Intraperitoneal recombinant interferon gamma in ovarian cancer patients with residual disease at second-look laparotomy

Purpose: The purpose of this study was to evaluate the efficacy and tolerance of recombinant human interferon gamma (rIFN-gamma) as second-line treatment in patients with persistent disease at second-look laparotomy. Patients and Methods: One hundred eight patients with residual disease at second-look laparotomy were treated with rIFN-gamma (2O x 10(6) IU/m(2)) administered intraperitoneally (IP) twice a week for 3 to 4 months. In the absence of clinically assessable disease, response to rIFN-gamma was assessed with a third-look laparotomy. Results: Of 98 assessable patients, 31 (32%) achieved a surgically documented response, including 23 patients (23%) with a complete response (CR). The age and size of residual tumor were significant prognostic factors for the response to rIFN-gamma. A 41% CR rate was observed in 41 patients younger than 60 years and with residual tumor less than 2 cm. The probability of response was independent of previous response to first-line chemotherapy. The median duration of response was 20 months and the 3-year survival rate in responders was 62%. Response to rIFN-gamma was the most significant prognostic factor for survival of patients with residual disease. Adverse events included fever, flu-like syndrome, neutropenia, and liver enzyme disturbances. No significant peritoneal fibrosis was noted. Conclusion: These results support the potential interest of IP rIFN-gamma as adjuvant treatment in ovarian cancer. Controlled prospective trials are required to determine its place in the therapeutic strategy of this malignancy. (C) 1996 by American Society of Clinical Oncology.