DISEASE CHARACTERISTICS: Histologically confirmed stage IIA, IIB, or III breast cancer treated with radical surgery (e.g., mastectomy, quadrantectomy, tumorectomy) and axillary lymph node dissection Positive axillary lymph nodes No more than 9 metastatic lymph nodes No distant metastases or local or locoregional disease No more than 5 weeks between surgery and beginning of study Hormone receptor status: Not specified