorable histologic types include
mucinous, medullary, and tubular carcinoma.
Contralateral Disease
Pathologically, breast cancer can be a multicentric and bilateral disease.
Bilateral disease is somewhat more common in patients with infiltrating lobular
carcinoma. Patients who have breast cancer should have bilateral
mammography at the time of diagnosis to rule out synchronous disease. The role of magnetic resonance imaging (MRI) in screening and follow-up continues to evolve. Having demonstrated an increased detection rate of mammographically occult disease, the selective use of MRI for additional screening is being used with increased frequency despite the absence of randomized, controlled data. Because only 25% of MRI-positive findings represent malignancy, pathologic confirmation prior to treatment action is recommended. Whether this increased detection rate will translate into improved treatment outcome is unknown.
Patients
should continue to have regular breast physical examinations and mammography to
detect either recurrence in the ipsilateral breast in those patients treated
with breast-conserving surgery or a second primary cancer in the contralateral
breast. The risk of a primary breast cancer in the contralateral breast is
approximately 1% per year. Patient age younger than 55 years at the time
of diagnosis or lobular tumor histology appear to increase this risk to
1.5%. The development of a contralateral breast cancer is associated with
an increased risk of distant recurrence.
Hormone Replacement Therapy
The use of hormone replacement therapy (HRT) poses a dilemma for the rising
numbers of breast cancer survivors, many of whom enter menopause prematurely as
a result of therapy. HRT has generally not been used for women with a history
of breast cancer because estrogen is a growth factor for most breast cancer
cells in the laboratory; however, empiric data on the safety of HRT after breast cancer are limited.
Two randomized trials (including Regional Oncologic Center-Hormonal Replacement Therapy After Breast Cancer--Is It Safe [ROC-HABITS]) comparing HRT with no hormonal supplementation have been reported. The first trial included 345 evaluable breast cancer patients with menopausal symptoms and was terminated early because of an increased incidence of recurrences and new primaries in the HRT group (hazard ratio [HR] = 3.5; 95% confidence interval [CI], 1.5–7.4).[Level of evidence: 1iiDii] In total, 26 women in the HRT group and 7 in the non-HRT group developed recurrences or new primaries. This study, however, was not double blinded, and it is possible that patients on HRT were monitored more closely. Because of the results of the first trial, the second trial, which was conducted under a joint steering committee with the first, closed prematurely after the enrollment of 378 patients. With a median follow-up of 4.1 years, there were 11 recurrences in the hormone replacement group and 13 recurrences in the patients assigned to no hormone replacement (HR = 0.82; 95% CI, 0.35–1.9).[Level of evidence: 1iiDii] The trials differed in several ways; however, until further data become available, decisions concerning the use of HRT in patients with breast cancer will have to be based on the results of these studies and on inferences from the impact of HRT use on breast cancer risk in other settings. A comprehensive intervention,
including education, counseling, and nonhormonal drug therapy, has been shown
to reduce menopausal symptoms and to improve sexual functioning in breast
cancer survivors.[Level of evidence: 1iiC]
(For more information, refer to the PDQ summaries on Fever, Sweats, and Hot Flashes and Sexuality and Reproductive Issues.)
Breast Reconstruction
For patients who opt for a total mastectomy, reconstructive surgery may be
used at the time of the mastectomy (immediate reconstruction)
or at some subsequent time (delayed reconstruction). Breast contour can
be restored by the submuscular insertion of an artificial implant
(saline-filled) or a rectus muscle or other flap. If a saline implant is used,
a tissue expander can be inserted beneath the pectoral muscle. Saline is
injected into the expander to stretch the tissues for a period of weeks or
months until the desired volume is obtained. The tissue expander is
replaced by a permanent implant. (Visit the FDA's Web site for more
information on breast implants.) Rectus muscle flaps require a
considerably more complicated and prolonged operative procedure, and blood
transfusions may be required.
Following breast reconstruction, radiation
therapy can be delivered to the chest wall and regional nodes either in the
adjuvant setting or if local disease recurs. Radiation therapy following
reconstruction with a breast prosthesis may affect cosmesis, and the incidence
of capsular fibrosis, pain, or the need for implant removal may be
increased.
Follow-up
Evidence from randomized trials indicates that periodic follow-up with bone
scans, liver sonography, chest x-rays, and blood tests of liver function does not
improve survival or quality of life when compared to routine physical
examinations. Even when these tests permit earlier detection of
recurrent disease, patient survival is unaffected. Based on these data,
some investigators recommend that acceptable follow-up be limited to physical
examination and annual mammography for asymptomatic patients who complete
treatment for stage I to stage III breast cancer. The frequency of follow-up and the
appropriateness of screening tests after the completion of primary treatment
for stage I to stage III breast cancer remain controversial.
Cellular Classification of Breast Cancer
The following is a list of breast cancer histologic classifications.
Infiltrating or invasive ductal cancer is the most common breast cancer
histologic type and comprises 70% to 80% of all cases.
- Carcinoma, NOS (not otherwise specified).
- Ductal.
- Intraductal (in situ).
- Invasive with predominant intraductal component.
- Invasive, NOS.
- Comedo.
- Inflammatory.
- Medullary with lymphocytic infiltrate.
- Mucinous (colloid).
- Papillary.
- Scirrhous.
- Tubular.
- Other.
- Lobular.
- In situ.
- Invasive with predominant in situ component.
- Invasive.
- Nipple.
- Paget disease, NOS.
- Paget disease with intraductal carcinoma.
- Paget disease with invasive ductal carcinoma.
- Other.
- Undifferentiated carcinoma.
The following are tumor subtypes that occur in the breast but are not
considered to be typical breast cancers:
- Phyllodes tumor.
- Angiosarcoma.
- Primary lymphoma.
Stage Information for Breast Cancer
The American Joint Committee on Cancer (AJCC) staging system provides a
strategy for grouping patients with respect to prognosis. Therapeutic
decisions are formulated in part according to staging categories but primarily
according to tumor size, lymph node status, estrogen-receptor and progesterone-receptor
levels in the tumor tissue, human epidermal growth factor receptor 2 (HER2/neu) status, menopausal status, and the general health of the
patient.
The AJCC has designated staging by TNM classification. This system was modified in 2002 and classifies some nodal categories as stage III that were previously considered stage II. As a result of the stage migration phenomenon, survival by stage for case series classified by the new system will appear superior to those using the old system.
TNM Definitions
Definitions for classifying the primary tumor (T) are the same for clinical and for pathologic classification. If the measurement is made by physical examination, the examiner will use the major headings (T1, T2, or T3). If other measurements, such as mammographic or pathologic measurements, are used, the subsets of T1 can be used. Tumors should be measured to the nearest 0.1 cm increment.
Primary tumor (T)
- TX: Primary tumor cannot be assessed
-
T0: No evidence of primary tumor
- Tis: Intraductal carcinoma, lobular carcinoma in situ, or Paget disease of the nipple with no associated invasion of normal breast tissue
- Tis (DCIS): Ductal carcinoma in situ
- Tis (LCIS): Lobular carcinoma in situ
- Tis (Paget): Paget disease of the nipple with no tumor. Paget disease associated with a tumor is classified according to the size of the tumor.
- T1: Tumor not larger than 2.0 cm in greatest dimension
- T1mic: Microinvasion not larger than 0.1 cm in greatest dimension
- T1a: Tumor larger than 0.1 cm but not larger than 0.5 cm in greatest dimension
- T1b: Tumor larger than 0.5 cm but not larger than 1.0 cm in greatest dimension
- T1c: Tumor larger than 1.0 cm but not larger than 2.0 cm in greatest dimension
- T2: Tumor larger than 2.0 cm but not larger than 5.0 cm in greatest dimension
- T3: Tumor larger than 5.0 cm in greatest dimension
-
T4: Tumor of any size with direct extension to (a) chest wall or (b) skin,
only as described below
- T4a: Extension to chest wall, not including pectoralis muscle
- T4b: Edema (including peau d’orange) or ulceration of the skin of the
breast, or satellite skin nodules confined to the same breast
- T4c: Both T4a and T4b
- T4d: Inflammatory carcinoma
Regional lymph nodes (N)
- NX: Regional lymph nodes cannot be assessed (e.g., previously removed)
- N0: No regional lymph node metastasis
- N1: Metastasis to movable ipsilateral axillary lymph node(s)
- N2: Metastasis to ipsilateral axillary lymph node(s) fixed or matted, or in clinically apparent* ipsilateral internal mammary nodes in the absence of clinically evident lymph node metastasis
- N2a: Metastasis in ipsilateral axillary lymph nodes fixed to one another (matted) or to other structures
- N2b: Metastasis only in clinically apparent* ipsilateral internal mammary nodes and in the absence of clinically evident axillary lymph node metastasis
- N3: Metastasis in ipsilateral infraclavicular lymph node(s) with or without axillary lymph node involvement, or in clinically apparent* ipsilateral internal mammary lymph node(s) and in the presence of clinically evident axillary lymph node metastasis; or, metastasis in ipsilateral supraclavicular lymph node(s) with or without axillary or internal mammary lymph node involvement
- N3a: Metastasis in ipsilateral infraclavicular lymph node(s)
- N3b: Metastasis in ipsilateral internal mammary lymph node(s) and axillary lymph node(s)
- N3c: Metastasis in ipsilateral supraclavicular lymph node(s)
*Clinically apparent is defined as detected by imaging studies (excluding lymphoscintigraphy) or by clinical examination or grossly visible pathologically.
Pathologic classification (pN)*
- pNX: Regional lymph nodes cannot be assessed (e.g., not removed for pathologic
study or previously removed)
- pN0: No regional lymph node metastasis histologically, and no additional examination for isolated tumor cells (ITC)
ITCs are defined as single tumor cells or small cell clusters not larger than 0.2 mm, usually detected only by immunohistochemical (IHC) or molecular methods but that may be verified on hematoloxylin & eosin (H&E) stains. ITCs do not usually show evidence of malignant activity, e.g., proliferation or stromal reaction.
- pN0(i-): No regional lymph node metastasis histologically, negative IHC
- pN0(i+): No regional lymph node metastasis histologically, positive IHC, and no IHC cluster larger than 0.2 mm
- pN0(mol-): No regional lymph node metastasis histologically, and negative molecular findings (RT-PCR)**
- pN0(mol+): No regionally lymph node metastasis histologically, and positive molecular findings (RT-PCR)**
*Classification is based on axillary lymph node dissection with or without sentinel lymph node (SLN) dissection. Classification based solely on SLN dissection without subsequent axillary lymph node dissection is designated (sn) for sentinel node, e.g., pN0(I+) (sn). **RT-PCR: reverse transcriptase-polymerase chain reaction.
- pN1: Metastasis in one to three axillary lymph nodes, and/or in internal mammary nodes with microscopic disease detected by SLN dissection but not clinically apparent**
- pN1mi: Micrometastasis (larger than 0.2 mm but not larger than 2.0 mm)
- pN1a: Metastasis in one to three axillary lymph nodes
- pN1b: Metastasis in internal mammary nodes with microscopic disease detected by SLN dissection but not clinically apparent**
- pN1c: Metastasis in one to three axillary lymph nodes and in internal mammary lymph nodes with microscopic disease detected by SLN dissection but not clinically apparent** (If associated with more than three positive axillary lymph nodes, the internal mammary nodes are classified as pN3b to reflect increased tumor burden.)
- pN2: Metastasis in four to nine axillary lymph nodes, or in clinically apparent ** internal mammary lymph nodes in the absence of axillary lymph node metastasis to ipsilateral axillary lymph node(s) fixed to each other
or to other structures
- pN2a: Metastasis in four to nine axillary lymph nodes (at least one tumor deposit larger than 2.0 mm)
- pN2b: Metastasis in clinically apparent* internal mammary lymph nodes in the absence of axillary lymph node metastasis
- pN3: Metastasis in ten or more axillary lymph nodes, or in infraclavicular lymph nodes, or in clinically apparent* ipsilateral internal mammary lymph node(s)
in the presence of one or more positive axillary lymph node(s); or, in more than three axillary lymph nodes with clinically negative microscopic metastasis in internal mammary lymph nodes; or, in ipsilateral supraclavicular lymph nodes
- pN3a: Metastasis in ten or more axillary lymph nodes (at least one tumor deposit larger than 2.0 mm); or, metastasis to the infraclavicular lymph nodes
- pN3b: Metastasis in clinically apparent* ipsilateral internal mammary lymph nodes in the presence of one or more positive axillary lymph node(s); or, in more than three axillary lymph nodes and in internal mammary lymph nodes with microscopic disease detected by sentinel lymph node dissection but not clinically apparent**
- pN3c: Metastasis in ipsilateral supraclavicular lymph nodes
*Clinically apparent is defined as detected by imaging studies (excluding lymphoscintigraphy) or by clinical examination.
**Not clinically apparent is defined as not detected by imaging studies (excluding lymphoscintigraphy) or by clinical examination.
Distant metastasis (M)
- MX: Presence of distant metastasis cannot be assessed
- M0: No distant metastasis
- M1: Distant metastasis
AJCC Stage Groupings
Stage 0
Stage I
Stage IIA
- T0, N1, M0
- T1*, N1, M0
- T2, N0, M0
Stage IIB
Stage IIIA
- T0, N2, M0
- T1*, N2, M0
- T2, N2, M0
- T3, N1, M0
- T3, N2, M0
Stage IIIB
- T4, N0, M0
- T4, N1, M0
- T4, N2, M0
Stage IIIC**
Stage IV
*T1 includes T1mic.
**Stage IIIC breast cancer includes patients with any T stage who have pN3 disease. Patients with pN3a and pN3b disease are considered operable and are managed as described in the section on Stage I, II, IIIA, and operable IIIC breast cancer. Patients with pN3c disease are considered inoperable and are managed as described in the section on Inoperable stage IIIB or IIIC or inflammatory breast cancer.
Ductal Carcinoma In Situ
Note: Some citations in the text of this section are followed by a level of
evidence. The PDQ editorial boards use a formal ranking system to help the
reader judge the strength of evidence linked to the reported results of a
therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more
information.)
Introduction
Ductal carcinoma in situ (DCIS) is a noninvasive condition. DCIS can progress to become invasive cancer, but estimates of the likelihood of this vary widely. Some people include DCIS in breast cancer statistics. The frequency of the diagnosis of DCIS has increased markedly in the United States since the widespread use of screening mammography. In 1998, DCIS accounted for about 18% of all newly diagnosed invasive plus noninvasive breast tumors in the United States.
