Regional anesthesia might reduce recurrence and metastasis rates in adult patients with cancers after surgery: a meta-analysis.

Background: The influence of anesthesia techniques on cancer recurrence and metastasis following oncological surgery is a topic of growing interest. This meta-analysis investigates the potential effects of regional anesthesia (RA), either independently or combined with general anesthesia (GA), on these outcomes.

Methods: We performed an extensive search across PubMed, Embase, and the Cochrane Library databases. The primary outcome was cancer recurrence, while the secondary outcomes were local recurrence and distant metastasis. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated by utilizing random-effects models. The Newcastle-Ottawa Scale (NOS) was used for quality assessment of observational studies, the Cochrane Risk of Bias Tool for Randomized Trials (Rob 2.0) was used for randomized controlled trials, and all the outcomes were assessed by using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE).

Results: This study included 32 studies comprising 24,724 cancer patients. RA, either alone or in combination with GA, was significantly associated with reduced cancer recurrence compared to GA alone (OR = 0.82; 95% CI = 0.72 to 0.94; p < 0.01). This association remained significant for prostate cancer patients in subgroup analyses (OR = 0.71; 95% CI = 0.51 to 0.98; p = 0.04) and in the context of epidural anesthesia combined with GA. However, there were no significant associations noted for local recurrence or distant metastasis.

Conclusions: This meta-analysis provides evidence that RA, used alone or adjunctively with GA, is associated with a lower risk of cancer recurrence, particularly in patients with prostate cancer. However, no significant effects were observed on local recurrence or distant metastasis. Further prospective studies should be conducted to clarify this important issue.