Carboplatin, ifosfamide, and mesna (CIM) for the treatment of gynecological carcinosarcoma
e16539 Background: A GOG trial comparing cisplatin/ifosfamide/mesna chemotherapy versus whole abdominal irradiation for FIGO stages I-IV carcinosarcoma (CS) showed an estimated median survival (MS) of 50 months for chemotherapy but high toxicity. This study investigates the efficacy and tolerability of a novel regimen using carboplatin AUC 5, ifosfamide 3 g/m2 and mesna 1 g/m2 (CIM) in both the adjuvant and metastatic setting. Methods: Retrospective analysis of women with CS treated from May 1997-May 2007 with CIM (group 1) versus other chemotherapy regimens (group 2). Toxicity was graded according to the Common Toxicity Criteria and MS estimated using the Kaplan-Meier method. Results: Of 51 eligible women (median age 71 years) 35 (69%) had stage 3 or 4 disease. 35/51 (69%) received chemotherapy; 2 with stage 1c disease received pelvic radiotherapy (pRT) alone whilst the remaining 14 were unfit for any treatment. Median follow-up for the treated patients is 45 months. 11/35 patients (31%) received CIM as first-line chemotherapy. Other regimens included: carboplatin (n = 14); carboplatin/paclitaxel (n = 3); carboplatin/epirubicin (n = 3); carboplatin/doxorubicin (n = 2); doxorubicin/ifosfamide (n = 1); cisplatin/ifosfamide (n = 1). 20/35 (57%) received adjuvant chemotherapy (AC) of which 8 received CIM; 11/20 patients also received adjuvant pRT. MS in the CIM AC group is 54.7 months compared to 37.4 months for other regimens. 3/8 patients (37.5%) in the CIM arm developed recurrent disease compared to 9/12 (75%) for other regimens. 4/16 patients received CIM as first- or second-line palliative chemotherapy. All patients responded of whom 2 achieved clinical and radiological complete response (CR). One woman subsequently relapsed and achieved a second CR with CIM. MS for all chemotherapy-treated patients is 54.7 months (group 1) versus 20.6 months (group 2) (p = 0.07). No patients in group 1 experienced any grade 3/4 toxicity and all patients completed the prescribed treatment. There were 2 unexpected treatment-related deaths in group 2, one of whom received carboplatin/paclitaxel and the other carboplatin/epirubicin. Conclusions: CIM appears to be efficacious and well tolerated in the treatment of CS and merits further investigation in clinical trials. No significant financial relationships to disclose.