Very few cases of DCIS present as a palpable mass;
80% are diagnosed by mammography alone. DCIS comprises a heterogeneous
group of histopathologic lesions that have been classified into several
subtypes based primarily on architectural pattern: micropapillary, papillary,
solid, cribriform, and comedo. Comedo-type DCIS consists of cells that appear
cytologically malignant, with the presence of high-grade nuclei,
pleomorphism, and abundant central luminal necrosis. Comedo-type DCIS appears
to be more aggressive, with a higher probability of associated invasive ductal
carcinoma.
Treatment Option Overview
Until recently, the customary treatment of DCIS was mastectomy. The
rationale for mastectomy included a 30% incidence of multicentric disease, a
40% prevalence of residual tumor at mastectomy following wide excision alone,
and a 25% to 50% incidence of breast recurrence following limited surgery for
palpable tumor, with 50% of those recurrences being invasive carcinoma.
The combined local and distant recurrence rate following mastectomy is 1% to
2%.
No randomized comparisons of mastectomy versus breast-conserving surgery plus breast radiation are available.
In view of the success of breast-conserving surgery combined with breast radiation for invasive carcinoma, this conservative approach was extended to the noninvasive entity. To determine whether breast-conserving surgery plus radiation therapy was a reasonable approach to the management of DCIS, the National Surgical Adjuvant Breast and Bowel Project (NSABP) and the European Organisation for Research and Treatment of Cancer (EORTC) have each completed prospective randomized trials in which women with localized DCIS and negative surgical margins following excisional biopsy were randomized to either breast radiation (50 Gy) or to no further therapy.
Of the 818 women enrolled in the NSABP B-17 trial, 80% were diagnosed by mammography, and 70% of the patients' lesions were 1 cm or less. At the 12-year actuarial follow-up interval, the overall rate of in-breast tumor recurrence was reduced from 31.7% to 15.7% when radiation therapy was delivered (P < .005). Radiation therapy reduced the occurrence of invasive cancer from 16.8% to 7.7% (P = .001) and recurrent DCIS from 14.6% to 8.0% (P = .001).[Level of evidence: 1iiDii] Nine pathologic features were evaluated for their ability to predict for in-breast recurrence, but only comedo necrosis was determined to be a significant predictor for recurrence.
Similarly, of the 1,010 patients enrolled in the EORTC-10853 trial, mammography detected lesions in 71% of the women. At a median follow-up of 10.5 years, the overall rate of in-breast tumor recurrence was reduced from 26% to 15% (P < .001) with a similarly effective reduction of invasive (13% to 8%, P = .065) and noninvasive (14% to 7%, P = .001) recurrence rates.[Level of evidence: 1iiDii] In this analysis, parameters associated with an increased risk of in-breast recurrence included age 40 years or younger, palpable disease, intermediate or poorly differentiated DCIS, cribriform or solid growth pattern, and indeterminate margins. Elsewhere, margins of less than 1 mm have been associated with an unacceptable local recurrence rate, even with radiation therapy. In both of the studies reported here, the effect of radiation therapy was consistent across all assessed risk factors.
Given that lumpectomy and radiation therapy are generally applicable for most
patients with DCIS, can a subset of patients be identified with such a low risk
of local recurrence that postoperative radiation therapy can be omitted? To identify such a favorable group of patients, several pathologic
staging systems have been developed and tested retrospectively, but consensus
recommendations have not been achieved. The Van Nuys Prognostic Index, which combines three predictors of local recurrence (i.e., tumor size, margin
width, and pathologic classification), was used to retrospectively analyze 333
patients treated with either excision alone or excision and radiation
therapy. Using this prognostic index, patients with favorable lesions, who
received surgical excision alone, had a low recurrence rate (i.e., 2% with a median
follow-up of 79 months). A subsequent analysis of these data was performed to
determine the influence of margin width on local control. Patients whose
excised lesions had margin widths 10 mm or larger in every direction
had an extremely low probability of local recurrence with surgery alone (4%
with a mean follow-up of 8 years). These reviews
are retrospective, noncontrolled, and are subject to substantial selection
bias. By contrast, no subset of patients was identified in the
prospective NSABP trial that did not benefit from the addition of radiation
therapy to lumpectomy in the management of DCIS.
To determine if tamoxifen adds to the efficacy of local
therapy in the management of DCIS, the NSABP performed a double-blind
prospective trial (NSABP-B24) of 1,804 women. Patients were randomly assigned to
lumpectomy, radiation therapy (50 Gy), and placebo versus lumpectomy, radiation
therapy, and tamoxifen (20 mg/day for 5 years). Positive or unknown
surgical margins were present in 23% of patients. Approximately 80% of the
lesions measured not larger than 1 cm, and more than 80% were detected
mammographically. Breast cancer events were defined as the presence of new
ipsilateral disease, contralateral disease, or metastases. Women in the
tamoxifen group had fewer breast cancer events at 5 years than did those on a
placebo (8.2% vs. 13.4%; P = .009).[Level of evidence: 1iDii] With
tamoxifen, ipsilateral invasive breast cancer decreased from 4.2% to 2.1% at 5
years (P = .03). Tamoxifen also decreased the incidence of contralateral breast
neoplasms (invasive and noninvasive) from 0.8% per year to 0.4% per year
(P = .01). The benefit of tamoxifen extended to those patients with positive or
uncertain margins. (Refer to the PDQ summary on Breast Cancer Prevention
for more information.)
Treatment Options for Patients with DCIS
- Breast-conserving surgery and radiation therapy with or without tamoxifen.
- Total mastectomy with or without tamoxifen.
- Breast-conserving surgery without radiation therapy. A large national
clinical trial by the Radiation Therapy Oncology Group (RTOG-9804) comparing breast-conserving surgery and tamoxifen with or
without radiation therapy was closed due to poor accrual and results are pending.
Current Clinical Trials
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with
ductal breast carcinoma in situ. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Lobular Carcinoma In Situ
Introduction
The term lobular carcinoma in situ (LCIS) is misleading. This lesion is more
appropriately termed lobular neoplasia. Strictly speaking, it is not known
to be a premalignant lesion, but rather a marker that identifies women at an
increased risk for subsequent development of invasive breast cancer. This risk
remains elevated even beyond 2 decades, and most of the subsequent cancers are
ductal rather than lobular. LCIS is usually multicentric and is frequently
bilateral. In a large prospective series from the National Surgical Adjuvant
Breast and Bowel Project with a 5-year follow-up of 182 women with LCIS
managed with excisional biopsy alone, only eight women developed ipsilateral breast
tumors (four of the tumors were invasive). In addition, three women developed contralateral breast
tumors (two of the tumors were invasive).
Treatment Option Overview
Most women with LCIS have disease that can be managed without additional local therapy after
biopsy. No evidence is available that re-excision to obtain clear margins is
required. The use of tamoxifen has decreased the risk of developing breast
cancer in women with LCIS and should be considered in the routine management of
these women. The NSABP-P1trial of 13,388 high-risk
women comparing tamoxifen to placebo demonstrated an overall 49% decrease in
invasive breast cancer, with a mean follow-up of 47.7 months. Risk was
reduced by 56% in the subset of 826 women with a history of LCIS, and the
average annual hazard rate for invasive cancer fell from 12.99 per 1,000 women
to 5.69 per 1,000 women. In women older than 50 years, this benefit was
accompanied by an annual incidence of 1 to 2 per 1,000 women of endometrial
cancer and thrombotic events. (Refer to the PDQ summary on
Breast Cancer Prevention for more information.)
Bilateral prophylactic mastectomy is sometimes considered an
alternative approach for women at high risk for breast cancer. Many
breast surgeons, however, now consider this to be an overly aggressive approach.
Axillary lymph node dissection is not necessary in the management of LCIS.
Treatment Options for Patients with LCIS
- Observation after diagnostic biopsy.
- Tamoxifen to decrease the incidence of subsequent breast cancers.
- Ongoing breast cancer prevention trials (including the National Cancer Institute of Canada's trial [CAN-NCIC-MAP3], for example).
- Bilateral prophylactic total mastectomy, without axillary node dissection.
Current Clinical Trials
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with
lobular breast carcinoma in situ. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Stage I, II, IIIA, and Operable IIIC Breast Cancer
Note: Some citations in the text of this section are followed by a level of
evidence. The PDQ editorial boards use a formal ranking system to help the
reader judge the strength of evidence linked to the reported results of a
therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more
information.)
Primary Therapy
Local-regional treatment
Stage I, II, IIIA, and operable IIIC breast cancer often requires a multimodality approach to
treatment. Irrespective of the eventual procedure selected, the diagnostic
biopsy and surgical procedure that will be used as primary treatment should be
performed as two separate procedures. In many cases, the diagnosis of breast
carcinoma using core needle biopsy or fine-needle aspiration cytology may be
sufficient to confirm malignancy. After the presence of a malignancy is
confirmed and histology is determined, treatment options should be discussed
with the patient before a therapeutic procedure is selected. The surgeon may
proceed with a definitive procedure that may include biopsy, frozen
section confirmation of carcinoma, and the surgical procedure elected by the
patient. Estrogen-receptor (ER) and progesterone-receptor (PR) protein status
should be determined for the primary tumor. Additional pathologic
characteristics, including grade, proliferative activity, and human epidermal growth factor receptor 2 (HER2/neu) status,
may also be of value.
Options for surgical management of the primary tumor include breast-conserving
surgery plus radiation therapy, mastectomy plus reconstruction, and mastectomy
alone. Surgical staging of the axilla should also be performed. Survival is
equivalent with any of these options as documented in randomized prospective
trials (including the European Organization for Research and Treatment of Cancer's trial [EORTC-10801]). Selection of a local therapeutic approach depends on the
location and size of the lesion, analysis of the mammogram, breast size, and
the patient’s attitude toward preserving the breast. The presence of
multifocal disease in the breast or a history of collagen vascular disease are
relative contraindications to breast-conserving therapy.
All histologic types of invasive breast cancer may be treated with
breast-conserving surgery plus radiation therapy. The rate of local
recurrence in the breast with conservative treatment is low and varies slightly
with the surgical technique used (e.g., lumpectomy, quadrantectomy, segmental
mastectomy, and others). Whether completely clear
microscopic margins are necessary is debatable. Retrospective studies have shown
that certain tumor characteristics, such as large tumors (T2 lesions), positive
axillary nodes, tumors with an extensive intraductal component, palpable
tumors, and lobular histology correlate with a greater likelihood of finding
persistent tumor on re-excision. Patients whose tumors have these
characteristics may benefit from a more generous initial excision to avoid the
need for a re-excision.
Radiation therapy (as part of breast-conserving local therapy) consists of
postoperative external-beam radiation therapy (EBRT) to the entire breast with doses of 45 Gy
to 50 Gy, in 1.8 Gy to 2.0 Gy daily fractions over a 5-week period. Shorter
hypofractionation schemes achieve comparable results. A further radiation
boost is commonly given to the tumor bed. Two randomized trials conducted in
Europe have shown that using boosts of 10 Gy to 16 Gy reduces the risk of local
recurrence from 4.6% to 3.6% at 3 years (P = .044),[Level of evidence: 1iiDiii] and from 7.3% to 4.3% at 5 years (P < .001), respectively.[Level of evidence: 1iiDiii] If a boost is used, it can be delivered either by
EBRT, generally with electrons, or by using an interstitial
radioactive implant.
The age of the patient should not be a determining factor in the selection of
breast-conserving treatment versus mastectomy. A study has shown that
treatment with lumpectomy and radiation therapy in women 65 years and
older produces survival and freedom-from-recurrence rates similar to those of
women younger than 65 years. Whether young women
with germ-line mutations or strong family histories are good candidates for
breast-conserving therapy is not certain. Retrospective studies indicate no difference in
local failure rates or overall survival (OS) when women with strong family histories
are compared with similarly treated women without such histories.[Level of evidence: 3iiiDii] The group with a
positive family history, however, does appear more likely to develop contralateral breast
cancer within 5 years. This risk for contralateral tumors may be even
greater in women who are positive for BRCA1 and BRCA2 mutations.[Level of evidence: 3iiiDii] Because of the available evidence indicating no difference
in outcome, women with strong family histories should be considered candidates
for breast-conserving treatment. For women with germ-line mutations in BRCA1
and BRCA2, further study of breast-conserving treatment is needed.
Breast-conserving surgery alone without radiation therapy has been compared
with breast-conserving surgery followed by radiation therapy in six prospective
randomized trials (including the National Surgical Adjuvant Breast and Bowel Project's trial [NSABP-B-06] and the Cancer and Leukemia Group B's trial [CLB-9343]) . In two of these trials, all patients also received adjuvant tamoxifen. Every trial demonstrated a lower
in-breast recurrence rate with radiation therapy, and this effect was present in all patient subgroups. In some groups, for example, women with receptor-positive small tumors and those older than 70 years, the absolute reduction in the rate of recurrence was small (<5%). The limited impact of radiation therapy in this group of women was also reported in a confirmatory observational study looking at in-breast control rates using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. The impact of radiation therapy on local control was additionally clarified by showing that healthy women aged 70 to 79 years were most likely to benefit from radiation therapy (number needed to treat [NNT] to prevent one event = 21–22 patients) when compared to women aged 80 years or older or to those who have comorbidities (NNT = 61–125 patients). The administration of radiation therapy may be associated with short-term morbidity, inconvenience, and potential long-term complications.
The axillary lymph nodes should be staged to aid in determining prognosis and
therapy. Although most authorities agree that an axillary node dissection in
the presence of clinically negative nodes is a necessary staging procedure,
controversy exists as to the extent of the procedure because of long-term
morbidity (e.g., arm discomfort and swelling) associated with it. Data suggest that
the level of lymph node involvement (stage I vs. stage II vs. stage III) does not add
independent prognostic information to the total number of positive axillary
nodes. The standard evaluation usually involves only a level I
and II dissection, thereby removing a satisfactory number of nodes for
evaluation (i.e., 6–10 at a minimum), while reducing morbidity from the procedure.
Several groups have attempted to define a population of women in whom the
probability of nodal metastasis is low enough to preclude axillary node biopsy.
In these single-institution case series, the prevalence of positive nodes in
patients with T1a tumors ranged from 9% to 16%. In another series, the
incidence of axillary node relapse in patients with T1a tumors treated without
axillary node dissection was 2%.[Level of evidence: 3iiiA] Because the
axillary node status remains the most important predictor of outcome in breast
cancer patients, insufficient evidence is available to recommend that lymph node
staging can be omitted in most patients with invasive breast cancer.
