Can Peritoneal Cancer Index be Determined in 18F-FDG PET/CT Before Surgery in Ovarian Peritoneal Carcinomatosis?

Background: This study aimed to evaluate the accuracy and reliability of preoperative 18F-FDG PET/CT in predicting the peritoneal cancer index (PCI) in patients diagnosed with peritoneal carcinomatosis secondary to ovarian cancer. Methods: Thirty patients with ovarian cancer (FIGO stages IIIC to IV) who underwent preoperative 18F-FDG PET/CT imaging at our institution were included. The surgical peritoneal cancer index (sPCI) was statistically compared with the radiological PCI (rPCI) derived from preoperative 18F-FDG PET/CT scans. Results: Statistical analysis revealed significantly lower predictive values for rPCI compared to sPCI (p = 0.013). Subgroup analysis demonstrated no statistically significant difference between sPCI and rPCI in patients with sPCI ≤ 10 (p = 0.096). Conclusions: Our findings suggest that 18F-FDG PET/CT has limited utility in predicting the peritoneal cancer index in ovarian carcinomatosis. However, it may be clinically reliable in cases where the radiological PCI is < 10.