Peritoneal carcinomatosis index predicts survival in colorectal patients undergoing HIPEC using oxaliplatin: a retrospective single-arm cohort study

Background: Peritoneal carcinomatosis (PC) from colorectal cancer is associated with poor prognosis. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) has improved survival for patients with colorectal peritoneal carcinomatosis. However, standardization of HIPEC protocols, including which chemotherapeutic agent to use, is lacking in the literature. Therefore, we sought to report survival outcomes from colorectal cancer patients undergoing CRS/oxaliplatin-based HIPEC at our institution over the last 10 years. Methods: Colorectal PC patients treated with CRS/oxaliplatin-based HIPEC 2004-2015 were included. Demographic, clinical, and oncologic data were abstracted from the medical record. Overall (OS) and disease-free survival (DFS) were calculated using Kaplan-Meier analysis. Univariate/multivariate Cox regression analysis was done. Results: Laparotomy was performed in 113 patients for colorectal PC; 91 completed a curative intent CRS/HIPEC. At 3 and 5 years, OS for the CRS/HIPEC cohort was 75% and 55%, and DFS was 50% and 25%, respectively. On multivariate analysis, incremental increases in peritoneal carcinomatosis index (PCI) were associated with worse OS (p = 0.0001) and DFS (p = 0.0001). Grade III/IV complications were also associated with worse OS. Conclusions: A standardized regimen of CRS and oxaliplatin-based HIPEC for colorectal PC is effective with favorable OS and DFS and acceptable complication rates.