Positive Impact of Epidural Analgesia on Oncologic Outcomes in Patients Undergoing Resection of Colorectal Liver Metastases

Introduction. Previous studies have suggested that the use of regional anesthesia can reduce recurrence risk after oncologic surgery. The purpose of this study was to assess the effect of epidural anesthesia on recurrence-free (RFS) and overall survival (OS) after hepatic resection for colorectal liver metastases (CLM). Methods. After approval of the institutional review board, the records of all adult patients who underwent elective hepatic resection between January 2006 and October 2011 were retrospectively reviewed. Patients were categorized according to use of perioperative epidural analgesia versus intravenous analgesia. Univariate and multivariate analyses were performed to identify factors influencing RFS and OS. Results. Of 510 total patients, 390 received epidural analgesia (EA group) and 120 patients received intravenous analgesia (IVA group). Compared with the IVA group, more patients in the EA group underwent associated surgical procedures with consequently longer operative times (p < 0.001). In addition, the EA group received more intraoperative fluids and had higher urine output volumes (p <= 0.001). Five-year RFS was longer in the EA group (34.7 %) compared with the IVA group (21.1 %). On multivariate analysis, the receipt of epidural analgesia was an independent predictor of improved RFS (p = 0.036, hazard ratio [HR] 0.74; 95 % confidence interval [CI] 0.56-0.95), but not OS (p = 0.102, HR 0.72; 95 % CI 0.49-1.07). Conclusions. This study suggests an association between epidural analgesia and improved RFS, but not OS, after CLM resection. These results warrant further prospective, randomized studies on the benefits of regional anesthesia on oncologic outcomes after hepatic resection for CLM.