Validation of clinical risk score for colorectal liver metastases resected in a contemporary multicenter cohort.

ABSTRACT

BACKGROUND: Recent advances in care for colorectal liver metastases (CRLM) have lengthened 5-year survival. In this new era, prognostic tools such as the clinical risk score (CRS) for colorectal liver metastases require reevaluation. METHODS: Patients undergoing resection for CRLM between 2008 and 2012 at 4 specialty hepatobiliary centers in Canada (N = 740) were stratified by CRS and analyzed in Kaplan-Meier survival curves. Primary outcome of overall survival (OS) and secondary outcome of recurrence-free survival (RFS). Multivariate Cox regression compared CRS to patient factors. RESULTS: Median OS not reached (>60 months), median RFS 16 months. Original CRS strata was a significant (p < 0.001) predictor of both OS (5-year OS 0; 75%, 1; 71%, 2; 57%, 3; 57%, 4; 46%) and RFS (5-year RFS 0; 39%, 1; 33%, 2; 21%, 3; 21%, 4; 8%). The presence of extrahepatic colorectal metastatic disease increased recurrence risk (RFS hazard ratio of 1.32 (1.06-1.65)), and the use of intraoperative portal pedicle clamping reduced recurrence risk (RFS hazard ratio of 0.78 (0.61-0.99)). CONCLUSIONS: The CRS remains a relevant tool for predicting long-term outcomes for patients undergoing resection of CRLM. Additional factors such as the presence of extrahepatic colorectal metastatic disease and the use of intraoperative portal pedicle clamping may improve the prognostic power of the CRS.