Long-term prognostic significance of ascites cytology in ovarian cancer cases in which R0 resection was achieved in the initial surgery: a multi-institutional retrospective cohort study.

Abstract

Background: In ovarian cancer (OvCa), achieving complete resection (RO) in initial surgery is crucial for improving prognosis. However, patients with undetected microscopic metastasis post-RO surgery often have poorer outcomes. This study explores prognostic factors for OvCa patients who underwent RO surgery, focusing on the role of ascites cytology as an indicator of microscopic peritoneal metastasis.

Methods: We analyzed data from 975 OvCa cases in the Tokai Ovarian Tumor Study Group database (1986-2019). Excluding patients without chemotherapy or with distant metastasis, we examined prognostic factors using Cox regression analysis. Propensity score (PS) methods balanced the cytology-positive and -negative groups, with subgroup analysis for clinical stage and ascites volume.

Results: Multivariate analysis identified FIGO stage III and positive ascites cytology as poor prognostic factors for overall and progression-free survival. After PS adjustment, positive ascites cytology also shortened progression-free intervals post-recurrence, especially in cases with peritoneal or lymph node metastasis. Subgroup analysis revealed a more substantial prognostic impact of positive ascites cytology in early-stage cases.

Conclusion: The present results suggest that in OvCa patients with the R0 status, the presence of tumor cells in ascites is an independent negative prognostic factor and may be an indicator of peritoneal micro-metastasis.