Adjuvant therapy of premenopausal and menopausal high-risk breast cancer patients. Present status of the Danish Breast Cancer Cooperative Group Trials 77-B and 82-B.

Abstract

From September 1977 to November 1987 high-risk (i.e. with positive axillary lymph nodes, or tumor size greater than 5 cm or skin/facia invasion) premenopausal and menopausal breast cancer patients have been included in 2 randomized trials. In both trials the primary surgical treatment was total mastectomy with axillary sampling. In the first trial (DBCG 77-B) 1034 patients all received postoperative radiotherapy (RT) and were further randomized to 1) no systemic treatment (0), 2) cyclophosphamide (C), or 3) cyclophosphamide + methotrexate + 5-fluorouracil (CMF). The chemotherapy was given for 1 year. With a median observation time of 7 years the actuarial survival after 9 years is 50, 60 and 65% respectively. Retrospectively, the survival benefit was observed to be most pronounced in patients with tumor size less than or equal to 5 cm and with less than or equal to 3 positive lymph nodes. In the subsequent study initiated in 1982 (82-B) all patients received CMF for 9 months. Furthermore they were randomized to 1) RT, 2) no further treatment, or 3) tamoxifen (TAM) for 1 year. As of November 1, 1987, 1308 patients have been included. At 4 years and with a median observation time of 2 years the survival is similar in the 3 groups. In conclusion, in high-risk premenopausal and menopausal patients adjuvant chemotherapy combined with RT resulted in a 20-30% relative reduction in mortality at 9 years compared with RT alone. Preliminary analysis of adjuvant CMF + RT, compared with CMF alone or with CMF + TAM, shows after a median observation time of more than 2 years no significant survival differences.