The effect of metastasis location on outcome after cytoreductive surgery and heated intraperitoneal chemotherapy

Objectives: This study aims to evaluate how metastases in the seven topographical regions of the simplified peritoneal cancer index (sPCI) affect the survival of patients treated with cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis (PC) from colorectal (CRC) or appendiceal cancers. Methods: Data was collected retrospectively from patient records. Abdominal regions affected by PC were identified using the histological verification of surgically removed tumours found in the electronic pathology report. Verified tumours were grouped according to the sPCI topography. Results: One hundred and eighty-three patients treated with CRS and HIPEC were included. Metastases in the small bowel had a negative impact on survival with a hazard ratio of 1.89 (p=0.005). A significantly impaired survival was also detected for patients affected by metastases in the ileocolic region (p=0.01) and in the omentum and spleen (p =0 .04). Conclusions: When selecting patients for CRS and HIPEC a more cautious approach may be applied by considering the regions affected.