56 patients with advanced breast carcinoma, primarily or secondarily resistant to a four drug combination including Adriamycine, Vincristine, Cyclophosphamide and 5 Fluoro-Uracile, entered a phase II trial using association of VM 26, Mitomycine C and Methotrexate. The tolerance was generally good, but 17 clinical manifestations of toxicity were observed out of 216 cycles of treatment (7,8%). THese mucosal and haematologic disorders have incitated to secondarily reduce of 20 per cent the current doses of Methotrexate. 28 patients out of 53 (53%) have objectively responded to treatment and in 16 of them, major responses (C.R + P.R. > 50%) were observed (30%). The median of survival responders was 11 months. The critical analysis of responses by site showed 53 per cent of objective regression of lung metastasis which appears higher than the incidence of response observed after treatment with drug combination including Adriamycine.