The cancer surgery only subgroup analysis included seven studies, and the IL-6 level was significantly lower in EA cohort (SMD = −1.75, 95% CI = −2.61 to −0.9, I2 = 93%, Egger’s regression p = 0.01, trim and fill reported no missing studies, Supplementary Figure S4B) [23,24,27,28,35,39,41,42]. This evidence concerns the gene IL6 and cancer.