Introduction PCI is widely used to evaluate peritoneal carcinomatosis. This study aims to assess the correlation between preoperative and intraoperative PCI. The secondary objectives were determining whether PCI could predict surgical oncologic outcomes and overall survival.

Methods In a retrospective cohort study, women with advanced-stage epithelial ovarian cancer, primary peritoneal cancer, or fallopian tube cancer who underwent primary cytoreductive surgery or interval debulking were included. The preoperative CT scan findings and intraoperative measurement of the peritoneal carcinomatosis were evaluated using PCI, and their correlation was determined using the Spearman coefficient. The overall survival was calculated using the Kaplan-Meier method.

Results 55 women were enrolled, and 52 patients were eligible and analyzed. Mean preoperative and intraoperative PCI were 5.04 and 7.27, orderly. Twenty-nine patients achieved optimal surgery (55.8%). A moderate correlation exists between the PCI obtained from the CT image and surgical findings (r= 0.510, P< 0.001). The significant cutoff values of preoperative PCI and intraoperative PCI to predict optimal surgical outcomes could be 7 and 8, respectively. In multivariate analysis, preoperative CA125 < 416 U/mL and intraoperative PCI < 8 were the only independent factors for optimal surgery. The overall survival was significantly improved in patients with an intraoperative PCI score of less than 8(14 to 36 months, p=0.015).

Conclusion/Implications The lesser PCI that would predict the optimal surgical outcome, the preoperative PCI from practical imaging would be beneficial as a predictive method to assess the possibility of optimal cytoreduction and the optimal time for surgery.