Prognostic Value of Residual Tumor Size in Patients With Epithelial Ovarian Cancer FIGO Stages IIA-IV Analysis of the OVCAD Data

Objective: The objective of the study was to evaluate the prognostic impact of residual tumor size after cytoreductive surgery in patients with epithelial ovarian cancer. Methods: In this prospective, multicenter study, 226 patients with epithelial ovarian cancer (International Federation of Gynecology and Obstetrics stages IIAYIV) were included. Patients were treated with cytoreductive surgery and adjuvant platinum-based chemotherapy. Univariate and multivariable survival analyses were performed to investigate the impact of residual tumor size on progression-free and overall survival. Results: In 69.4% of patients, surgery resulted in complete tumor resection; minimal residual disease (<= 1 cm) was achieved in 87.2% of patients. Advanced tumor stage was associated with a lower rate of complete tumor resection (P < 0.001). After cytoreductive surgery, 3-year overall survival rates were 72.4%, 65.8%, and 45.2% for patients without, with minimal, and with gross residual disease (>1 cm), respectively (P < 0.001). Multivariable survival analysis revealed residual tumor size (P = 0.04) and older patient age (P = 0.02) as independent prognosticators for impaired overall survival. Complete cytoreduction was predictive for a higher rate of treatment response (P = 0.001) andwas associated with prolonged progression-free and overall survival (P < 0.001 and P = 0.001). Conclusions: The size of residual disease after cytoreduction is one of the most crucial prognostic factors for patients with ovarian cancer. Patients after complete cytoreduction have a superior outcome compared with patients with residual disease. Leaving no residual tumor has to be the aim of primary surgery for ovarian cancer; therefore, patients should receive treatment at centers able to undertake complex cytoreductive procedures.