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

Tugan Bese, Elifnur Bicer, Basak Ozge Kayan, Sait Sukru Cebi, Abdullah Serdar Acikgoz, Hande Turna, Fuat Demirkiran

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. 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. 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). 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.