A novel preoperative risk score to optimize patient selection for performing concomitant liver resection with cytoreductive surgery/HIPEC.

Abstract

37 Background: While parenchymal hepatic metastases were previously considered a contraindication to cytoreductive surgery(CRS) and heated intraperitoneal chemotherapy(HIPEC), liver resection(LR) is increasingly performed concomitantly with CRS/HIPEC. As this practice continues to expand, identification of preoperative factors associated with poor outcomes is paramount. Methods: Patients from the US HIPEC Collaborative(2000-2017) with invasive appendiceal or colorectal adenocarcinoma undergoing primary, curative intent CRS/HIPEC with CC0-1 resection were included. LR was defined as a formal parenchymal resection. Primary endpoints were postoperative complications and overall survival(OS). Results: 658 patients were included. Average age was 54 years and 45% were male; 83 (15%) underwent liver resection of colorectal (58%) or invasive appendiceal (42%) metastases. Liver resection patients had more complications (81 vs 60%; p = 0.001), greater number of complications (2.3 vs 1.5; p < 0.001), and required more reoperations (22 vs 11%; p = 0.007) and readmissions (39 vs 25%; p = 0.014) than non-liver resection patients. Liver resection patients had decreased OS (2-year OS 62% vs 79%, p < 0.001), which persisted on multivariable Cox regression when accounting for PCI and histology type. Preoperative factors associated with decreased OS on multivariable analysis in patients undergoing liver resection included age < 60 years (HR:3.61), colorectal histology (HR:3.84), and multiple liver tumors (HR:3.45) (all p < 0.05). When assigning one point for each factor, there was an incremental decrease in 2-yr survival as the risk score increased from 0 to 3 (0: 100%; 1: 91%; 2: 58%; 3: 0%; p < 0.001). Conclusions: As concurrent liver resection with CRS/HIPEC has become more common, we created a simple risk score to stratify patients considered for CRS/HIPEC with liver resection. These data aid in striking the balance between an increased perioperative complication profile with the potential for improvement in overall survival.