Intraoperative Fentanyl Consumption Does Not Impact Cancer Recurrence or Overall Survival after Curative Colorectal Cancer Resection

Whether opioid use in cancer surgery would promote tumor dissemination in humans is inconclusive. We investigated the effect of intraoperative fentanyl dose on colorectal cancer (CRC) prognosis following resection in this retrospective study. A total of 1679 patients with stage I-III CRC undergoing tumor resection between January 2011 and December 2014 were evaluated through August 2016. Postoperative recurrence-free survival (RFS) and overall survival (OS) were analyzed using Cox regression models. Multivariable Cox regression analysis demonstrated no dose-response association between the amount of fentanyl dose and RFS (adjusted hazard ratio: 1.03, 95% CI: 0.89-1.19) or OS (adjusted hazard ratio: 0.84, 95% CI: 0.64-1.09). Patients were further classified into the high- and low-dose groups by the median of fentanyl dose (3.0 μg·kg^-1), and there was no significant difference in RFS or OS between groups, either (adjusted hazard ratio: 0.93, 95% CI: 0.74-1.17 for RFS; 0.79, 95% CI: 0.52-1.19 for OS). We concluded that intraoperative fentanyl consumption has no impact on recurrence-free or overall survival in patients after curative CRC resection.