To decrease the morbidity of axillary lymphadenectomy while
maintaining accurate staging, several investigators have studied lymphatic
mapping and sentinel lymph node (SLN) biopsy in women with invasive breast
cancer. The SLN is defined as the first node in the lymphatic basin
that receives primary lymphatic flow. Studies have shown that the injection of
technetium-labeled sulfur colloid, vital blue dye, or both around the tumor or
biopsy cavity, or in the subareolar area, and subsequent drainage of these
compounds to the axilla results in the identification of the SLN in 92% to 98%
of patients. These reports demonstrate a 97.5% to 100%
concordance between SLN biopsy and complete axillary lymph node
dissection. The results of a randomized trial of 532 patients with T1 carcinomas undergoing either SLN biopsy plus complete axillary dissection or SLN biopsy alone showed, after a median follow-up of 78 months, no difference in 5-year DFS (92.9% in the SLN biopsy without routine axillary dissection group vs. 88.9% in patients having axillary dissection irrespective of SLN findings, P = .1).[Level of evidence: 1iiDii]
The reported false-negative rates of SLN biopsy using axillary node dissection as the gold standard range from 0% to 15% with an average of 8.8%. The
success rate varies with the surgeon’s experience and with the primary tumor
characteristics. In general, studies have restricted the use of SLN biopsy to
women with T1 and T2 disease, without evidence of multifocal involvement or
clinically positive lymph nodes.
SLN biopsy alone is associated with less morbidity than axillary lymphadenectomy. In a randomized trial of 1,031 women that compared SLN biopsy followed by axillary dissection when the SLN was positive with axillary dissection in all patients, quality of life at 1 year (as assessed by the frequency of patients experiencing a clinically significant deterioration in the Trial Outcome Index of the Functional Assessment of Cancer Therapy-Breast scale) was superior in the SLN biopsy group (23% vs. 35% deteriorating in the SLN biopsy vs. axillary dissection groups, respectively; P = .001).[Level of evidence 1iiC] Arm function was also better in the SLN group. NSABP-B32, a randomized study of 5,611 women, found the same results with respect to accuracy and technical success. Ongoing randomized trials will help to determine if both procedures yield comparable survival rates and if a therapeutic benefit comes from complete axillary lymphadenectomy in patients with SLN metastases. Although there are no data on its impact on survival, the SLN biopsy with complete dissection after a positive result is a commonly used alternative to axillary lymph node dissection. Prospective trials will be available soon to address the question of survival.
Breast reconstruction
For patients who opt for a total mastectomy, reconstructive surgery may be
used at the time of the mastectomy (immediate reconstruction)
or at some subsequent time (delayed reconstruction). Breast contour can
be restored by the submuscular insertion of an artificial implant
(saline-filled) or a rectus muscle or other flap. If a saline implant is used,
a tissue expander can be inserted beneath the pectoral muscle. Saline is
injected into the expander to stretch the tissues for a period of weeks or
months until the desired volume is obtained. The tissue expander is then
replaced by a permanent implant. (Visit the FDA's Web site for more
information on breast implants.) Rectus muscle flaps require a
considerably more complicated and prolonged operative procedure, and blood
transfusions may be required.
Following breast reconstruction, radiation
therapy can be delivered to the chest wall and regional nodes either in the
adjuvant setting or if local disease recurs. Radiation therapy following
reconstruction with a breast prosthesis may affect cosmesis, and the incidence
of capsular fibrosis, pain, or the need for implant removal may be
increased.
Adjuvant Radiation Therapy
Radiation therapy is regularly employed after breast-conservation surgery. Radiation therapy also can be indicated for postmastectomy patients. The main goal of adjuvant radiation therapy is to eradicate residual disease thus reducing local recurrence.
Post-breast conservation surgery
For women who are treated with breast-conserving surgery, the most common site of local recurrence is the conserved breast itself. The risk of recurrence in the conserved breast is substantial (>20%) even in confirmed axillary lymph node-negative women. Thus, whole breast radiation therapy after breast conserving surgery is recommended.
Although all trials assessing the role of radiation therapy in breast-conserving therapy have shown highly statistically significant reductions in local recurrence rate, no single trial has demonstrated a statistically significant reduction in mortality. However, in the 2005 Early Breast Cancer Trialists' Collaborative Group's (EBCTCG) update, when all relevant trials were combined, 15-year breast cancer mortality was reduced from 35.9% to 30.5% in women receiving radiation therapy (absolute difference of 5.4%; 95% CI, 2.1%–8.7%; breast cancer death rate ratio 0.83; 95% CI, 0.75–0.91; P = .002). There was a similar effect on all-cause mortality.
Although adjuvant whole-breast radiation is standard treatment, no trials have
addressed the role of regional lymph node radiation therapy in this setting. The National Cancer Institute of Canada's study (CAN-NCIC-MA20) has closed, but until results are reported, decisions regarding the use of such therapy must
rely on extrapolations from the postmastectomy setting and on knowledge of the
local-regional recurrence rates following conservation therapy with axillary
lymph node dissection for a given lesion.
Postmastectomy
Postoperative chest wall and regional lymph node adjuvant radiation therapy has traditionally been given
to selected patients considered at high risk for local-regional failure
following mastectomy. Radiation therapy can decrease local-regional recurrence
in this group, even among those patients who receive adjuvant chemotherapy.
Patients at highest risk for local recurrence include those with four or more
positive axillary nodes, grossly evident extracapsular nodal extension, large
primary tumors, and very close or positive deep margins of resection of the
primary tumor.
Patients with one to three involved nodes without any of the previously noted risk factors are at low risk of local recurrence, and the value of routine use of adjuvant radiation therapy in this setting has been unclear. The 2005 EBCTCG update indicates, however, that radiation therapy is beneficial, regardless of the number of lymph nodes involved.[Level of evidence: 1iiA] For women with node-positive disease postmastectomy and axillary clearance, radiation therapy reduced the 5-year local recurrence risk from 23% to 6% (absolute gain = 17%; 95% CI, 15.2%–18.8%). This translated into a significant (P = .002) reduction in breast cancer mortality, 54.7% versus 60.1% with an absolute gain of 5.4% (95% CI, 2.9%–7.9%). In subgroup analyses, the 5-year local recurrence rate was reduced by 12% (95% CI, 8.0%–16%) for women with one to three involved lymph nodes and by 14% (95% CI, 10%–18%) for women with four or more involved lymph nodes. In contrast, for women with node-negative disease, the absolute reduction in 5-year local recurrence was only 4% (P = .002; 95% CI, 1.8%–6.2%), and there was not a statistically significant reduction in 15-year breast cancer mortality in these patients (absolute gain = 1.0%; P > .1 95%; CI, -0.8%–2.8%). Further, an analysis of NSABP trials showed that even in patients with large (>5 cm) primary tumors, when axillary nodes were negative, the risk of isolated loco-regional recurrence was low enough (7.1%) that routine loco-regional radiation therapy was not warranted.
Adjuvant radiation therapy late toxic effects
Late toxic effects of radiation therapy, though uncommon, can include
radiation pneumonitis, cardiac events, arm edema, brachial plexopathy, and the
risk of second malignancies. Such toxic effects can be minimized with current
radiation delivery techniques and with careful delineation of the target
volume.
In a retrospective analysis of 1,624 women treated with conservative surgery and
adjuvant breast radiation at a single institution, the overall incidence of
symptomatic radiation pneumonitis was 1.0% at a median follow-up of 77 months.
The incidence of pneumonitis increased to 3.0% with the use of a supraclavicular
radiation field and to 8.8% when concurrent chemotherapy was administered.
The incidence was only 1.3% in patients who received sequential
chemotherapy.[Level of evidence: 3iii]
Controversy existed as to whether adjuvant radiation therapy to the left chest wall or breast, with or without inclusion of the regional lymphatics, had an association with increased cardiac mortality. In women treated with radiation therapy before 1980, an increased cardiac death rate was noted after 10 to 15 years, compared with women with nonradiated or right-side-only radiated breast cancer. This was probably caused by the radiation received by the left myocardium.
Modern radiation therapy techniques introduced in the 1990s minimized deep radiation to the underlying myocardium when left-sided chest wall or left breast radiation was used. Cardiac mortality decreased accordingly. At this time, cardiac mortality was also decreasing in the United States.
An analysis of SEER data from 1973 to 1989 reviewing deaths caused by ischemic heart disease in women who received breast or chest wall radiation showed that since 1980, no increased death rate due to ischemic heart disease in women who received left chest wall or breast radiation was found.[Level of evidence: 3iB]
Lymphedema consequent to cancer management remains a major quality-of-life
concern for breast cancer patients. Single-modality treatment of the axilla
(surgery or radiation) is associated with a low incidence of arm edema.
Axillary radiation therapy can increase the risk of arm edema in patients who
received axillary dissection from 2% to 10% with dissection alone to 13% to 18% with
adjuvant radiation therapy. (Refer to the PDQ summary on Lymphedema for more information.)
Radiation injury to the brachial plexus following adjuvant nodal radiation therapy is
a rare clinical entity for breast cancer patients. In a single-institution
study using current radiation techniques, 449 breast cancer patients treated
with postoperative radiation therapy to the breast and regional lymphatics were
followed for 5.5 years to assess the rate of brachial plexus injury. The
diagnosis of such injury was made clinically with computerized tomography to
distinguish radiation injury from tumor recurrence. When 54 Gy in 30 fractions
was delivered to the regional nodes, the incidence of symptomatic brachial
plexus injury was 1.0% compared with 5.9% when increased fraction sizes (45 Gy
in 15 fractions) were used.
The rate of second malignancies following adjuvant radiation therapy is very
low. Sarcomas in the treated field are rare, with the long-term risk at 0.2%
at 10 years. One report suggests an increase in contralateral breast
cancer for women younger than 45 years who have received chest wall
radiation therapy after mastectomy. No increased risk of contralateral
breast cancer occurs for women 45 years and older who receive radiation
therapy. Techniques to minimize the radiation dose to the contralateral
breast should be used to keep the absolute risk as low as possible. In
nonsmokers, the risk of lung cancer as a result of radiation exposure during
treatment is minimal when current dosimetry techniques are used. Smokers,
however, may have a small increased risk of lung cancer in the ipsilateral
lung.
Adjuvant Systemic Therapy
Hormone therapy
If ER status is used to select adjuvant treatment, the study should be
performed in a well-established, skilled laboratory. Immunohistochemical
assays appear to be at least as reliable as standard ligand-binding assays in
predicting response to adjuvant endocrine therapy.
Tamoxifen
The EBCTCG performed a meta-analysis of systemic treatment of early breast
cancer by hormone, cytotoxic, or biologic therapy methods in randomized trials
involving 144,939 women with stage I or stage II breast cancer. The most recent
analysis, which included information on 80,273 women in 71 trials of adjuvant
tamoxifen, was published in 2005. In this analysis, the benefit of
tamoxifen was found to be restricted to women with ER-positive or ER-unknown
breast tumors. In these women, the 15-year absolute reductions in
recurrence and mortality associated with 5 years of use were 12% and 9%,
respectively.[Level of evidence: 1iiA]
Allocation to approximately 5 years of adjuvant tamoxifen reduces the annual breast cancer death rate by 31%, largely irrespective of the use of chemotherapy and of age (<50 years, 50 to 69 years, ≥70 years), progesterone receptor status, or other tumor characteristics. This EBCTCG meta-analysis also confirmed the benefit of adjuvant
tamoxifen in ER-positive premenopausal women. Women younger than 50 years obtained a degree of benefit from 5 years of tamoxifen similar to that
obtained by older women. In addition, the proportional reductions in both
recurrence and mortality associated with tamoxifen use were similar in women
with either node-negative or node-positive breast cancer, but the absolute
improvement in survival at 10 years was greater in the latter group (5.3%
vs. 12.5% with 5 years of use).[Level of evidence: 1iiA]
Similar results were found in the International Breast Cancer Study Group-1393 trial. Of 1,246 women with stage II disease, only the women with ER-positive disease benefited from tamoxifen.
The optimal duration of tamoxifen use has been addressed by the EBCTCG
meta-analysis and by several large randomized trials. Results from the EBCTCG
meta-analysis show a highly significant advantage of 5 years versus 1 to 2 years of tamoxifen with respect to the risk of recurrence (proportionate reduction 15.2%; P < .001) and a less significant advantage with respect to mortality (proportionate reduction 7.9%; P = .01).
Results from the NSABP-B14 study, which compared 5 years of adjuvant tamoxifen to 10 years of
adjuvant tamoxifen for women with early-stage breast cancer, indicate no
advantage for continuation of tamoxifen beyond 5 years in women with
node-negative, ER-positive breast cancer.[Level of evidence: 1iA] Another
trial that included both node-positive and node-negative women also
demonstrated the equivalence of 5 years and 10 years of therapy.[Level of evidence: 1iiDii] In both trials, there was a trend toward a worse outcome
associated with a longer duration of treatment. In one trial, node-positive
women who had already received 5 years of tamoxifen following chemotherapy were
randomly assigned to continue therapy or observation. In the ER-positive
subgroup, a longer time-to-relapse was associated with continued
tamoxifen use, but no improvement in OS was observed. The current
recommendation is that adjuvant tamoxifen be discontinued after 5 years in all
patients as current standard therapy.
Clinical trials, such as the Adjuvant Tamoxifen Longer Against Shorter (ATLAS) trial and the Adjuvant Tamoxifen Treatment--Offer More? (CRC-TU-ATTOM
) trial are addressing different durations of adjuvant tamoxifen, and results are pending.
(Refer to the Letrozole section in the Aromatase inhibitors section of this summary for more information.)
Tamoxifen and chemotherapy
That chemotherapy should add to the effect of tamoxifen
in postmenopausal women has been postulated. In a trial (NSABP-B16) of node-positive women older than 50
years with hormone receptor–positive tumors, 3-year DFS and
OS rates were better in those who received doxorubicin,
cyclophosphamide, and tamoxifen versus tamoxifen alone (DFS was 84% vs. 67%; P = .004; OS was 93% vs. 85%;
P = .04).[Level of evidence: 1iiA] The NSABP-B20 study compared tamoxifen
alone with tamoxifen plus chemotherapy (cyclophosphamide, methotrexate, and fluorouracil [5-FU] [CMF] or sequential methotrexate and 5-FU)
in women with node-negative, ER-positive breast cancer. After 12 years of
follow-up, the chemotherapy plus tamoxifen regimen resulted in 89% DFS and 87% OS compared with an 79% DFS and
83% OS with tamoxifen alone.[Level of evidence: 1iiA] In
another study of postmenopausal women with node-positive disease, tamoxifen
alone was compared with tamoxifen plus three different schedules of CMF. A
small, DFS advantage was conferred by the addition of early CMF to
tamoxifen in women with ER-positive disease.[Level of evidence: 1iiDii]
However, another study in a similar patient population, in which women were
randomized to receive adjuvant tamoxifen with or without CMF, showed no benefit
in the chemotherapy arm; in this study, intravenous (day 1 every 3 weeks)
rather than oral cyclophosphamide was used.[Level of evidence: 1iiA] The
overall results of the available evidence suggest that the addition of
chemotherapy to tamoxifen in postmenopausal women with ER-positive disease
results in a significant, but small, survival advantage.
