High-dose chemotherapy with mitoxantrone + melphalan and autologous stem cell rescue in metastatic breast cancer patients: a study of feasibility and tolerability.

Hematological and extra-hematological toxicity of mitoxantrone-containing regimens with autologous stem cell rescue was evaluated in 32 metastatic breast cancer patients. The schedule was the final part of two high-dose chemotherapy programs, including an induction phase with three courses of conventional chemotherapy with epirubicin (120 mg/m2) and cyclophosphamide (600 mg/m2) plus three courses of docetaxel (100 mg/m2) and a first high-dose chemotherapy consisting of cyclophosphamide (6000 mg/m2), thiotepa (500 mg/m2) and carboplatin (800 mg/m2) or melphalan (160 mg/m2) plus thiotepa (600 mg/m2). The final second autograft phase included mitoxantrone (60 mg/m2) associated with melphalan (160 mg/m2) and autologous stem cell rescue infusion. The median duration of severe neutropenia and thrombocytopenia was 9 (range, 7-13) and 11.5 (range, 9-29) days. The median number of units of erythrocytes and platelets transfused was 1 (0-11) and 4 (1-9), respectively. Fever for a median of 2 (0-8) days developed in 71.8% of the patients. Mucositis was observed in 81.2% (WHO grade 3-4 in 25%). No acute or late cardiac toxicity was observed. One patient died because of a transplant-unrelated cause. The response according to the program phase showed an increased rate of complete response, from 12.5% at the end of conventional chemotherapy to 21.9% after the first high-dose chemotherapy course, to increase to 43.9% after the treatment with mitoxantrone-melphalan. We conclude that a conditioning regimen with high dose mitoxantrone-melphalan fits well within the high-dose chemotherapy program.