Adjuvant endocrine therapy, cytotoxic chemotherapy and immunotherapy in stage II breast cancer: 6-year result

Six-year results of a prospective, randomized clinical trial of three treatment regimes [(1) cytoxan, methotrexate and 5-fluorouracil (CMF); (2) CMF plus the antiestrogen drug, tamoxifen (CMFT); (3) CMFT plus Bacillus Calmette-Guerin (BCG) vaccinations] in 312 women with stage II breast cancer are reported. Addition of tamoxifen to CMF therapy significantly decreased the number of recurrences at 6 years in ER + patients with ≥ 4 positive axillary lymph nodes, and in those with tumor diameter in excess of 3cm. The beneficial effect of tamoxifen appeared to be independent of the menopausal status. Addition of tamoxifen to CMF had no effect on disease-free survival in ER + patients with 1-3 positive axillary lymph nodes or in patients with ER- tumors. Addition of BCG vaccinations had no discernible effect on disease-free survival. ER measurements in the primary tumor provide important prognostic information regardless of treatment, with ER + patients having increased overall survival after 6 years. Further follow-up is needed to determine whether tamoxifen is delaying recurrence or preventing it in a subset of these patients.