Positive ascites cytology in interval debulking surgery predicts poor outcomes of advanced epithelial ovarian cancer achieving complete tumor resection.

Positive ascites cytology is a known poor prognostic factor in ovarian cancer, but its impact after neoadjuvant chemotherapy (NAC) with complete tumor resection remains unclear. Among 4944 patients, 191 underwent primary debulking surgery (PDS) and 59 underwent NAC followed by interval debulking surgery (NAC-IDS), all achieving R0 resection at stage III. Kaplan-Meier, univariate, and multivariate analyses were performed. Positive ascites cytology was independently associated with higher recurrence and mortality at 5 years [odds ratio (OR) of recurrence at 5 years = 2.412, P = 0.003; OR of mortality at 5 years = 2.025, P = 0.010]. Subgroup analysis showed greater risk in NAC-IDS than in PDS [NAC-IDS: HR of PFS = 2.003, P = 0.029; HR of OS = 3.259, P = 0.006; PDS: HR of PFS = 1.549, P = 0.031; HR of OS = 1.789, P = 0.018]. The interaction effect analysis suggested that positive ascites cytology was associated with a higher risk of mortality at 5 years in NAC patients than in PDS patients [OR of NAC-IDS = 3.722, OR of PDS = 1.151, OR for interaction = 3.234]. The present results indicate that positive ascites cytology in NAC-IDS predicts poor survival outcomes in patients with advanced ovarian cancer.