Thirty-five patients (pts.) with advanced renal cell carcinoma were treated with a combination of vinblastine (5 mg/m2/IV) plus epirubicin (50 mg/m2/IV) every 3-4 weeks, alpha-2-A-interferon (9 x 10(6) U/IM 3 times in the 1st week, then 18 x 10(6) U/IM 3 times weekly), and medroxyprogesterone acetate (2,000 mg/os/day plus 500 mg IM/week). Thirty-one patients were males and 4 were females with a median age of 63 years (range 35-75) and median performance status of 70% (range 50-90%). We observed nine partial remissions (26%) with median duration of 40 weeks (range 20-232+). Fifteen pts. had no change (43%) while 11 pts. progressed (31%). The main side-effects were: leukopenia (29/35, 83%) with median nadir of 3,100 WBC/mm3 (range 510-3,990) and fever (32/35, 91%). Thrombocytopenia occurred in 4 pts. (11%), anemia in 5 (14%), asthenia in 12 (34%), nausea/vomiting in 12 (34%), alopecia in 8 (23%) and stomatitis in 3 (8.5%). Two patients stopped the therapy with medroxyprogesterone acetate because of muscular cramps. Median survival was 65 weeks (range 6-327+). We conclude that the combination of recombinant alpha 2A-interferon-vinblastine-epirubicin and medroxyprogesterone acetate has modest but definitive activity in patients with advanced renal cell carcinoma.