Etoposide, mitomycin, and methotrexate combination in heavily treated breast cancer: a retrospective study

Background Since 2004, metastatic breast cancer patients pretreated with anthracyclines, taxanes, and capecitabine have been treated in our institution with a combination of mitomycin C, methotrexate, and VP-16 (VMM). We report in this study a retrospective analysis of the activity and safety of the VMM combination. Methods Patients were treated with a combination of VP-16 (100 mg/m(2) on day 1), mitomycin C (MMC, 10 mg/m(2) on day 1), and methotrexate (MTX, 12.5 mg/m(2) twice a day on day 2 and 3) in a 21-day cycle. Results Seventy-five patients were treated. Median age was 48 years. A total of 256 cycles were administered. Median relative dose intensities were 0.87, 0.87, and 0.95 for VP-16, MMC, and MTX, respectively. Objective response rate was 31%, with a clinical benefit rate of 47%. Median response duration was 5.8 months. Median disease stabilization duration was 9.1 months. Median progression-free survival (PFS) was 4.2 months with a 14% 1-year PFS rate. Median overall survival (OS) was 6.2 months, with a 25% 1-year OS rate. Myelosuppression was the most common toxicity. The most commonly reported extra-hematological adverse event (AE) was fatigue. Emesis and alopecia were rarely reported. Conclusions This combination appears to be effective and well tolerated in this heavily pretreated metastatic breast cancer population.