Ascites regression following neoadjuvant chemotherapy in prediction of treatment outcome among stage IIIc to IV high-grade serous ovarian cancer

BACKGROUND: No consensus exists on the outcome-related factors of interval debulking surgery (IDS) in patients with advanced high-grade serous ovarian cancer (HG-SOC) who underwent neoadjuvant chemotherapy (NAC). This study aimed to explore the optimal timing for IDS and the prognosis-associated factors of International Federation of Gynecology and Obstetrics stage IIIc to IV HG-SOC patients. METHODS: A total of 160 IIIc to IV stage HG-SOC patients were retrospectively analyzed. Patients with large volume ascites underwent NAC and subsequent IDS from the Jiangsu Institute of Cancer Research between 1993 and 2013. The outcome of IDS-associated factors was explored by logistic regression. To predict IDS outcome, the potential values of serum CA-125 levels and CA-125 decreasing kinetics were determined by the receiver operating characteristic curve. The associations between survival durations and covariates were assessed by Cox proportional hazards model and log-rank test. RESULTS: Optimal IDS was achieved in 80.6% of HG-SOC patients who underwent NAC. Multivariate analyses revealed that ascites regression (p = 0.01), serum CA-125 level (p = 0.02), and CA-125 decreasing kinetics (p = 0.01) were independent optimal IDS predictors. CA-125 decreasing kinetics, IDS outcome, and ascites volume were independently associated with overall survival (OS) (p = 0.04, p < 0.01, p = 0.03, respectively) and progression-free survival (PFS) (p < 0.01, p < 0.01, p = 0.02, respectively). Patients who exhibited disappearance of ascites (<500 ml) had longer PFS (19.7 months vs.14.9 months) and OS (32.1 months vs. 26.0 months) than patients who exhibited residual ascites (≥500 ml). Subsets with higher CA-125 decreasing kinetics (≥2.2) had longer PFS (21.4 months vs.13.1 months) and OS (29.6 months vs.26.8 months) than counterparts (kinetics < 2.2). CONCLUSIONS: Ascites regression and CA-125 decreasing kinetics were independently associated with surgical outcome and prognosis in advanced HG-SOC patients who underwent NAC.