Intraperitoneal Interferon-α in Residual Ovarian Carcinoma: A Phase II Gynecologic Oncology Group Study

Abstract Objective. The purpose of this study was to confirm the activity of interferon-α intraperitoneally in minimal residual epithelial ovarian cancer in a Phase II multi-institutional trial and to investigate the activity of the agent based on prior response to first-line platinum compounds. Methods. Ninety-two patients with minimal residual ( Results. Eighty patients were clinically evaluable for toxicity only (48 favorable, 32 unfavorable) and 46 of them were evaluable for response, of whom 25 were favorable (platinum sensitive) and 21 unfavorable (platinum resistant). In the favorable group, there was a 28% surgically documented response rate (7/25 patients): 16% (4/25) had complete responses (negative reassessment operation), 12% (3/25) had partial responses, 32% (8/25) were nonresponders, and 40% (10 patients) developed progressive disease before planned reassessment operation. In the unfavorable group, there were no responding patients: 6 were nonresponders at reassessment operation and 15 developed progressive disease before planned reassessment operation. Of the 80 patients evaluable for toxicity, the most common adverse effects that were more than grade 2 were gastrointestinal (12; 15%), fever (8; 10%), neutropenia (7; 9%), and leukopenia (6; 8%). Grade 4 toxicity was seen in 5 patients; each had fever and gastrointestinal toxicity, and 1 each had neutropenia and thrombocytopenia. Conclusions. Interferon-α is an active and generally well-tolerated agent in favorable patients with minimal residual epithelial ovarian cancer at second-look surgery. These results are comparable to those achieved with cytotoxic chemotherapy. If Phase III trials are considered in the patients with minimal residual ovarian cancer, they should be limited to the platinum-sensitive patient population.