A randomised comparative trial of mitozantrone/methotrexate/mitomycin C (MMM) and cyclophosphamide/methotrexate/5 FU (CMF) in the treatment of advanced breast cancer

Mitozantrone (Novantrone) has recently been incorporated into a new combination chemotherapy regimen with mitomycin-C and methotrexate (MMM) against advanced breast cancer. We have compared MMM (mitozantrone 8 mg m-2 i.v. q 3 weekly, methotrexate 35 mg m-2 i.v. q 3 weekly, mitomycin-C 8 mg m-2 i.v. q 6 weekly) with CMF (cyclophosphamide 100 mg orally, days 1-14, methotrexate 35 mg m-2 i.v., days 1 and 8, 5-FU 1,000 mg i.v., days 1 and 8, q 4 weekly), each regimen with folinic acid rescue, in a randomised trial, 29/57 evaluable patients treatment with MMM achieved an objective response (51%) compared with 33/55 treated with CMF (60%). Overall median survival was 16 months for MMM and 12 months for CMF. Subjective toxicity was low for both regimens and the only significant difference was in incidence of diarrhoea (50% for CMF vs 21% for MMM). Haematological toxicity was similar, leading to treatment delays and/or dose reductions in 35% patients with CMF vs 43% with MMM. Thrombocytopenia was significantly increased in MMM (34% vs 14%). No clinical cardiotoxicity was seen, but a significant reduction in left ventricular ejection fraction occurred in four patients on CMF vs 2 on MMM. MMM is an active, well tolerated new chemotherapy regimen for advanced/metastatic breast carcinoma with an efficacy and toxicity spectrum very similar to CMF.