Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically confirmed Stage I, IIA or IIB invasive
adenocarcinoma of the breast with T1-3, pN0 and M0 classification Must have undergone
total mastectomy or lumpectomy followed by an axillary dissection or sentinel node
resection if participating in NSABP B-32 Histologically negative axillary lymph nodes OR
Histologically negative sentinel lymph nodes if participating in NSABP B-32 Lumpectomy and
axillary dissection acceptable only if margins of resected specimen are histologically
free of invasive tumor or ductal carcinoma in situ and other dominant masses within the
ipsilateral breast remnant are histologically confirmed to be benign Additional operation
after resection is allowed in order to obtain clear margins No bilateral malignancy of the
breast ER positive tumors as defined by at least one of the following: At least 10 fmol/mg
cytosol protein by either dextran-coated charcoal or sucrose density gradient methods
Positive or not definitely negative results by the enzyme immunoassay method (EIA) or by
immunocytochemical assay No more than 63 days from time of initial cytologic or histologic
diagnosis of breast cancer till randomization No bone metastases (confirmation must be
made for those with skeletal pain) Tumor must be no greater than 5 cm in its greatest
dimension for patients who are treated by lumpectomy and axillary dissection Hormone
receptor status: Estrogen receptor positive

PATIENT CHARACTERISTICS: Age: Not specified Sex: Female Menopausal status: Not specified
Life expectancy: At least 10 years (excluding diagnosis of cancer) Performance status: Not
specified Hematopoietic: WBC at least 4,000/mm3 Platelet count postoperative at least
100,000/mm3 Hepatic: Bilirubin normal SGOT/SGPT normal Renal: Creatinine normal
Cardiovascular: No cardiac disease that would preclude the use of doxorubicin (for
patients who are to receive adjuvant chemotherapy in this study), including: Myocardial
infarction Angina pectoris that requires antianginal medication History of congestive
heart failure Arrhythmia associated with concurrent heart failure or cardiac dysfunction
Valvular disease with cardiac compromise Cardiomegaly or ventricular hypertrophy unless
left ventricular function is within normal limits Poorly controlled hypertension Other: No
prior invasive breast cancer or ductal carcimoma in situ No systemic disease that would
preclude patients from any part of study No history of symptomatic gallbladder or biliary
tract disease unless patient has undergone cholecystectomy No ulceration, erythema,
infiltration of the skin or underlying chest wall (complete fixation), peau d'orange, or
skin edema of any magnitude No prior nonbreast malignancies in past 10 years except:
Squamous or basal cell carcinoma of the skin that has been effectively treated Carcinoma
in situ of the cervix that has been treated by operation only Lobular carcinoma in situ of
the ipsilateral or contralateral breast treated by segmented resection only No psychiatric
or addictive disorders Not pregnant or nursing Negative pregnancy test

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior biologic therapy for breast cancer
Chemotherapy: No prior chemotherapy for breast cancer No prior anthracycline therapy for
patients who are to receive adjuvant chemotherapy in this study Endocrine therapy: No
prior endocrine therapy for breast cancer Must discontinue any sex hormonal therapy before
prior to and during study Radiotherapy: No prior radiotherapy for breast cancer No breast
radiation therapy before randomization for patients who receive lumpectomy Surgery: See
Disease Characteristics At least 2 weeks since last surgical procedure Other: No
concurrent cyclosporine therapy No concurrent heparin or warfarin anticoagulation therapy