Intraperitoneal recombinant alpha-2-interferon alternating with cisplatin as salvage therapy for minimal residual-disease ovarian cancer: a phase II study.

A phase II study was initiated in March 1987 at the Regina Elena National Cancer Institute of Rome to evaluate the efficacy of alternating intraperitoneal (IP) recombinant alpha-2-interferon (r-alpha 2-IFN) and cisplatin (DDP) as salvage therapy for less than or equal to 5 mm residual-disease (RD) ovarian carcinoma. Fourteen assessable patients entered the study. All had received prior chemotherapy (11 with DDP-based regimens); five patients had macroscopic RD (less than or equal to 5 mm), and nine had microscopic RD (histologically positive random biopsies and/or positive cytology and immunocytochemical tests). The response to IP immunochemotherapy was evaluated by laparotomy. Pathologic complete remissions (PCRs) were achieved in seven patients (50%) who have remained free of disease with a median follow-up of 22+ months (range, 11+ to 30+ months). Six patients achieved a stable disease and one presented disease progression. With the exception of chemical peritonitis-induced adhesions, no limiting toxicity was observed. The results obtained in this small, highly selected series demonstrate that a high PCR rate may be obtained with IP immunochemotherapy with DDP and r-alpha 2-IFN as salvage therapy in residual ovarian carcinoma less than or equal to 5 mm after first-line chemotherapy also including intravenous (IV) DDP. Larger comparative studies must be conducted to establish the potential role of IP DDP and r-alpha 2-IFN as compared with either of the single treatments.