Combination chemotherapy compared to tamoxifen as initial therapy for stage IV breast cancer in elderly women.

In a randomized crossover study, 181 patients over the age of 65 with recurrent breast cancer received either tamoxifen or cyclophosphamide, methotrexate, and fluorouracil (CMF). After progression on tamoxifen, a hormone withdrawal period was required. Because of altered pharmacokinetics with aging, creatinine clearance was used in calculating the dose of CMF. Response rates were 45% on tamoxifen and 38% on CMF, with median durations of 10.4 and 7.9 months, respectively. Survival rates tended to favor tamoxifen as the initial treatment even in estrogen-receptor-negative patients. Additional disease control with hormone withdrawal occurred in 23% of patients, and this benefit was highly correlated with prior hormone response. We conclude that initiation of hormone therapy rather than CMF chemotherapy is justified in almost all situations in elderly patients, and combination chemotherapy, is safe and useful after hormone failure if modified on the basis of renal dysfunction.