Phase II Study of Carboplatin and Weekly Irinotecan Combination Chemotherapy in Recurrent Ovarian Cancer: A Kansai Clinical Oncology Group Study (KCOG0330)

Background: A multicenter phase II trial was conducted to evaluate the efficacy and toxicity of irinotecan plus carboplatin chemotherapy in patients with epithelial ovarian cancer (EOC). Patients and Methods: Patients with either radiologically- or serologically-recurrent EOC were administered intravenous irinotecan (60 mg/m(2); days 1 and 8) and carboplatin area under the curve of 5 mg/ml/min (day 1), repeated every 21 days. The primary end-point was response rate (RR), while the secondary end-points were adverse events and progression-free survival (PFS). Results: Between 2005 and 2009, 40 patients (median age=59 years) with EOC were enrolled. Intention-to-treat analysis showed an RR of 43% [95% confidence interval (CI)=27-58%]. For patients with a platinum-free interval (PFI) of <6 months, overall RR based on RECIST was 21% (95% CI=0-43%) and median PFS was 3.7 months (95% CI=2.5-7.7 months), while those in patients with PFI >= 6 months were 52% (95% CI=31-74%) and 9.1 months (95% CI=7.9-11.2 months), respectively. Grade 314 toxicity encountered during the first cycle included G3/G4 neutropenia in 65% of patients (12114), G3/G4 thrombocytopenia in 48% (1811), G3 febrile neutropenia in 5% (2), G3 nausea in 5% (2), G3 diarrhea in 5% (2), and G3 fatigue in 5% of patients (2). Conclusion: This carboplatin plus irinotecan combination demonstrated a modest activity in recurrent EOC. However, considering its hematological toxicities, the regimen should be further investigated to establish the feasibility of the modified dose for platinum-sensitive disease.