5-Fluorouracil, adriamycin and cyclophosphamide combined with high-dose medroxyprogesterone acetate in advanced breast cancer.

Seventy-six patients with metastatic breast cancer were treated with fluorouracil, adriamycin (doxorubicin) and cyclophosphamide (FAC) plus high-dose medroxyprogesterone acetate (HD-MPA). MPA was given for 21 days at the dose of 500 mg/day i.m., then on a randomized basis, either 500 mg/week i.m. (FAC+HD-MPA i.m.) or 300 mg/day p.o. (FAC+HD-MPA p.o.). Objective response rates were 79% in 39 patients on FAC+HD-MPA i.m. and 73% in the 37 patients on FAC+HD-MPA p.o. There was no significant difference in the median duration of response and median survival for the 2 regimens (respectively, 17 months and 22 months, and 15 months and 21 months for FAC+HD-MPA i.m. and FAC+HD-MPA p.o.). Toxicity was mild and similar in both groups. Although FAC+HD-MPA was highly effective, at present it is difficult to select which regimen provides the best initial treatment for metastatic breast cancer.