Effectiveness of MAID Therapy against Metastatic Malignant Phyllodes Tumors and Stromal Sarcoma of the Breast

Abstract

Malignant phyllodes tumors and stromal sarcoma are rare malignancies of the breast. The efficacy of systemic chemotherapy against metastatic malignant phyllodes tumors and metastatic stromal sarcoma remains unknown. Patients and Methods: We retrospectively analyzed 8 patients with metastatic malignant phyllodes tumors or stromal sarcoma, who were treated with MAID (mesna, doxorubicin, ifosfamide, dacarbazine) chemotherapy. The MAID therapy was administered intravenously every 4 weeks as follows: mesna 1,500 mg/m2/day, days 1-4; doxorubicin 20 mg/m2/day, days 1-3; dacarbazine 300 mg/m2/day, days 1-3; ifosfamide 2,500 mg/m2/day, days 1-3. Results: Although complete response was not achieved in any of the patients, 4 of the 8 patients showed partial response. The median time to disease progression was 74 days, and the overall median survival was 148 days. Grade 3 or more severe hematological toxicity was encountered in all patients. Conclusion: MAID therapy for metastatic malignant phyllodes tumors and stromal sarcoma was moderately effective in terms of tumor reduction. However, the treatment was associated with severe toxicity.