793 Clinical implications of pleural effusion in advanced stage epithelial ovarian cancer- insights from a tertiary cancer centre in North East India

Introduction/Background Presence of malignant pleural effusion is an important prognostic marker in ovarian cancer. While this group of patients fare poorly as documented in the literature, there is a paucity of data regarding the significance of negative pleural fluid cytology. With this background a retrospective study was planned to address this lacunae. Methodology A retrospective descriptive study was conducted in a tertiary cancer centre between January 2021 to December 2022. All patients who presented with advanced stage epithelial ovarian cancer (Stage 3 and stage 4) with pleural effusion were included in the study as cases and their counterparts without pleural effusion were analysed as controls. All the patients had their pleural effusion analysed by a trained pathologist. Patients were analysed in 3 groups (i) Those with cytology positive pleural effusion (CPPE). (ii)Those with cytology negative pleural effusion (CNPE). (iii) Patients without pleural effusion (NPE). Only those patients who completed their treatment were included and those who defaulted were excluded from the study. Survival analysis was done using Kaplan Meier curves (SPSS 29). Results A total of 119 patients were included. Thirteen patients (10.7%) were CPPE, 23(19.3%) were CNPE and 81(70%) were NPE. Mean PFS for CPPE was 9 months, CNPE was 14 months and NPE was 19 months. Mean OS for CPPE was 11 months, CNPE was 18 months and NPE was 32 months. On comparing the survival curves the results were found to be statistically significant for PFS (p<0.001) and OS (p<0.001). Conclusion Patients with CNPE group fared poorly compared to the NPE group. We propose routine video assisted thoracoscopy in all CNPE patients as a diagnostic armamentarium during evaluation to avoid missing out pleural disease and subsequent management. Disclosures Nothing to declare.