Cancer and Leukemia Group B adjuvant chemotherapy trials in postmastectomy breast cancer patients.

The Cancer and Leukemia Group B (CALGB) has conducted two recent trials of adjuvant chemotherapy in breast cancer patients found to have lymph node metastases after mastectomy. The first trial in 772 evaluable patients demonstrated an advantage of five drugs (CMFVP) over three drugs (CMF). This advantage is seen in the group of patients who have been followed the longest period of time (median 52 months). When the more recent entries are also included in the evaluation, the benefit is seen only in women with more than three positive nodes. The advantage of five drugs over three is seen first and most dramatically in those patients with the greatest burden of disease and only later, and less dramatically, appears in groups with fewer positive lymph nodes. The second trial examines the effects of two scheduling methods of CMFVP and the value of a non-cross-reacting drug combination during the second six months of a year of adjuvant therapy.