Tamoxifen toxic effects
The use of adjuvant tamoxifen has been associated with certain toxic effects.
The most important effect is the development of endometrial cancer which, in large
clinical trials, has been reported to occur at a rate that is two times to seven times
greater than that observed in untreated women. Women taking tamoxifen
should be evaluated
by a gynecologist if they experience any abnormal uterine bleeding. Although one
retrospective study raised concern that endometrial cancers in women taking
tamoxifen (40 mg/day) had a worse outcome and were characterized by higher-grade lesions and a more advanced stage than endometrial cancers in women not
treated with tamoxifen, other larger studies using standard tamoxifen doses (20
mg/day) have not supported this finding. Similar to estrogen,
tamoxifen produces endometrial hyperplasia, which can be a premalignant change.
In a cohort of women without a history of breast cancer who were randomly assigned to receive
tamoxifen or placebo on the British Pilot Breast Cancer Prevention Trial, 16%
of those on tamoxifen developed atypical hyperplasia at varying times from the
start of treatment (range, 3–75 months; median, 24 months), while no cases
occurred on the control arm. The value of endometrial biopsy,
hysteroscopy, and transvaginal ultrasound as screening tools is unclear.
Of concern is an increased risk of gastrointestinal
malignancy after tamoxifen therapy, but these findings are tentative, and
further study is needed.
Tamoxifen use is also associated with an increased incidence of deep venous
thrombosis and pulmonary emboli. In several adjuvant studies, the incidence
ranged from 1% to 2%. Clotting factor changes have been
observed in controlled studies of prolonged tamoxifen use at standard doses;
antithrombin III, fibrinogen, and platelet counts have been reported to be
minimally reduced in patients receiving tamoxifen. The relationship of
these changes to thromboembolic phenomena is not clear. Tamoxifen use may also be
associated with an increased risk of strokes. In the NSABP Breast
Cancer Prevention Trial (NSABP-P1), this increase was not statistically significant.
Another potential problem is the development of benign ovarian cysts,
which occurred in about 10% of women in a single study. The relationship between
tamoxifen and ovarian tumors requires further study. Short-term toxic
effects of tamoxifen use may include vasomotor symptoms and gynecologic symptoms
(e.g., vaginal discharge or irritation). (Refer to the PDQ summary on Sexuality and Reproductive Issues for more information.) Opthalmologic toxic effects have also been reported in patients receiving
tamoxifen; patients who complain of visual problems should be assessed
carefully. Because the teratogenic potential of tamoxifen is unknown,
contraception should be discussed with patients who are premenopausal or of
childbearing age and are candidates for treatment with this drug.
Tamoxifen therapy may also be associated with certain beneficial estrogenic
effects, including decreased total and low-density lipoprotein levels.
A large controlled Swedish trial has shown a decreased incidence of cardiac
disease in postmenopausal women taking tamoxifen. Results were better for
women taking tamoxifen for 5 years than for women taking it for 2 years.
In another trial, the risk of fatal myocardial infarction was significantly
decreased in patients receiving adjuvant tamoxifen for 5 years versus those
treated with surgery alone. In the NSABP-B14 study, the annual death
rate due to coronary heart disease was lower in the tamoxifen group than in the
placebo group (0.62 per 1,000 vs. 0.94 per 1,000), but this difference was not
statistically significant. To date, three large controlled trials have shown a decrease in heart disease.
Controlled studies have associated long-term tamoxifen use with preservation of
bone mineral density of the lumbar spine in postmenopausal women. In
premenopausal women, decreased bone mineral density is a possibility.
Ovarian ablation, tamoxifen, and chemotherapy
The EBCTCG meta-analysis included almost 8,000 premenopausal women who were randomly assigned to undergo ovarian ablation with surgery or radiation therapy (4,317) or ovarian suppression with luteinizing hormone-releasing hormone (LHRH) agonists (3,408). Overall, ovarian ablation or suppression reduced the absolute risk of recurrence at 15 years by 4.3% (P < .001) and the risk of death from breast cancer by 3.2% (P = .004). No evidence showed that the relative benefit of suppression differed from that of ablation, but the benefit of either was less in patients who received chemotherapy.[Level of evidence: 1iiA]
A single study of more
than 300 patients that compared cyclophosphamide, methotrexate, 5-FU, and
prednisone (CMFP) with the same chemotherapy regimen plus surgical oophorectomy
showed no additional survival benefit from oophorectomy.[Level of evidence: 1iiA] Three trials (including the International Breast Cancer Study Group's trial [IBCSG-VIII] and the Eastern Cooperative Oncology Group's trial [EST-5188]) involving more than 3,000 patients assessed the impact on DFS and OS from the use of an LHRH analogue (in one trial, 50% of the patients had radiation oophorectomy rather than an LHRH analogue) in addition to chemotherapy.[Level of evidence: 1iiA] None of the trials identified a statistically significant benefit in OS or DFS from ovarian suppression.
As an adjuvant strategy, ovarian ablation has also been compared
with chemotherapy in premenopausal women. In a direct comparison of surgical or
radiation ablation and CMF, DFS and OS rates were
identical in 332 premenopausal women with stage II disease.[Level of evidence: 1iiA] A trial of 599 premenopausal node-positive patients found leuprorelin acetate to be similar to CMF with respect to DFS and OS. A Danish trial compared ovarian ablation or suppression to CMF (nine cycles intravenously every 3 weeks) in premenopausal, ER-positive women and found no difference in OS or DFS in the two study groups. The study did not have tamoxifen as an adjuvant arm and also did not use taxanes or anthracyclines. Results may have been different with these two contemporary modifications to the study. A trial of CMF versus tamoxifen plus ovarian ablation (e.g., by surgery,
radiation therapy, or gonadotropin-releasing hormone [GnRH]) in premenopausal or perimenopausal women with
receptor-positive tumors has been reported.[Level of evidence: 1iiA] In
this small trial, which did not meet its target accrual, the combination of
tamoxifen and ovarian ablation provided comparable DFS and OS rates.
In three larger trials in which medical ovarian ablation with goserelin was used, the impact of goserelin alone on DFS was found to be comparable to CMF in the subgroup of ER+ patients,[Level of evidence: 2Dii] whereas the combination of goserelin and tamoxifen was associated with prolonged DFS compared with CMF alone.[Level of evidence: 1iiDii] Whether tamoxifen or aromatase inhibitors add to ovarian ablation, and the elucidation of the optimal roles for endocrine manipulation and chemotherapy in receptor-positive premenopausal women, require further evaluation. These issues are the subject of several trials.
Aromatase inhibitors
Based on disease-free survival advantage as described below, aromatase inhibitors have become the first-line adjuvant therapy for postmenopausal women; however, because there is no demonstrated survival advantage to aromatase inhibitors, tamoxifen remains a reasonable alternative.
Anastrozole
A large randomized trial of 9,366 patients has compared the use of the aromatase inhibitor anastrozole and the combination of anastrozole and tamoxifen with tamoxifen alone as adjuvant therapy for postmenopausal patients with node-negative and node-positive disease. Most (84%) of the patients in the study were hormone-receptor positive. Slightly more than 20% had received chemotherapy. With a median follow-up of 33.3 months, no benefit was observed for the combination arm relative to tamoxifen. Patients on anastrozole, however, had a significantly longer DFS (hazard ratio [HR] = 0.83) than those on tamoxifen. In an analysis conducted when all but 8% of the patients had completed protocol therapy at a follow-up of 68 months, the benefit of anastrozole relative to tamoxifen with respect to DFS was slightly less (HR = 0.87; 95% CI, 0.78–0.96; P = .01). A greater benefit was seen in hormone receptor-positive patients (HR = 0.83; 95% CI, .73–0.94; P = .05). There was an improvement in time to recurrence (HR = 0.79; 95% CI, 0.70–0.90; P = .005), distant DFS (HR = 0.86; 95% CI, 0.74–0.99; P = .04) and contralateral breast cancer (42% reduction; P = .01) in patients who received anastrozole.[Level of evidence: 1iDii] No difference was shown in OS (HR = 0.97; 95% CI, 0.85–1.12; P = .7 ). Arthralgia and fractures were reported significantly more often in patients who received anastrozole, whereas hot flushes, vaginal bleeding and discharge, endometrial cancer, ischemic cerebrovascular events, venous thromboembolic and deep venous thromboembolic events were more common in patients who received tamoxifen. An American Society of Clinical Oncology (ASCO) Technology Assessment panel has commented on the implications of these results.
Three trials examined the effect of switching to anastrozole to complete a total of 5 years of therapy after 2 to 3 years of tamoxifen. One study, which included 448 patients, demonstrated a statistically significant reduction in DFS (HR = 0.35; 95% CI, 0.18–0.68; P = .001) but no difference in OS.[Level of evidence: 1iiA] The other two trials (including the Austrian Breast and Colorectal Cancer Study Group's trial [ ABCSG-8]) were reported together. A total of 3,224 patients were randomized after 2 years of tamoxifen to continue tamoxifen for a total of 5 years or to take anastrozole for 3 years. After a median follow-up of 78 months, an improvement in all-cause mortality (HR = 0.61; 95% CI, 0.42–0.88; P = .007) was observed.
A meta-analysis of these three studies showed that patients who switched to anastrozole had significant improvements in DFS (HR = 0.59; 95% CI, 0.48–0.74; P < .001), EFS (HR = 0.55; 95% CI, 0.42–0.71; P < .001), distant DFS (HR = 0.61; 95% CI, 0.45–0.83; P= .002), and OS (HR = 0.71; 95% CI, 0.52–0.98; P = .04) compared with the patients who remained on tamoxifen.
Letrozole
A large double-blinded randomized trial of 8,010 postmenopausal women with hormone receptor-positive breast cancer compared the use of letrozole versus tamoxifen given continuously for 5 years or with crossover to the alternate drug at 2 years. In an updated analysis from the Breast International Group (BIG-1-98) including only the 4,922 women who received tamoxifen or letrozole for 5 years, at a median follow-up time of 51 months, DFS was significantly superior in patients treated with letrozole (HR = 0.82; 95% CI, 0.71–0.95; P = .007; 5-year DFS = 84.0% vs. 81.1%).[Level of evidence: 1iDii] OS was not significantly different (HR = 0.91; 95% CI, 0.75–1.11; P = .35). Patients on letrozole had significantly fewer thromboembolic events, endometrial pathology, hot flashes, night sweating, and less vaginal bleeding. Patients on tamoxifen had significantly fewer bone fractures, arthralgia, hypercholesterolemia, and cardiac events other than ischemic heart disease and cardiac failures.
A large double-blinded randomized trial (CAN-NCIC-MA17) of 5,187 patients compared the use of letrozole versus placebo in receptor-positive postmenopausal women who had received tamoxifen for approximately 5 (4.5–6.0) years. After the first planned interim analysis, when median follow-up for patients on study was 2.4 years, the results were unblinded because of a highly significant (P < .008) difference in DFS (HR = 0.57) favoring the letrozole arm.[Level of evidence: 1iDii] After 3 years of follow-up, 4.8% of the women on the letrozole arm had developed recurrent disease or new primaries versus 9.8% on the placebo arm (95% CI for the difference, 2.7%–7.3%). Women on letrozole had significantly more hot flashes, arthritis, arthralgia and myalgia, but less vaginal bleeding. New diagnoses of osteoporosis were more frequent on letrozole (5.8% vs. 4.5%), though the difference was not statistically significant (P = .07). Because of the early unblinding of the study, longer-term comparative data on the risks and benefits of letrozole in this setting will not be available. An updated analysis including all events prior to unblinding confirmed the results of the interim analysis. In addition, a statistically significant improvement in distant DFS was found for patients on letrozole (HR = 0.60; 95% CI, 0.43–0.84; P = .002). Although no significant difference was found in the total study population, the node-positive patients on letrozole also experienced a statistically significant improvement in OS (HR = 0.61; 95% CI, 0.38–0.98; P = .04), though the P value was not corrected for multiple comparisons. An ASCO Technology Assessment panel has commented on the implications of these results.
Exemestane
A large double-blinded randomized trial (BIG-9702) of 4,742 patients compared continuing tamoxifen with switching to exemestane for a total of 5 years of therapy in women who had received 2 to 3 years of tamoxifen. After the second planned interim analysis, when median follow-up for patients on the study was 30.6 months, the results were released because of a highly significant (P < .005) difference in DFS (HR = 0.68) favoring the exemestane arm.[Level of evidence: 1iDii] After a median follow-up of 55.7 months, the HR for DFS was 0.76 (95% CI, 0.66–0.88; P = .001) in favor of exemestane. At 2.5 years after randomization, 3.3% fewer patients on exemestane had developed a DFS event (95% CI, 1.6–4.9). The HR for OS was 0.85 (95% CI, 0.7–1.02; P = .08).[Level of evidence: 1iA] Women on exemestane had significantly more arthralgia, diarrhea, hypertension, fractures, arthritis, musculoskeletal pain, carpal tunnel syndrome, insomnia, and osteoporosis, but women on tamoxifen had significantly more gynecologic symptoms, muscle cramps, vaginal bleeding and discharge, thromboembolic disease, endometrial hyperplasia, and uterine polyps. (For information on diarrhea, refer to the PDQ summary on Gastrointestinal Complications; for information on insomnia, refer to the PDQ summary on Sleep Disorders.)
Chemotherapy
Overview of chemotherapy
Some of the most important data on the benefit of adjuvant chemotherapy came from the EBCTCG, which meets every 5 years to review data from global breast cancer trials. The year 2000 overview analysis (published in 2005) summarized the results of randomized adjuvant trials initiated by 1995. The analyses of adjuvant chemotherapy involved 28,764 women participating in 60 trials of combination chemotherapy (polychemotherapy) versus no chemotherapy, 14,470 women in 17 trials of anthracycline-containing versus CMF-type chemotherapy, and 6,125 women in 11 trials of longer versus shorter chemotherapy duration.
For women younger than 50 years, polychemotherapy reduced the annual risk of disease relapse and death from breast cancer by 37% and 30%, respectively. This translated into a 10% absolute improvement in 15-year survival (HR = 42% vs. 32%).
For women aged 50 to 69 years, the annual risk of relapse or death from breast cancer was decreased by 19% and 12%, respectively. This translated into a 3% absolute gain in 15-year survival (HR = 50% vs. 47%).
The absolute gain in survival for polychemotherapy versus no adjuvant therapy in women younger than 50 was twice as great at 15 years as it was at 5 years (10% vs. 4.7%), while the main effect on disease recurrence was seen in the first 5 years. The 15-year cumulative reduction in mortality from 6 months of an anthracycline-based regimen (e.g., fluorouracil, doxorubicin, cyclophosphamide [FAC] or fluorouracil, epirubicin, cyclophosphamide [FEC]) was 38% in women younger than 50 years, and 20% in those aged 50 to 60 years.
