Prednimustine, methotrexate, 5-fluorouracil, mitoxantrone and tamoxifen for advanced breast cancer in postmenopausal women. A phase II trial.

A phase II trial in postmenopausal women with advanced breast cancer naive to cytotoxic treatment for recurrent disease was performed with a combinated chemo-endocrine regimen of prednimustine, methotrexate, mitoxantrone, 5-fluorouracil, and tamoxifen. Thus we replaced the most toxic agents--cyclophosphamide and doxorubicin often used in combinations--with prednimustine and mitoxantrone respectively, which are supposed to be equally efficient but less toxic. Seventy-seven patients were registered but 6 were ineligible. Complete response was obtained in 11%, partial response in 29%, no change in 29%, and progressive disease in 31%. Median duration of response was 18.5 months, time to disease progression 9.2 months, and survival 16.0 months. Toxicity was modest; 61% had no or only moderate alopecia not necessitating a wig, 59% had no or only moderate, if any, nausea. Bone marrow suppression, especially thrombopenia, was a major dose limiting factor. This regimen seems to be effective and have low toxicity in advanced breast cancer in postmenopausal women.