Mitoxantrone, methotrexate, and 5-fluorouracil (MMF) in hormone-refractory advanced breast cancer

Thirty-nine patients with metastatic breast cancer who had not received prior chemotherapy for metastatic disease were treated in a phase II trial with a combination of mitoxantrone (10 mg/m2), methotrexate (40 mg/m2) and 5-fluorouracil (600 mg/m2) i.v. every 3 weeks (MMF). Thirty-three patients could be evaluated with regard to response and toxicity. Objective response was observed in 33% (3/33 complete responses, 8/33 partial responses). Dominant sites of disease were bone (16 patients), liver (7 patients), skin/lymph node (7 patients), lung (1 patient) and breast (2 patients). Responses occurred in bone (4/16), liver (3/7) and skin/lymph node (4/7). Moderate to severe alopecia (grade 3-4 WHO criteria) occurred in 3/33 (10%) patients; moderate to severe nausea and vomiting in 2/33 (6%) patients. Haematological toxicity consisted of predominantly leukopenia. Leukopenia grade 3-4 (nadir below 2000 x 10(9)/litre) occurred in 22/33 (67%) patients; thrombocytopenia grade 3-4 (nadir below 50,000 X 10(9)/litre) occurred in 3 patients (9%). The MMF regimen appears to be effective. The non-haematological toxicity compares favourably with that of the more commonly used chemotherapy regimens, but the anti-tumour activity may be less.