The meta-analysis also showed that the reduction in risk of
recurrence was similar in the presence or absence of tamoxifen, irrespective of
age (<50 years vs. 50 to 69 years), though the result did not attain statistical
significance in those randomly assigned women younger than 50 years. This
finding, however, is most likely due to the relatively small number of younger women in trials
of combined chemoendocrine therapy. Few women older than 70 years had been studied, and specific conclusions could not be reached in this group.
Importantly, these data were derived from clinical trials in which patients were not selected for adjuvant therapy according to ER status, and they were initiated before the advent of taxane-containing, dose-dense, or trastuzumab-based therapy. As a result, they may not reflect treatment outcomes based on evolving treatment patterns.
Results of individual trials are generally in agreement with the conclusions of
the meta-analysis. The NSABP-B13 study demonstrated a benefit for
chemotherapy with sequential methotrexate and 5-FU versus surgery alone in
patients with node-negative, ER-negative tumors.[Level of evidence: 1iiA]
Duration of CMF-based chemotherapy
The EBCTCG meta-analysis assessed data from five trials comparing durations of at
least 6 months with longer durations of 9 to 24 months. No survival benefit was
demonstrated for durations greater than 6 months.[Level of evidence: 1iiA]
Anthracycline-based versus CMF-based regimens
The EBCTCG meta-analysis analyzed 11 trials that began in 1976 through 1989 in
which women were randomized to receive regimens containing anthracyclines (e.g., doxorubicin or epirubicin) versus CMF alone. The EBCTCG overview analysis directly compared anthracycline-containing regimens (mostly 6 months of FEC or FAC) with CMF (either oral or IV) in approximately 14,000 women, 64% of whom were under 50 years. Compared to CMF, anthracycline-based regimens were associated with a modest but statistically significant 11% proportional reduction in the annual risk of disease recurrence, and a 16% reduction in the annual risk of death. In each case, the absolute difference in outcomes between anthracycline-based and CMF-type chemotherapy was about 3% at 5 years and 4% at 10 years.[Level of evidence: 1iiA]
The largest direct comparison of
cyclophosphamide, doxorubicin, and 5-fluorouracil (CAF) (six cycles) versus CMF (six cycles) occurred in a U.S. Intergroup study (INT-0102), which was not included in the meta-analysis. In this study, 2,691 patients were
randomized to receive CAF or CMF with a second randomization to 5 years of
tamoxifen versus no tamoxifen. Ten-year follow-up estimates indicated that CAF was not significantly better than CMF (P = .13) for the primary outcome of DFS (77% vs. 75%; HR = 1.09; 95% CI, 0.94–1.27). CAF had slightly better OS than CMF (85% vs. 82%, HR = 1.19 for CMF vs. CAF; 95% CI, 0.99–1.43), though values were statistically significant in the planned one-sided test (P = .03). Toxicity was greater with CAF and did not increase with tamoxifen. Overall, tamoxifen had no benefit (DFS, P = .16; OS, P = .37), but the tamoxifen effect differed by high-risk groups. For high-risk node-positive patients, tamoxifen was beneficial (DFS, hazard ratio [HR] = 1.32 for no tamoxifen vs. tamoxifen; 95% CI, 1.09–1.61; P = .003; OS, HR = 1.26; 95% CI, 0.99–1.61; P = .03) but not for high-risk node-negative patients (DFS, HR = 0.81 for no tamoxifen vs. tamoxifen; 95% CI, 0.64–1.03; OS, HR = 0.79; 95% CI, 0.60–1.05). The conclusion of this trial was that CAF did not improve DFS compared with CMF; and, there was a slight effect on OS. Given greater toxicity, CAF cannot be concluded to be superior to CMF. Tamoxifen is effective in high-risk node-positive disease but not in high-risk node-negative disease.[Level of evidence: 1iiA]
Several investigators have attempted to improve outcomes by combining CMF and
anthracycline-containing regimens. Two Italian studies have evaluated these
regimens. In one study, 490 premenopausal and postmenopausal women with one to three axillary
lymph nodes were randomized to receive CMF (12 cycles) or CMF (eight cycles)
followed by doxorubicin (four cycles). After a median observation of 17.5 years, no statistically significant difference was documented in the first study (relapse-free survival [RFS], HR = 1.06; total survival, HR = 1.03). In contrast, the delivery of doxorubicin first, followed by CMF significantly reduced the risk of disease relapse (HR = 0.68; 95% CI, 0.54–0.87; P =.0017) and death (HR = 0.74; 95% CI, 0.57–0.95; P = .018) compared with the alternating regimen. In the other study, 403 premenopausal and postmenopausal
women with four or more positive axillary lymph nodes were randomized to receive
doxorubicin (four cycles) followed by CMF (eight cycles) or CMF (two cycles) alternating
with doxorubicin (one cycle) for a total of 12 cycles. Women who received
doxorubicin followed by CMF had better RFS (42% vs. 28%; P = .002)
and OS (58% vs. 44%; P = .002).[Level of evidence: 1iiA]
The NSABP-B15 trial randomized 2,194 patients with axillary node-positive breast cancer
and tumors determined nonresponsive to tamoxifen to doxorubicin and cyclophosphamide (AC) (four cycles), CMF (six cycles), or AC (four cycles) followed after a
6-month delay by CMF (three cycles). No differences were seen in DFS or
OS among the three groups.[Level of evidence: 1iiA] This study
has also shown no difference in survival rates between four cycles of AC and six
cycles of CMF.
The results of these various studies comparing and combining CMF and
anthracycline-containing regimens suggest a slight advantage for the
anthracycline regimens in both premenopausal and postmenopausal patients. Uncertainty remains, however, about whether there is an advantage to combining both regimens.
Evidence suggests that particular tumor characteristics may
predict anthracycline-responsiveness. Data from retrospective analyses of
randomized clinical trials suggest that, in patients with node-positive breast
cancer, the benefit from standard-dose versus lower-dose adjuvant CAF, or the
addition of doxorubicin to the adjuvant regimen, is restricted to those
patients whose tumors overexpress HER2/neu.[Level of evidence: 1iiA] A retrospective analysis of the HER2/neu status of 710 premenopausal, node-positive women was undertaken to see the effects of adjuvant chemotherapy with CMF or cyclophosphamide, epirubicin, and fluorouracil (CEF).[Level of evidence: 2A] HER2/neu was measured using fluorescence in situ hybridization, polymerase chain reaction, and immunohistochemical methods. The study confirmed previous data indicating that the amplification of HER2/neu was associated with a decrease in RFS and OS. In patients with HER2/neu amplification, the RFS and OS was increased by CEF. In the absence of HER2/neu amplification, CEF and CMF were similiar to RFS (HR for relapse = 0.91; 95% CI, 0.71–1.18; P = .049) and OS (HR for death = 1.06; 95% CI, 0.83–1.44; P = .68). Similar results were seen in a meta-analysis that included 5,354 patients in whom HER2 status was known from eight randomized trials (including the one just described) comparing anthracycline-containing regimens with non–anthracycline-containing regimens.
The role of adding taxanes to adjuvant therapy
A number of trials have addressed the benefit of adding a taxane (paclitaxel or docetaxel) to an anthracycline-based adjuvant chemotherapy regimen. A literature-based meta-analysis of 13 such studies demonstrated that the inclusion of a taxane improved both DFS and OS (DFS: HR = 0.83; 95% CI, 0.79–0.87; P < .0001; OS: HR = 0.85; 95% CI, 0.79–0.91; P < .0001).[Level of evidence: 1iiA] Five-year absolute survival differences were 5% for DFS and 3% for OS in favor of taxane-containing regimens. There were no differences in benefit observed in patient subsets defined by nodal status, hormone receptor status, or age/menopausal status. There was also no apparent difference in efficacy between the two agents. However, none of the studies reviewed involved a direct comparison between paclitaxel and docetaxel.
A European Cooperative Oncology Group–led intergroup trial (E-1199) involving 4,950 patients compared, in a factorial design, two schedules (weekly and every 3 weeks) of the two drugs (docetaxel vs. paclitaxel) following standard-dose AC chemotherapy given every 3 weeks.[Level of evidence: 1iiA] There was no difference observed in the overall comparison with regard to DFS of docetaxel to paclitaxel (odds ratio [OR] 1.03; 95% CI, 0.91–1.16; P = .61) or between the 1-week and 3-week schedules (OR 1.06; 95% CI, 0.94–1.20; P = .33). However, there was a significant interaction between the drug administered and schedule for both DFS (0.003) and OS (0.01). Thus, compared with paclitaxel given every 3 weeks, paclitaxel given weekly improved both DFS (OR 1.27; 95% CI, 1.01–1.57; P = .006) and OS (OR 1.32; 95% CI, 1.02–1.72; P = .01). Docetaxel given every 3 weeks was also superior in DFS to paclitaxel given every 3 weeks (OR 1.23; 95% CI, 1.00–1.52; P = .02), but the difference was not statistically significant for OS (OR 1.13; 95% CI, 0.88–1.46; P = .25). Docetaxel given weekly was not superior to paclitaxel given every 3 weeks. There was no stated a priori basis for expecting that varying the schedule of administration would have opposite effects for the two drugs. Thus, these results are hypothesis generating and should be confirmed.
Dose-intensity, dose-density, and high-dose chemotherapy
Retrospective and some prospective data support the view that physicians should
avoid arbitrary reductions in dose intensity. The data for
the benefit of dose escalation in breast cancer, however, are more controversial. The CALGB-8541 trial compared three dose intensities of CAF in
1,550 patients with node-positive breast cancer. Patients received either CAF
(300/30/300 mg/m2 every 4 weeks for four cycles; low-dose arm), CAF
(400/40/400 mg/m2 every 4 weeks for six cycles; moderate-dose arm),
or CAF (600/60/600 mg/m2 every 4 weeks for four cycles; high-dose
arm). The high-dose arm had twice the dose intensity and twice the drug dose
as the low-dose arm. The moderate-dose arm had 66% of the dose intensity
as the high-dose arm but the same total drug dose. At a median follow-up of 9
years, DFS and OS on the high-dose and intermediate-dose
arms were superior to the corresponding survival measures on the low-dose arm
(P = .001) with no difference in these measures between the high-dose and
intermediate-dose arms.[Level of evidence: 1iiA] The higher dose levels used
in this trial are currently considered standard, so it is unclear whether this
trial is supportive of the value of dose intensity or, rather, supportive of
the concept of a threshold level below which treatment becomes ineffective.
Other trials have clearly escalated doses beyond the standard range. The NSABP-B22 and NSABP-B25 trials, for example, escalated the dose of cyclophosphamide to 1,200 mg/m2 (without granulocyte-colony stimulating factor [G-CSF]) and
2,400 mg/m2 (with G-CSF), respectively, with no
significant advantage observed in DFS or OS compared with
the standard dose of 600 mg/m2.[Level of evidence: 1iiA]
A U.S. Intergroup study (CLB-9344) randomly assigned women with node-positive tumors to three
dose levels of doxorubicin (60, 75, and 90 mg/m2). Following
treatment with doxorubicin, a second randomization occurred to paclitaxel or to
no further therapy. After chemotherapy, patients with ER-positive tumors were
offered a planned course of tamoxifen for 5 years. No difference in DFS related to the dose of doxorubicin was found. In contrast, a Canadian trial (CAN-NCIC-MA5) in
which cyclophosphamide, epirubicin, and 5-FU (CEF) were given to
a total dose of 720 mg/m2 for a period of six 4-week cycles
demonstrated at a median follow-up of 10 years for live patients, a 10-year RFS of 52% for patients who received CEF compared with 45% for CMF patients (HR for CMF vs. CEF = 1.31; stratified log-rank, P = .007). The 10-year OS for patients who received CEF and CMF are 62% and 58%, respectively (HR for CMF vs. CEF = 1.18; stratified log-rank, P = .085). The rates of acute leukemia have not changed since the original report, whereas the rates of congestive heart failure are slightly higher (four patients [1.1%] in the CEF group vs. one patient [0.3%] in the CMF group).[Level of evidence: 1iiA] The
design of the trial does not allow a determination of whether anthracycline or
dose-intensity or both is responsible for the improved outcome. A French trial
showed that higher doses of epirubicin led to a high survival rate in women
with poor-prognosis disease. A randomized trial that increased duration of epirubicin did not lead to increased survival at 10 years in node-positive premenopausal women.
A U.S. Intergroup trial (CLB-9741) compared, in a 2 × 2 factorial design, the use of adriamycin, cyclophosphamide, and paclitaxel concurrently (adriamycin and cyclophosphamide followed by paclitaxel) versus sequentially (adriamycin followed by paclitaxel followed by cyclophosphamide), given every 3 weeks or every 2 weeks with filgrastim, in 2,005 node-positive premenopausal and postmenopausal patients. At a median follow-up of 68 months, dose-dense treatment improved the primary end point, DFS in all patient population (HR = 0.80; P =.018) but not OS (HR = 0.85; P =.12). There was no interaction between density and sequence. Severe neutropenia was less frequent in patients who received the dose-dense regimens. Grade 2 anemia (hemoglobin <10g/dL) was more frequent in the adriamycin and cyclophosphamide followed by paclitaxel every 2 weeks' arm (P < .001). At cycle five, this same arm had the lowest nadir hemoglobin of 10.7 g/dL, 0.9 g/dL lower than the other arms. Also, epoetin alpha use was highest in this arm compared with the three other arms (P = .013). In conclusion, dose-dense adriamycin and cyclophosphamide followed by paclitaxel every 14 days in C2 was associated with a greater incidence of moderate anemia, higher use of epoetin alpha, and more red cell transfusions than the other arms.[Level of evidence: 1iiA]
Several clinical trials (including EST- 2190) have tested high-dose chemotherapy with bone marrow
transplant (BMT) or stem cell support in women with more than ten positive lymph
nodes and in women with four to nine positive lymph nodes. A prospective randomized trial of 403 patients testing the use of two tandem high-dose chemotherapy courses demonstrated a statistically significant (P = .02) difference in 5-year survival (75% vs. 70%) with a 49-month median follow-up.[Level of evidence: 1iiA] The remaining trials comparing
conventional chemotherapy to high-dose chemotherapy with BMT or stem cell
support in high-risk patients in the adjuvant setting indicated no OS or
EFS benefit from the high-dose chemotherapy with BMT or stem
cell support.[Level of evidence: 1iiA] The information to date does not support the use of high-dose
chemotherapy outside the context of a randomized clinical trial.
