Southwest Oncology Group Trial S9912: Intraperitoneal cisplatin and paclitaxel plus intravenous paclitaxel and pegylated liposomal doxorubicin as primary chemotherapy of small-volume residual stage III ovarian cancer

Objective: While primary cisplatin-based intraperitoneal chemotherapy has been shown to favorably impact survival in small-volume residual advanced ovarian cancer, there is a need to develop strategies that improve the effectiveness of this approach. Methods: A multi-center phase 2 trial was conducted that added intravenous pegylated liposomal doxorubicin (day 8; 30-40 mg/m²) to a regimen of intraperitoneal cisplatin (day 2; 75 mg/m²) and intravenous (day 1; 135 mg/m²) plus intraperitoneal (day 8; 60 mg/m²) paclitaxel. Treatment was initially delivered on an every 3-week schedule, but was modified to an every 4-week program due to excessive toxicity. Patients were to receive 6 cycles of this regimen. Results: Of 68 patients entering this trial, 63 patients were eligible and evaluable, of whom 39 (62%) completed 6 cycles. Overall, 32 (51%) experienced at least 1 grade 4 or worse toxicity (most commonly hematologic) including 5 treatment-related deaths. Median progression-free survival (PFS) was 25 months (2-year PFS: 52%) and median overall survival 51 months, an outcome similar to previous reports of cisplatin-based intraperitoneal chemotherapy in comparable patient populations. Seventeen patients (27% of all eligible patients) were without evidence of disease recurrence > 4 years following entry into the trial. Conclusion: Both the overall trial outcome, and specifically the excessively severe systemic toxicity of this regimen would prevent its future development in this exact form. The provocative PFS in a subset of individuals should encourage the development of alternative strategies designed to optimize the delivery of regional therapy in ovarian cancer management.