DISEASE CHARACTERISTICS: Adenocarcinoma of the breast with 1 or more histologically proven positive axillary nodes OR Adenocarcinoma of the breast with negative axillary nodes or adverse prognostic factors such that the patient is at high risk for recurrence and node negative lesion is characterized by the following features: Tumor at least 1 cm Poorly differentiated, SBR grade III, or MSBR grade V and/or lymphatic/vascular invasion Pathologic review by experienced breast pathologist recommended if grade is unspecified and lymphatic/vascular invasion is absent Disease considered potentially curable and treated by 1 of the following: Complete surgical removal of the breast plus axillary node dissection Partial surgical removal of the breast plus axillary node dissection, with the intention of giving breast irradiation following completion of an adjuvant chemotherapy regimen Regional nodal or chest wall irradiation not prohibited but strongly discouraged No evidence of residual tumor in the axilla following dissection No microscopic evidence of residual tumor at the resection margins following total mastectomy Further excision highly recommended if there is microscopic residual disease present at partial mastectomy margins If further excision is not undertaken, a radiotherapy boost to the tumor bed is required in addition to breast irradiation given following protocol chemotherapy Disease clinically staged prior to surgery as T1-T3a, N0-2, M0 No clinical T4 disease, i.e.: No extension to the chest wall No edema (including peau d'orange) No skin ulceration No satellite skin nodules confined to the same breast No inflammatory carcinoma Disease pathologically staged following surgery as TNM stage I, II, or III (T0-4; N0-2; M0) T4 allowed only with dermal involvement on pathology assessment No evidence of metastatic disease beyond the homolateral axillary nodes on pre-chemotherapy chest x-ray, bone scan (with radiographs of suspicious areas), and abdominal ultrasound (required only if bilirubin, alkaline phosphatase, or AST/ALT are elevated) Simultaneous bilateral breast carcinoma allowed Complete tumor resection on both breasts required Axillary dissection on both sides must meet criteria as above if both sides are clinically node-positive Axillary dissection on the second side optional if the axilla is clinically negative at the time of surgery and the other side is node-positive Adjuvant chemotherapy must begin within 14 weeks of initial pathologic diagnosis Hormone receptor status: Any receptor level allowed (values must be available if biochemical method used; immunocytochemical assay permitted)