Also, a systemic review of nine randomized controlled trials comparing the effectiveness of high-dose chemotherapy and autograft with conventional chemotherapy for women with early poor prognosis breast cancer was performed. In total 1,758 women were randomly assigned to receive high-dose chemotherapy with autograft, and 1,767 women were randomly assigned to receive conventional chemotherapy. There were 48 noncancer-related deaths on the high dose arm and four on the conventional dose arm (RR = 7.74; 95% CI, 3.43–17.50). There was no statistically significant difference in OS between women who received high-dose chemotherapy with autograft and women who received conventional chemotherapy, either at 3 years (RR = 1.02; 95% CI, 0.98–1.06), or at 5 years (RR = 0.98, 95% CI, 0.93–1.05). There was a statistically significant benefit in EFS at 3 years for the group who received high dose chemotherapy (RR = 1.11; 95% CI, 1.05–1.18). However, this
significance was lost at 5 years (RR = 1.00; 95% CI, 0.92–1.08).
Other chemotherapy regimens
The NSABP-B19 trial compared CMF to sequential methotrexate followed by 5-FU in
1,095 women with node-negative, ER-negative tumors. After 13 years of follow-up, an overall benefit was seen for CMF relative to methotrexate plus 5-FU (MF) (RFS: HR = 0.59, 95% CI, 0.45–0.77, P < .001; OS: HR = 0.71; 95% CI, 0.55–0.92; P = .01). All age and menopausal groups demonstrated an RFS benefit, and most demonstrated an OS benefit.[Level of evidence: 1iiA] Serious toxicity (≥grade 3), especially febrile
neutropenia, was more frequent among CMF-treated patients. With no outcome
advantage in older women and more toxic effects from the CMF regimen, the
results of this study suggested that methotrexate followed by 5-FU was a
reasonable substitute for CMF for older women.
A U.S. Intergroup study (CLB-9344) randomly assigned women with node-positive tumors to three
dose levels of doxorubicin (60, 75, and 90 mg/m2) and a fixed
dose of cyclophosphamide (600 mg/m2) every 3 weeks for four cycles.
After AC chemotherapy, patients underwent a second randomization to paclitaxel
(175 mg/m2) every 3 weeks for four cycles, and women with
ER-positive tumors also received tamoxifen for 5 years. Although the
dose-escalation of doxorubicin was not beneficial, the addition of paclitaxel
resulted in statistically significant improvements in DFS (5%) and
OS (3%).[Level of evidence: 1iiA] The results of a second trial, the NSABP-B28 trial, have also been reported.
This trial randomized 3,060 women with node-positive breast cancer to four
cycles of postoperative AC or four cycles of AC followed by four cycles of
paclitaxel. All women older than 50 years, and those younger than 50 years with receptor-positive disease, received tamoxifen. In this trial,
DFS was significantly improved by the addition of paclitaxel (hazard ratio [HR] = 0.83; 95% CI, 0.72–0.96; P = .006; 5-year DFS = 76% vs. 72%). The difference in OS was small (HR = 0.93), however, and not statistically significant (P = .46).[Level of evidence: 1iiA]
The regimen of 5-FU, adriamycin, and cyclophosphamide (FAC) compared with docetaxel plus doxorubicin and cyclophosphamide (TAC) has been studied in 1,491 women with node-positive disease in the Breast Cancer International Research Group's (BCIRG-001) trial. Six cycles of either regimen were given as adjuvant postoperative therapy. A 75% DFS rate existed at 5 years in the TAC group compared with a 68% survival in the FAC group (P = .001). TAC was associated with a 30% overall lower risk of death (5% absolute difference) than FAC (HR = .70; 98% CI, 0.53–0.91; P < .008). Anemia, neutropenia, febrile neutropenia, and infections were more common in the TAC group. No deaths were associated with infections in either group.[Level of evidence: 1iiA] (For information on anemia, refer to the PDQ summary on Fatigue.)
Monoclonal antibodies
Five clinical trials addressing the role of the anti-HER2/neu antibody, trastuzumab, as adjuvant therapy for patients with HER2-overexpressing cancers have released the results of interim analyses.
In the HERceptin Adjuvant (HERA) (BIG-01-01) trial, which is the largest study (5,090 patients), trastuzumab was given every 3 weeks within 7 weeks of the completion of primary therapy that included an anthracycline-containing chemotherapy regimen given preoperatively or postoperatively plus or minus locoregional radiation therapy. Although the results of the comparison 1 year versus 2 years of trastuzumab have not been released yet, there are available data for 3,387 patients (1,694 in the 1-year trastuzumab arm and 1,693 in the observation arm). Of these patients, the median age was 49 years, about 33% had node-negative disease, and nearly 50% had hormone receptor (ER and PR)-negative disease. Patients who were treated with 1-year of trastuzumab experienced a 46% lower risk of a first event (hazard ratio [HR] = 0.54; 95% CI, 0.43–0.67; P < .001), corresponding to an absolute DFS benefit of 8.4% at 2 years (95% CI, 2.1–14.8). The updated results at 23.5 months' follow-up showed an unadjusted HR for the risk of death with trastuzumab compared with observation of 0.66 (95%CI, 0.47–0.91; P = .0115), corresponding to an absolute OS benefit of 2.7%. There were 218 DFS events reported with trastuzumab compared with 321 DFS events reported with observation. The unadjusted HR for the risk of an event with trastuzumab was 0.64 (0.54–0.76; P < .001), corresponding to an absolute DFS benefit of 6.3%.
In the combined analysis of the NSABP-B31 and Intergroup N9831 trials, trastuzumab was given weekly, concurrently, or immediately after the paclitaxel component of the AC with paclitaxel regimen. The results were confirmed in a joint analysis of the two studies, with a combined enrollment of 3,676 patients, that demonstrated a highly significant improvement in DFS (HR = 0.48; P < .001; 3-year DFS = 87% vs. 75%), as well as a significant improvement in OS (HR = 0.67; P = .015; 3-year OS = 94.3% vs. 91.7%; 4-year OS = 91.4% vs. 86.6%). Patients treated with trastuzumab experienced a longer DFS with a 52% lower risk of a DFS event (HR = 0.48; 95% CI, 0.39–0.59; P < .001), corresponding to an absolute difference in DFS of 11.8% at 3 years and 18% at 4 years. The risk of distant recurrence was 53% lower (HR = 0.47; 95%CI, 0.37–0.61; P < .001) in patients treated with trastuzumab, and the risk of death was 33% lower (HR = 0.67; 95%CI, 0.48–0.93; P = .015) in these patients.
The BCIRG-006study is a three-arm large trial containing two anthracycline arms [AC-D: doxorubicin, cyclophosphamide, docetaxel or AC-DH: doxorubicin, cyclophosphamide, docetaxel, and trastuzumab] and a nonanthracycline one [DCbH: docetaxel, carboplatin, trastuzumab]. In its second interim efficacy analysis with a median follow-up of 36 months, there were 462 DFS events and 185 deaths. For DFS, the HR was 0.61 for patients in the AC-DH arm (95%CI, 0.48–0.76; P < .001) and 0.67 for patients in the DCbH arm (95%CI, 0.54–0.83; P=.003), compared with the AC-D. This translated to absolute benefits (from years 2 to 4) of 6% and 5%, respectively with the addition of trastuzumab. Nevertheless, longer follow-up is needed in patients in the DCbH arm to warrant the omission of anthracyclines in these patients.
The Finland Herceptin (FINHER) study assessed the impact of a much shorter course of trastuzumab. In this trial, 232 women younger than 67 years with node-positive or high-risk (>2 cm tumor size) node-negative HER2-overexpressing breast cancer were given nine weekly infusions of trastuzumab concurrently with docetaxel or vinorelbine followed by FEC. At a 3-year median follow-up, the risk of recurrence and/or death was significantly reduced in patients receiving trastuzumab (HR = 0.41;P = .01; 95% CI, 0.21–0.83; 3 year DFS = 89% vs. 78%). The difference in OS (HR = 0.41) was not statistically significant (P = .07; 95% CI, 0.16–1.08).[Level of evidence: 1iiA]
Currently being investigated in the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization's trial (ALTTO) is the role of lapatinib (in combination with, in sequence to, in comparison to, or as an alternative to trastuzumab) in the adjuvant setting. Lapatinib is a small molecule tyrosine kinase inhibitor that is capable of dual-receptor inhibition of both EGFR and HER2 and seems to be less cardiotoxic than trastuzumab. In phase I/II studies as a single agent, lapatinib has resulted in objective responses between 4.3% and 7.8% in ER2-positive patients who had progressed on multiple trastuzumab-containing regimens with a substantial number having stable disease at 4 months (34%–41%) and 6 months (18%–21%). In a phase III trial (GSK-EGF100151), lapatinib plus capecitabine was superior to capecitabine alone in women with HER2-positive advanced breast cancer that has progressed after treatment with regimens that included an anthracycline, a taxane, and trastuzumab.
The hazard ratio for time to progression was 0.49 (95% CI, 0.34–0.71; P < .001), with 49 events in the combination-therapy group and 72 events in the monotherapy group. The median time to progression was 8.4 months in the combination-therapy group as compared with 4.4 months in the monotherapy group.
Cardiotoxicity with adjuvant trastuzumab
In the HERA (BIG-01-01) trial, severe congestive heart failure (CHF NYHA class III–IV) occurred in 0.6% of patients treated with trastuzumab. Symptomatic CHF occurred in 1.7% and 0.06% of patients in the trastuzumab and observation arms, respectively. Fifty-one patients experienced a confirmed left ventricular ejection fraction (LVEF) decrease (defined as an EF decrease of >10 points from baseline to an LVEF <50%) with trastuzumab, which recovered or stabilized within 3 to 6 weeks of initial treatment in 86% of cases. In the NSABP-B31 trial, 31 of 850 patients in the trastuzumab arm had confirmed symptomatic cardiac events, compared with 5 of 814 patients in the control arm. The 3-year cumulative incidence of cardiac events for trastuzumab-treated patients was 4.1%, compared with 0.8% of patients in the control arm (95% CI, 1.7%–4.9%). Asymptomatic decline in LVEF (defined by >10% decline or to 55%) occurred in 17% of patients in the trastuzumab arm (95% CI, 15%–20%) and 34% of patients in the control arm (95%CI, 31%–38%), with a HR = 2.1 (95%CI, 1.7–2.6; P < .001). In the N9831 trial, 39 cardiac events were reported in the three arms over a 3-year period. The 3-year cumulative incidence of cardiac events in arm A was 0.35% (no trastuzumab), arm B, 3.5% (trastuzumab following paclitaxel) and arm C, 2.5% (trastuzumab concomitant with paclitaxel).
In the BCIRG-006 trial, clinically symptomatic cardiac events were detected in 0.38% of patients in the AC-D arm, 1.87% of patients in the AC-DH arm, and 0.37% of patients in the DCbH arm. There was also a statistically significant higher incidence of asymptomatic and persistent decrease in LVEF in the AC-DH arm than with either the AC-D or DCbH arms. No cardiac deaths were reported in the BCIRG 006 trial.
In the FINHER trial, none of the patients who received trastuzumab experienced clinically significant cardiac events. In fact, LVEF was preserved in all of the women receiving trastuzumab, but the number of patients receiving adjuvant trastuzumab was very low.
Treatment options for HER2-positive early breast cancer:
- Standard treatment is 1 year of adjuvant trastuzumab therapy. Results of the 1 year versus 2 years of trastuzumab of the HERA trial are awaited, as are the results of the Protocol of
Herceptin Adjuvant with Reduced
Exposure (PHARE) trial , which compares 1 year versus 6 months of adjuvant trastuzumab.
Timing of Primary and Adjuvant Therapy
Postoperative adjuvant chemotherapy
The optimal time to initiate adjuvant therapy is uncertain. A single study that addressed the use of perioperative adjuvant chemotherapy in node-positive
patients showed no advantage in DFS when a single cycle of
perioperative chemotherapy was given in addition to standard therapy initiated
4 weeks after surgery. A single cycle of immediate postoperative
chemotherapy alone was inferior.
Preoperative adjuvant chemotherapy
A randomized clinical trial (NSABP-B18) has been performed to evaluate
preoperative chemotherapy in the management of patients with stage I or stage
II breast cancer. After preoperative therapy with four cycles of doxorubicin and
cyclophosphamide, 80% of the assessable patients had a reduction in tumor size
of at least 50%, and 36% of the patients had a complete clinical response. More patients
treated with preoperative chemotherapy were able to have breast-conservation
procedures as compared with those patients in the postoperative chemotherapy
group (68% vs. 60%). Twenty-seven percent of the women in the preoperative
therapy group for whom a mastectomy had been planned prior to being randomly assigned
underwent a lumpectomy. No statistically significant
difference existed, however, in DFS, distant DFS, or OS in the
patients receiving preoperative chemotherapy as compared with those receiving
postoperative chemotherapy.[Level of evidence: 1iiA]
An EORTC randomized trial (EORTC-10902)
likewise demonstrated no improvement in DFS or
OS, but showed an increased frequency of conservative surgery with the
use of preoperative versus postoperative FEC chemotherapy.[Level of evidence: 1iiA] Preoperative
chemotherapy may be beneficial in women who desire breast conservation surgery
but who would otherwise not be considered candidates because of the size of their
tumor. In a meta-analysis including all trials that compared the use of the same chemotherapy preoperatively and postoperatively, the use of preoperative chemotherapy was associated with a higher rate of local recurrence. Although preoperative chemotherapy affects the results of SLN biopsy,
one small study indicated that SLN biopsy technique was feasible in this
setting. Before SLN biopsy can replace complete axillary lymphadenectomy,
randomized trials are needed to confirm that both procedures yield comparable
survival rates.
Adjuvant radiation and chemotherapy
The optimal sequence of adjuvant chemotherapy and radiation therapy after
breast-conserving surgery was studied in a randomized trial. Patients
received either chemotherapy first (n = 122), consisting of CMFP plus doxorubicin
repeated every 21 days for four cycles, followed by breast radiation, or breast
radiation first (n = 122), followed by the same chemotherapy. With a median
follow-up of 5 years, OS was 73% for the radiation-first group
and 81% for the chemotherapy-first group (P = .11).[Level of evidence: 1iiA]
The 5-year crude rates of first recurrence by site in the radiation-first and
chemotherapy-first groups, respectively, were 5% and 14% for local recurrence
and 32% and 20% for distant or regional recurrence or both. This difference in
the pattern of recurrence was of borderline statistical significance (P = .07).
Further analyses revealed that differences in recurrence patterns persisted for
most subgroups with the exception of those that had either negative tumor
margins or one to three positive lymph nodes. For these two subgroups, sequence
assignment made little difference in local or distant recurrence rates,
though the statistical power of these subgroup analyses was low. Potential
explanations for the increase in distant recurrence noted in the radiation
therapy-first group are that chemotherapy was delayed for a median of 17 weeks
after surgery, and that this group received lower chemotherapy dosages due to
increased myelosuppression.
