Implementation of Extensive Cytoreduction Resulted in Improved Survival Outcomes for Patients with Newly Diagnosed Advanced-Stage Ovarian, Tubal, and Peritoneal Cancers

Background: Residual disease (RD) after primary debulking surgery (PDS) is one of the main factors driving ovarian cancer prognosis. The primary end point of this study was assessment of the impact that surgery had on survival outcomes for patients with advanced ovarian cancer. Methods: Data on the effect of newly diagnosed advanced-stage ovarian, tubal, and peritoneal cancers were analyzed during two study periods (T1: 2001–2006 and T2: 2007–2012), in which the concepts of optimal and complete cytoreduction were introduced and implemented. Results: In this study, 260 patients (36%) had surgery during T1 and 462 patients (64%) had surgery during T2. The rate of PDS increased, from 55.4% (144/260) during T1 to 85.5% (395/462) during T2 (p < 0.001). At the time of PDS, complete resection (RD0) was achieved for 45.1% of the patients during T1 and 76.7% of the patients during T2 (p < 0.001), whereas optimal resection (RD < 1 cm) was achieved for 60.4% of the patients during T1 and 85.3% of the patients during T2 (p < 0.001). Disease-free survival improved during the study periods (p = 0.006). Overall survival was similar in T1 and T2 (p = 0.18). The preoperative CA125 level, disease stage, and RD remained independently associated with disease-free survival (p ≤ 0.05). The performance of interval debulking surgery (IDS) instead of PDS correlated with worse survival outcomes (hazard ratio [HR] 1.47; 95% confidence interval [CI] 1.24–1.92; p = 0.02), whereas achievement of RD0 and RD < 1 cm independently improved overall survival (HR 0.45; 95% CI 0.22–0.91; p = 0.02 for RD0 and HR 0.47; 95% CI 0.23–0.96; p = 0.03 for RD0). Conclusions: The implementation of extensive cytoreduction allows improvement of patient outcomes. Further studies are needed to assess the risk-to-benefit ratio between PDS and IDS and to identify patients who benefit much more from one treatment method than from another.