3-4 Cycles vs 6 Cycles NACT in Advanced Stage Epithelial Ovarian Cancer: Survival is not Determined by the Number of NACT Cycles

Abstract

Introduction: The aim of this study was to compare the disease-free survival (DFS) and overall survival (OS) of patients who underwent interval cytoreductive surgery after 3-4 cycles or 6 cycles of neoadjuvant chemotherapy (NACT) in advanced epithelial ovarian cancer patients. Methods: Out of 219 patients with advanced epithelial ovarian cancer,123 patients received 3-4 cycles and 96 patients received 6 cycles of platinum-based NACT. Afterwards, laparotomy was performed for interval cytoreductive surgery. Results: No statistically significant difference was found for DFS and OS of the patients who received 3-4 cycles and those who received 6 cycles of NACT (HR:1.047,95.0%CI [0.779–1.407]; p:0.746 for DFS, and HR:1.181,95.0% CI [0.818–1.707]; p:0.368 for OS). Evaluating 123 patients who received 3-4 cycles of NACT;87 patients (70.7%) without macroscopic residual tumor after interval cytoreductive surgery had significantly longer DFS and OS compared to 36 patients(29.3%) with any residual tumor (HR:1.830,95.0% CI [1.194-2.806]; p:0.003 for DFS, and HR:1.946,95.0% CI [1.166-3.250]; p:0.009 for OS).96 patients who received 6 courses of NACT were evaluated;63 patients (65.6%) without macroscopic residual tumor after interval cytoreductive surgery had significantly longer DFS and OS than 33 patients (34.4%) with any residual tumor (HR:1.716,95.0% CI [1.092-2.697];p:0.010 for DFS, and HR:1.921,95.0%CI [1.125-3.282]; p:0.013 for OS). Conclusion:In patients with advanced ovarian cancer,there is no significant difference in DFS and OS between 3-4 cycles or 6 cycles of NACT.The most important factor determining survival is whether macroscopic residual tumor tissue remains after interval cytoreductive surgery following NACT.