Introduction/Background Peritoneal carcinomatosis in ovarian cancer is frequent and generally associated with higher stage and poorer outcome. The clinical features of peritoneal carcinomatosis are diverse and their relevance for surgical and long-term outcome remains unclear. We conducted this prospective study to describe intraoperatively the different features of peritoneal carcinomatosis(PC) and to correlate them with clinicopathological features and survival outcomes.

Methodology We performed systematic analysis of all patients with documented intraoperative PC and a primary diagnosis of epithelial ovarian, tubal, or peritoneal cancer from January 2001 to September 2018. All data were evaluated by using the systematic tumour bank tool. Specific PC features included texture(soft-hard), consistency(coarse-fine or both), wet vs dry, and localization(diffuse-local). The PC characteristics were then evaluated for correlation with age, FIGO-stage, tumour histology, lymph-node involvement, tumour grade, and presence of residual tumour. Moreover, the influence of PC characteristics on overall-survival(OS) and progression-free survival (PFS) was analysed.

Results 1686 patients with PC and primary epithelial ovarian cancer were included. Majority of the patients had diffuse PC(73.9%). The majority of PC were fine in texture (55.3%) and hard in consistency (87.4%). 27.6% of patients had dry PC. Diffuse localization of PC was significantly associated with higher FIGO stage(p<0.001), high-grade(p=0.003), serous tumours(p=0.006) and residual tumour as compared to local PC(p<0.001). Wet PC significantly correlated with diffuse localization(p <0.001) and residual tumour as compared to dry PC(p<0.001). Coarse PC was significantly associated with residual tumour as compared to fine PC(p=0.044). Diffuse peritoneal localization(p<0.001), wet PC(p<0.001), and lymph-node involvement(p<0.001) were associated with lower OS and PFS-rates.

Conclusion Diffuse PC was a significant predictor of recurrence. Lower OS and PFS were associated with diffuse PC, wet PC, and additional lymph node involvement. Further prospective trials are warranted with the inclusion of translational research aspects to better understand the different peritoneal carcinomatosis pattern.