Phase II evaluation of paclitaxel and carboplatin in the treatment of carcinosarcoma of the uterus: A gynecologic oncology group study

Purpose: Platinum and taxane compounds have demonstrated activity in uterine carcinosarcoma (malignant mixed Mullerian tumor). Ifosfamide plus paclitaxel is the regimen with established superiority based on a randomized phase III trial conducted through the Gynecologic Oncology Group. However, the toxicity, multiday schedule, and limited activity of this regimen support further development of novel regimens. Our primary objective was to estimate the antitumor activity and toxicity of paclitaxel plus carboplatin in patients with uterine carcinosarcomas. Patients and Methods: Eligible patients had advanced stage (III or IV), persistent or recurrent measurable disease, and no prior chemotherapy. Patients received paclitaxel at 175 mg/m² intravenously (IV) over 3 hours plus carboplatin (area under the serum concentration-time curve = 6) IV over 30 minutes every 3 weeks until disease progression or until adverse effects occurred. Common Terminology Criteria for Adverse Events v3.0 was used to grade adverse events. Results: Fifty-five patients were entered onto the study with nine being excluded from analysis, leaving 46 evaluable for analysis. Treatment was well tolerated with expected hematologic toxicity and minimal nonhematologic grade 4 toxicity (one cardiovascular and two pain) with 59% of patients completing six or more cycles of chemotherapy. The proportions of patients with confirmed complete and partial responses were 13% and 41%, respectively, resulting in a total overall response rate of 54% (95% CI, 37% to 67%). Conclusion: Paclitaxel plus carboplatin demonstrates antitumor activity against uterine carcinosarcoma with acceptable toxicity and warrants further evaluation in phase III randomized trials.