Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically confirmed adenocarcinoma of the breast Pathologic
stage T1-3, N1-2, M0 No clinical or pathologic T4 disease No primary tumor fixed to chest
wall No axillary nodes fixed to chest wall or neurovascular bundle No preoperative arm
edema No clinical skin involvement (microscopic focal dermal invasion or dermal lymphatic
involvement eligible) No clinical N2 disease Modified radical mastectomy or lumpectomy
required prior to entry Sentinel node biopsy allowed Randomization required within 12
weeks from definitive surgery Surgery dated from mastectomy or axillary dissection for
lumpectomy No positive deep mastectomy margins Radiotherapy planned within 12 weeks
following axillary node dissection for lumpectomy patients Synchronous bilateral breast
cancer eligible If tumor is at least 2 cm, then nodes not involved If no tumor is at least
2 cm, then at least 1 node must be involved Both invasive primaries receptor-positive
Previously treated, noninvasive breast cancer eligible No prior invasive breast cancer No
adenoid cystic, squamous, or sarcomatous histology Hormone receptor status: Estrogen- or
progesterone-receptor positive, i.e.: At least 10 fmole/mg cytosol protein by
ligand-binding assay OR Receptor positive by immunocytochemistry

PATIENT CHARACTERISTICS: Age: 65 and over OR Postmenopausal and ineligible/inappropriate
for or declined other active node positive adjuvant studies Sex: Female Menopausal status:
Postmenopausal, defined as: At least 1 year since last menstrual period Hysterectomized
with bilateral oophorectomy Hysterectomized with 1 or both ovaries remaining and either:
Over 60 FSH in postmenopausal range Not surgically castrated, under 60, and on HRT FSH
elevated 2 weeks after HRT discontinued Performance status: Not specified Life expectancy:
At least 7 years except for breast cancer Hematopoietic: WBC greater than 3,000/mm3
Platelet count at least 100,000/mm3 Hemoglobin at least 10 g/dL Hepatic: Bilirubin no
greater than 1.5 mg/dL AST less than 2 times normal Renal: Creatinine no greater than 2.0
mg/dL BUN no greater than 25.0 mg/dL Other: No extensive macular degeneration on exam
within 1 year of entry, e.g.: No exudative or atrophic macular lesions that reduce
corrected vision to less than 20/40 Health adequate for protocol treatment No nutritional
supplementation except single daily multivitamin No other vitamin A supplements
Gynecologic exam within the past year required of women who retain a uterus No second
malignancy within the past 10 years except: Inactive nonmelanomatous skin cancer Carcinoma
in situ of the cervix Prior noninvasive contralateral breast cancer

PRIOR CONCURRENT THERAPY: No prior chemotherapy or hormonal therapy for breast cancer
except: Up to 1 month of tamoxifen if started by a non participating physician At least 2
weeks since hormone replacement therapy No concurrent megestrol