The effect of neuraxial anesthesia on cancer recurrence and survival after cancer surgery: an updated meta-analysis

Several animal and observational studies have evaluated the effects of neuraxial anesthesia on the recurrence and survival of cancer surgery; studies reported benefit, whereas others did not. To provide further evidence that neuraxial anesthesia(combined with or without general anesthesia (GA)) may be associated with reduced cancer recurrence and long-term survival after cancer surgery, we conducted this meta-analysis. A total of 21 studies were identified and analyzed, based on searches conducted using PubMed, Web of Science, EMBASE database and the Cochrane Database of Systematic Reviews. After data abstraction, adjusted hazard ratios (HR) with 95% confidence intervals (CIs) were used to assess the impact of neuraxial anesthesia (combined with or without GA) and GA on oncological outcomes after cancer surgery. For overall survival (OS), a potential association between neuraxial anesthesia and improved OS (HR 0.853, CI 0.741-0.981, P = 0.026, the random-effects model) was observed compared with GA. Specifically, we found a positive association between neuraxial anesthesia and improved OS in colorectal cancer (HR 0.653, CI 0.430-0.991, P = 0.045, the random-effects model). For recurrence-free survival (RFS), a significant association between neuraxial anesthesia and improved RFS (HR 0.846, CI 0.718-0.998, P = 0.047, the random-effects model) was detected compared with GA. Our meta-analysis suggests that neuraxial anesthesia may be associated with improved OS in patients with cancer surgery, especially for those patients with colorectal cancer. It also supports a potential association between neuraxial anesthesia and a reduced risk of cancer recurrence. More prospective studies are needed to elucidate whether the association between neuraxial use and survival is causative.