Two additional randomized trials, though not specifically designed to address
the timing of radiation therapy and adjuvant chemotherapy, do add useful
information. In the NSABP-B15 trial, patients undergoing
breast-conserving surgery received either one course of CMF (n = 194) followed by
radiation therapy followed by five additional cycles of CMF, or they received four
cycles of AC (n = 199) followed by radiation therapy. No differences in
DFS, distant DFS, and OS were
observed between these two arms.[Level of evidence: 1iiA] The International
Breast Cancer Study Group trials VI and VII also varied the timing of
radiation therapy with CMF adjuvant chemotherapy. These studies showed
that delays from 2 to 7 months in radiation therapy after surgery had no effect
on the rate of local recurrence.
Based on the above studies, delaying radiation therapy for several months after
breast-conserving surgery until the completion of adjuvant chemotherapy appears
safe and may be preferable for patients at high risk of distant dissemination.
Timing of surgery
Several retrospective reviews have indicated that statistically significantly better
DFS is achieved for premenopausal women with breast cancer
and positive axillary lymph nodes if breast surgery is performed during the
luteal phase (days 15–36) as compared with the follicular phase (days 0–14) of
the menstrual cycle.[Level of evidence: 1iiA] Several other
studies, however, have failed to support this finding or have found opposite
results.[Level of evidence: 1iiA] Because of the inconsistent
findings of these studies, it would be premature to mandate a modification in
the scheduling of breast cancer operations according to the patient’s menstrual
cycle. A prospectively controlled trial (UCLA-9810046) has been completed but is not yet analyzed.
Chemotherapy risks
Adjuvant chemotherapy is associated with several well-characterized toxic
effects that vary according to the individual drugs used in each regimen.
Common toxic effects include nausea and vomiting, myelosuppression, alopecia,
and mucositis. Less common, but serious, toxic effects include heart failure
(if an anthracycline is used), thromboembolic events, and premature
menopause.
(Refer to the PDQ summary on Nausea and Vomiting; for information on mucositis, refer to the PDQ summary on Oral Complications of Chemotherapy and Head/Neck Radiation; and for information on symptoms associated with premature menopause, refer to the PDQ summary on Fever, Sweats, and Hot Flashes.)
Cognitive impairment has been reported to occur after the administration of some chemotherapy regimens. However, data on this topic from prospective randomized studies are lacking. (Refer to the PDQ summary on Cognitive Disorders and Delirium for more information.)
The EBCTCG meta-analysis revealed that women who received adjuvant combination
chemotherapy did have a 20% (standard deviation = 10) reduction in the annual
odds of developing contralateral breast cancer. This small proportional
reduction translated into an absolute benefit that was only marginally
statistically significant, but it indicates that chemotherapy does not increase
the risk of contralateral disease. In addition, the analysis showed no
statistically significant increase in deaths attributed to other cancers or to
vascular causes among all women randomly assigned to receive chemotherapy. The use of anthracycline-containing regimens, however—particularly those containing an increased dose of cyclophosphamide—has been associated with a cumulative risk of developing acute leukemia of 0.2% to 1.7% at 5 years. This risk increases to more than 4% in patients receiving high cumulative doses of both epirubicin (>720 mg/m2) and cyclophosphamide (>6,300 mg/m2).
Chemotherapy and tamoxifen risks
Adjuvant combinations of tamoxifen and chemotherapy administered concurrently
to enhance efficacy may also have enhanced toxic effects. A single study
randomly assigned postmenopausal women with node-positive, ER-positive tumors
to receive tamoxifen (30 mg/day for 2 years) plus CMF (intravenously for 6
months) (n = 353) or tamoxifen alone (n = 352). Of the women receiving
combined chemohormonal therapy, 13.6% developed one or more thromboembolic events
compared with 2.6% in the tamoxifen-alone group (P < .001). Also,
statistically significantly more women were on combined treatment who developed
severe thromboembolic events (grade 3–5), most of which (39 of 54) occurred
while the women were actually receiving chemotherapy. Not all studies
that compared concurrent chemotherapy plus tamoxifen with tamoxifen alone, however, have
reported such high rates. In the NSABP-B16 study that compared
tamoxifen (20 mg/day for 5 years) plus chemotherapy with doxorubicin plus
cyclophosphamide (four cycles) with tamoxifen alone, 4.9% of the women on combined
treatment had thromboembolic events versus 2.1% of women on tamoxifen
alone. Whether tamoxifen should be given concurrently or after the completion of chemotherapy has been addressed in an Intergroup trial (INT-0100), published in abstract form only, that compared the concurrent and sequential administration of CAF and tamoxifen in postmenopausal hormone receptor-positive patients. Sequential administration resulted in superior DFS that was significant at 8 years (67% vs. 62%; P = .045).[Level of evidence: 1iiDii]
Candidates for whom adjuvant therapy may not be necessary include individuals with small primary tumors (<1 cm) and negative axillary nodes who have
an excellent prognosis, with nearly 90% of patients alive and free of disease
at 20 years in one series. A U.S. Intergroup study (INT-0102) observed patients off
treatment with tumors of low-risk (tumors too small for biochemical ER/PR
assay) and uncertain-risk (tumors <2 cm, ER-positive and PR-positive, and low S-phase
fractions). This low-risk and uncertain-risk subset had a 96% 5-year survival
rate without adjuvant therapy. Whether this group of patients would
derive long-term benefit from tamoxifen for either its adjuvant or preventive
effects remains uncertain. Clearly, this group has a risk of developing a new
breast cancer that would meet the eligibility criteria that were used in the
Breast Cancer Prevention Trial that demonstrated a benefit with tamoxifen.
Proposals have been made to treat elderly patients with tamoxifen alone and without
surgery. This approach has unacceptably high local failure rates and, outside
of a clinical trial setting, should be used only for patients who are not
candidates for mastectomy or breast-conserving surgery plus radiation therapy,
or for those who refuse these options.
Treatment Options
Primary therapy
Local-regional treatment:
- Breast-conserving therapy (lumpectomy, breast radiation, and surgical
staging of the axilla).
- Modified radical mastectomy (removal of the entire breast with level I–II
axillary dissection) with or without breast reconstruction.
- SLN biopsy is under clinical evaluation by the American College of Surgeons Oncology Group's trial (ACOSOG-Z0010).
Adjuvant radiation therapy postmastectomy in axillary node-positive tumors:
- For one to three nodes: unclear role for regional radiation (infra/supraclavicular
nodes, internal mammary nodes, axillary nodes, and chest wall).
- For more than four nodes or extranodal involvement: regional radiation is
advised.
Adjuvant systemic therapy:
An International Consensus Panel proposed a three-tiered risk classification for
patients with negative axillary lymph nodes. This classification, with
some modification, is described below:
Table 1: Risk Categories for Women With Node-Negative Breast Cancer
|
|
Low risk (has all listed factors)
|
Intermediate risk (risk classified between the other two categories)
|
High risk (has at least one listed factor)
|
|
Tumor size
|
≤1 cm
|
1–2 cm
|
>2 cm
|
|
ER or PR Status
|
positive
|
positive
|
negative
|
|
Tumor grade
|
grade 1
|
grade 1–2
|
grade 2–3
|
The original Consensus Panel classification also required that women be 35
years or older to be included in the low-risk group and included women
35 years and younger in the high-risk group, based admittedly on
indirect evidence. Traditionally, certain uncommon histologies (e.g., tubular,
medullary, and mucinous) have also been associated with favorable prognosis and
may be considered as low-risk factors. Some additional tumor characteristics
that may eventually prove helpful in the prognosis of node-negative disease
include the tumor proliferative fraction (S-phase) and the level of HER2/neu
expression.
Regardless of how one chooses to characterize node-negative tumors, evidence
from clinical trials suggests that various types of adjuvant therapies benefit certain subgroups of patients with these kinds of tumors. The same is true for
women with node-positive breast cancer. What has become clear after reviewing
results from multiple breast cancer treatment trials is that hormone therapy
and chemotherapy regimens generally offer the same proportional benefit to
women irrespective of their axillary lymph node status. The selection of
therapy is most appropriately based upon knowledge of an individual’s
risk of tumor recurrence balanced against the short-term and long-term risks of
adjuvant treatment. This approach should allow clinicians to help individuals
to determine if the gains anticipated from treatment are reasonable for
their particular situation. The treatment options presented below should be
modified based upon both patient and tumor characteristics.
Table 2: Adjuvant Systemic Treatment Options for Women With Axillary
Node-Negative Breast Cancer
|
Patient group
|
Low risk
|
Intermediate risk
|
High risk
|
|
Premenopausal, ER-positive or PR-positive
|
None or tamoxifen
|
Tamoxifen plus chemotherapy, tamoxifen alone, ovarian ablation, GnRH analog*
|
Chemotherapy plus tamoxifen, chemotherapy plus ablation or GnRH analog*, chemotherapy plus tamoxifen plus ovarian ablation or GnRH*, or ovarian ablation alone or with tamoxifen or GnRH alone or with tamoxifen
|
|
Premenopausal, ER-negative or PR-negative
|
—
|
—
|
Chemotherapy
|
|
Postmenopausal, ER-positive or PR-positive
|
None or tamoxifen
|
Tamoxifen plus chemotherapy, tamoxifen alone
|
Tamoxifen plus chemotherapy, tamoxifen alone
|
|
Postmenopausal, ER-negative or PR-negative
|
—
|
—
|
Chemotherapy
|
|
Older than 70 years
|
None or tamoxifen
|
Tamoxifen alone, tamoxifen plus chemotherapy
|
Tamoxifen; consider chemotherapy if ER-negative or PR-negative
|
Table 3: Treatment Options for Women With Axillary Node-Positive Breast
Cancer
|
Patient group
|
Treatments
|
|
Premenopausal, ER-positive or PR-positive
|
Chemotherapy plus tamoxifen, chemotherapy plus ovarian ablation/GnRH analog, chemotherapy plus tamoxifen plus ovarian ablation/GnRH analog*, ovarian ablation alone or with tamoxifen or GnRH alone or with tamoxifen
|
|
Premenopausal, ER-negative or PR-negative
|
Chemotherapy
|
|
Postmenopausal, ER-positive or PR-positive
|
Tamoxifen plus chemotherapy, tamoxifen alone
|
|
Postmenopausal, ER-negative or PR-negative
|
Chemotherapy
|
|
Older than 70 years
|
Tamoxifen alone; consider chemotherapy if receptor-negative
|
Current Clinical Trials
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with
stage I breast cancer, stage II breast cancer, stage IIIA breast cancer and stage IIIC breast cancer. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Stage IIIB, Inoperable IIIC, IV, Recurrent, and Metastatic Breast Cancer
Note: Some citations in the text of this section are followed by a level of
evidence. The PDQ editorial boards use a formal ranking system to help the
reader judge the strength of evidence linked to the reported results of a
therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more
information.)
Inoperable Stage IIIB or IIIC or Inflammatory Breast Cancer
Multimodality therapy delivered with curative intent is the standard of care
for patients with clinical stage IIIB disease. In a retrospective series, approximately 32% of patients with ipsilateral supraclavicular node involvement and no evidence of distant metastases (pN3c) had prolonged disease-free survival (DFS) at 10 years with combined modality therapy. Although these results have not been replicated in another series, this result suggests such patients should be treated with the same intent.
Initial surgery is generally
limited to biopsy to permit the determination of histology, estrogen-receptor (ER) and progesterone-receptor (PR) levels,
and human epidermal growth factor receptor 2 (HER2/neu) overexpression. Initial treatment with anthracycline-based
chemotherapy and/or taxane-based therapy is standard. In one series of
178 patients with inflammatory breast cancer, DFS was 28% at
15 years with a combined-modality approach.[Level of evidence: 3iiiDii] For
patients who respond to neoadjuvant chemotherapy, local therapy may consist of
total mastectomy with axillary lymph node dissection followed by postoperative
radiation therapy to the chest wall and regional lymphatics. Breast-conserving
therapy can be considered in patients with a good partial or complete response
to neoadjuvant chemotherapy. Subsequent systemic therapy may consist of
further chemotherapy. Hormone therapy should be administered to patients whose
tumors are ER-positive or unknown. All patients should be considered
candidates for clinical trials to evaluate the most appropriate fashion in
which to administer the various components of multimodality regimens.
Current Clinical Trials
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with
stage IIIB breast cancer, stage IIIC breast cancer and inflammatory breast cancer. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Stage IV, Recurrent, and Metastatic Breast Cancer
Recurrent breast cancer is often responsive to therapy, though treatment is
rarely curative at this stage of disease. Patients with localized
breast or chest wall recurrences, however, may be long-term survivors with appropriate
therapy. Prior to treatment for recurrent or metastatic cancer,
restaging to evaluate extent of disease is indicated. Cytologic or histologic
documentation of recurrent or metastatic disease should be obtained whenever
possible. The ER and PR levels,
HER2/neu positivity at the time of recurrence, and previous treatment should be
considered, if known, when selecting therapy. ER status may change at the time
of recurrence. In a single small study by the Cancer and Leukemia Group B (CALGB-8081), 36% of hormone receptor–positive
tumors were found to be receptor negative in biopsy specimens isolated at the
time of recurrence. Patients in this study had no interval treatment. If
ER and PR status is unknown, then the site(s) of recurrence, disease-free
interval, response to previous treatment, and menopausal status are useful in
selecting chemotherapy or hormone therapy.
Recurrent local-regional breast cancer
Patients with local-regional breast cancer recurrence may become long-term survivors
with appropriate therapy. A clinical trial indicated that between 10% and 20%
of patients will have locally recurrent disease in the breast between 1 and 9
years after breast-conservation surgery plus radiation therapy. Nine
percent to 25% of these patients will have distant metastases or locally
extensive disease at the time of recurrence. Patients with local-regional
recurrence should be considered for further local treatment (e.g., mastectomy).
In one series, the 5-year actuarial rate of relapse for patients treated for
invasive recurrence after initial breast conservation and radiation therapy was
52%. A phase III randomized study showed that local control of cutaneous metastases could be achieved with the application of topical miltefosine; however, the drug is not currently available in the United States.[Level of evidence: 1iiDiii]
Local chest wall recurrence following mastectomy is usually the harbinger of
widespread disease, but, in a subset of patients, it may be the only site of
recurrence. For patients in this subset, surgery and/or radiation therapy may
be curative. Patients with chest wall recurrences of less than 3
cm, axillary and internal mammary node recurrence (not
supraclavicular, which has a poorer survival), and a greater than 2-year
disease-free interval prior to recurrence have the best chance for prolonged
survival. The 5-year DFS rate in one series of such
patients was 25%, with a 10-year rate of 15%. The local-regional control
rate was 57% at 10 years. Systemic therapy should be considered in patients
with local regional recurrence caused by the high risk of subsequent metastases. No randomized controlled studies are available to guide patient care in this
situation.
Stage IV and metastatic disease
Systemic disease
Treatment for systemic disease is palliative in intent. Goals of treatment
include improving quality of life and prolongation of life. Although median
survival has been reported to be 18 to 24 months, some patients experience
long-term survival. Among patients treated with systemic chemotherapy at a
single institution between 1973 and 1982, 263 patients (16.6%) achieved
complete responses. Of those, 49 patients (3.1% of the total group) remained
in complete remission for more than 5 years, and 26 patients (1.5%) were still
in complete remission at 16 years.[Level of evidence: 3iiDiii]
Treatment of metastatic breast cancer will usually involve hormone therapy
and/or chemotherapy with or without trastuzumab. Radiation therapy
and/or surgery may be indicated for patients with limited symptomatic
metastases. All patients with metastatic or recurrent breast cancer should be
considered candidates for ongoing clinical trials.
Surgery
Surgery may be indicated for selected patients. Examples include patients who
need mastectomies for fungating/painful breast lesions, parenchymal brain or
vertebral metastases with spinal cord compression, isolated lung metastases,
pathologic (or impending) fractures, or pleural or pericardial effusions.
(Refer to the PDQ summary on Pain for more information; for information on pleural and pericardial effusions, refer to the PDQ summary on Cardiopulmonary Syndromes.)
Radiation therapy
Radiation therapy has a major role in the palliation of localized symptomatic
metastases. Indications include painful bony metastases, unresectable central
nervous system metastases (i.e., brain, meningeal, and spinal cord), bronchial
obstruction, and fungating/painful breast or chest wall lesions. Radiation
therapy should also be given following surgery for decompression of
intracranial or spinal cord metastases and following fixation of pathologic
fractures. Clinical trials (including the Radiation Therapy Oncology Group's trial [RTOG-9714]) are exploring the optimal radiation fractionation
schedule. Strontium 89, a systemically administered radionuclide, can be
administered for palliation of diffuse bony metastases.
(Refer to the PDQ summary on Pain for more information.)
Current Clinical Trials
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with
stage IV breast cancer and recurrent breast cancer. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Systemic Therapy
Bisphosphonates
The use of bisphosphonates to reduce skeletal morbidity in patients with bone
metastases should be considered. Results of randomized trials of
pamidronate and clodronate in patients with bony metastatic disease show
decreased skeletal morbidity.[Level of evidence: 1iC] Zoledronate has been at least as effective as pamidronate. (Refer to the PDQ summary on Pain for more information on bisphosphonates.)
Hormone therapy
Hormone therapy should generally be considered as initial treatment for a
postmenopausal patient with newly diagnosed metastatic disease if the patient’s
tumor is ER-positive, PR-positive, or ER/PR-unknown. Hormone therapy is
especially indicated if the patient’s disease involves only bone and soft
tissue and the patient has either not received adjuvant antiestrogen therapy or
has been off such therapy for more than 1 year. While tamoxifen has been used
in this setting for many years, several randomized trials suggest equivalent or superior response rates and progression-free survival for the aromatase inhibitors compared to tamoxifen.[Level of evidence: 1iiDiii] In a meta-analysis that included randomized trials in patients who were receiving an aromatase inhibitor as either their first or second hormonal therapy for metastatic disease, those who were randomized to a third-generation drug (anastrozole, letrozole, exemestane, or vorozole) lived longer (HR for death = 0.87; 95% CI, 0.82–0.93) than those who received standard therapy (tamoxifen or a progestational agent).[Level of evidence: 1iA]
Several randomized but underpowered trials have tried to determine if combined
hormone therapy (luteinizing hormone-releasing hormone [LHRH] agonists + tamoxifen) is superior to either approach
alone in premenopausal women. Results have been inconsistent. The best
study design compared buserelin (an LHRH agonist) versus tamoxifen versus the
combination in 161 premenopausal women with hormone receptor–positive
tumors. Patients receiving buserelin and tamoxifen had a significantly
improved median survival of 3.7 years compared with those receiving tamoxifen or
buserelin who survived 2.9 and 2.5 years, respectively (P = .01).[Level of evidence: 1iiA] Very few women in this trial received adjuvant tamoxifen,
which makes it difficult to assess whether these results are applicable to women
who relapse after adjuvant tamoxifen.
Women whose tumors are ER-positive or unknown, with bone or soft tissue
metastases only, who have received an antiestrogen within the past year should
be given second-line hormone therapy. Examples of second-line hormone therapy
in postmenopausal women include selective aromatase inhibitors, such as
anastrozole, letrozole, or exemestane; megestrol acetate; estrogens;
androgens; and the ER down-regulator, fulvestrant. In comparison to megestrol
acetate, all three currently available aromatase inhibitors have demonstrated, in
prospective randomized trials, at least equal efficacy and better
tolerability. In a meta-analysis that included randomized trials of patients who were receiving an aromatase inhibitor as either their first or second hormonal therapy for metastatic disease, those who were randomly assigned to a third-generation drug (e.g., anastrozole, letrozole, exemestane, or vorozole) lived longer (HR for death 0.87; 95% CI, 0.82–0.93) than those who received standard therapy (tamoxifen or a progestational agent).[Level of evidence: 1iA] Two randomized trials that enrolled 400 and 451
patients who had progressed after receiving tamoxifen demonstrated that
fulvestrant yielded similar results to anastrozole in terms of its impact on PFS. The proper sequence of these therapies is currently not known.
Premenopausal women should undergo oophorectomy (surgically, with external-beam
radiation therapy or with an LHRH agonist). Patients with lymphangitic
pulmonary metastases, major liver involvement, and/or central nervous system
involvement should not receive hormone therapy as a single modality. Patients
with structural compromise of weight-bearing bones should be considered for
surgical intervention and/or radiation in addition to systemic therapy.
Patients with vertebral body involvement should be evaluated for impending cord
compression even in the absence of neurologic symptoms. Increasing bone pain
and increasing alkaline phosphatase within the first several weeks of hormone
therapy does not necessarily imply disease progression. Patients with
extensive bony disease are at risk for the development of symptomatic
hypercalcemia early in the course of hormone therapy. Early failure (e.g.,
<6 months) on hormone therapy suggests that cytotoxic chemotherapy should be
the next modality employed.
Trastuzumab
Approximately 25% of patients with breast cancer have tumors that overexpress
HER2/neu. Trastuzumab is a humanized monoclonal antibody that
binds to the HER2/neu receptor. In patients previously treated with
cytotoxic chemotherapy whose tumors overexpress HER2/neu, administration of
trastuzumab as a single agent resulted in a response rate of 21%.[Level of evidence: 3iiiDiv] In a prospective trial, patients with metastatic disease
were randomized to receive either chemotherapy alone (doxorubicin and
cyclophosphamide or paclitaxel) or the same chemotherapy and trastuzumab.
Patients treated with chemotherapy plus trastuzumab had an overall survival
(OS) advantage as compared with those receiving chemotherapy alone (25.1 months vs.
20.3 months, P = .05).[Level of evidence: 1iiA] When combined with
doxorubicin, trastuzumab is associated with significant cardiac toxicity.
Consequently, patients with metastatic breast cancer with substantial
overexpression of HER2/neu are candidates for treatment with the combination of
trastuzumab and paclitaxel or for clinical studies of trastuzumab combined with
taxanes and other chemotherapeutic agents. In a randomized study of patients with metastatic breast cancer treated with trastuzumab, paclitaxel, and carboplatin, patients tolerated the combination well and had a longer time-to-progression with the addition of carboplatin to trastuzumab and paclitaxel.[Level of evidence: 1iDiii]
Lapatinib
Lapatinib is an orally administered tyrosine kinase inhibitor of both HER2/neu and the epidermal growth factor receptor. Lapatinib has shown activity in combination with capecitabine in patients who have HER2-positive metastatic breast cancer that progressed after treatment with trastuzumab. A nonblinded randomized trial (GSK-EGF100151) compared the combination of capecitabine and lapatinib in 324 patients with locally advanced or metastatic disease that progressed after therapies that included anthracyclines, taxanes, and trastuzumab. At the first planned interim analysis of the trial, a highly significant difference was found that favored the combination arm with respect to the primary study endpoint and time to progression (median time to progression 8.4 months vs. 4.4 months; HR = 0.49; 95% CI, 0.34–0.71; P < .001). There was no difference in overall survival (HR = 0.92; 95% CI, 0.58–1.46; P = .72).[Level of evidence: 1iiA] Patients on combination therapy were more likely to develop diarrhea, rash, and dyspepsia. No data on quality of life or treatment after progression are available. (For information on diarrhea, refer to the PDQ summary on Gastrointestinal Complications.)
Cytotoxic chemotherapy
Patients whose tumors have progressed on hormone therapy are candidates for
cytotoxic chemotherapy. Patients with hormone receptor–negative tumors and
those with visceral metastases are also candidates for cytotoxic agents.
Single agents that have shown activity in metastatic breast cancer:
- Anthracyclines.
- Doxorubicin.
- Epirubicin.
- Liposomal doxorubicin.
- Mitoxantrone.
- Taxanes.
- Paclitaxel.
- Docetaxel.
- Albumin-bound nanoparticle paclitaxel (ABI-007 or Abraxane).
- Alkylating agents.
- Cyclophosphamide.
- Fluoropyrimidines.
- Capecitabine.
- 5-FU.
- Antimetabolites.
- Methotrexate.
- Vinca alkaloids.
- Vinorelbine.
- Vinblastine.
- Vincristine.
- Platinum.
- Carboplatin.
- Cisplatin.
- Other.
- Gemcitabine.
- Mitomycin C.
Combination regimens that have shown activity in metastatic breast cancer:
- CA: cyclophosphamide and doxorubicin.
- Docetaxel and doxorubicin.
- CAF: cyclophosphamide, doxorubicin, 5-fluorouracil.
- CMF: cyclophosphamide, methotrexate, 5-fluorouracil.
- Doxorubicin and paclitaxel.
- Docetaxel and capecitabine.
- Vinorelbine and epirubicin.
- Capecitabine and ixabepilone.
Whether single-agent chemotherapy or combination chemotherapy
is preferable for first-line treatment is unclear. An Eastern Cooperative Oncology Intergroup study (E-1193) randomly assigned patients to receive paclitaxel and doxorubicin given both as a combination and sequentially. Although response rate and time-to-progression were both better for the combination, survival was the same in both groups.[Level of evidence: 1iiA] The rate of disease progression,
the presence or absence of comorbid medical conditions, and physician/patient
preference will influence the choice of therapy in individual patients. At
this time, no data support the superiority of any particular
regimen. Sequential use of single agents or combinations can be used for
patients who relapse. Combinations of chemotherapy and hormone therapy have
not shown an OS advantage over the sequential use of these
agents.
A systematic review of 17 randomized trials found that the addition of one or more chemotherapy drugs to a chemotherapy regimen in the attempt to intensify the treatment improved tumor response but had no effect on OS.[Level of evidence: 1iiA]
The optimal treatment duration for patients with responsive or stable disease
has been studied by several groups. For patients who attain a complete
response to initial therapy, two randomized trials have shown a prolonged
DFS from immediate treatment with a different chemotherapy
regimen compared to observation with treatment upon relapse.[Level of evidence: 1iiA] Neither of these
studies, however, showed an improvement in OS for patients who received
immediate treatment, and in one of these studies, survival was actually
worse in the immediately treated group. Similarly, no difference in survival
was noted when patients with partial response or stable disease after initial
therapy were randomized to receive either a different chemotherapy versus
observation or a different chemotherapy regimen given at higher versus
lower doses.[Level of evidence: 1iiA] These four studies indicate that
different combination regimens of additional chemotherapy immediately following
a patient’s best response to an induction chemotherapy regimen does not improve
OS. In view of the lack of a standard approach, patients
requiring second-line regimens are good candidates for clinical trials.
The potential for doxorubicin-induced cardiotoxicity should be considered in
the selection of chemotherapeutic regimens for an individual patient.
Recognized risk factors for cardiac toxicity include advanced age, prior
chest-wall radiation therapy, prior anthracycline exposure, hypertension, diabetes,
and known underlying heart disease. The cardioprotective drug dexrazoxane has
been shown to decrease the risk of doxorubicin-induced cardiac toxicity in
patients in controlled studies. The use of this agent has permitted patients
to receive greater cumulative doses of doxorubicin and allowed patients with
cardiac risk factors to receive doxorubicin. Dexrazoxane has a similar
protective effect in patients receiving epirubicin. The risks of cardiac
toxicity may also be reduced by administering doxorubicin as a continuous
intravenous infusion.
Studies comparing high-dose chemotherapy with stem cell support to conventional
chemotherapy in patients with metastatic disease indicate no
OS or relapse-free survival benefit for patients receiving high-dose
chemotherapy with stem cell support.[Level of evidence: 1iiA] In the
absence of data suggesting a benefit from high-dose chemotherapy with stem cell
support, this remains an area of clinical evaluation.
Current Clinical Trials
Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with
stage IIIB breast cancer, stage IIIC breast cancer, stage IV breast cancer, recurrent breast cancer and metastatic cancer. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Get More Information From NCI
Call 1-800-4-CANCER
For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 9:00 a.m. to 4:30 p.m. A trained Cancer Information Specialist is available to answer your questions.
Chat online
The NCI's LiveHelp® online chat service provides Internet users with the ability to chat online with an Information Specialist. The service is available from 9:00 a.m. to 11:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.
Write to us
For more information from the NCI, please write to this address:
- NCI Public Inquiries Office
- Suite 3036A
- 6116 Executive Boulevard, MSC8322
- Bethesda, MD 20892-8322
Search the NCI Web site
The NCI Web site provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use the search box in the upper right corner of each Web page. The results for a wide range of search terms will include a list of "Best Bets," editorially chosen Web pages that are most closely related to the search term entered.
There are also many other places to get materials and information about cancer treatment and services. Hospitals in your area may have information about local and regional agencies that have information on finances, getting to and from treatment, receiving care at home, and dealing with problems related to cancer treatment.
Find Publications
The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237).
Changes to This Summary (08/26/2009)
The PDQ cancer information summaries are reviewed regularly and updated as
new information becomes available. This section describes the latest
changes made to this summary as of the date above.
Editorial changes were made to this summary.
More Information
About PDQ
Additional PDQ Summaries
Important:
This information is intended mainly for use by doctors and other health care professionals. If you have questions about this topic, you can ask your doctor, or call the Cancer Information Service at 1-800-4-CANCER (1-800-422-6237).
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