IL6 and cancer: We observed significant heterogeneity in the analysis of the IL-6 rs1800795 (-174G /C) polymorphism for overall cancer [CC vs.GG: Q = 258.44, df = 97, p-value = 0.0001,τ2 = 0.0747, I2 = 62.47%; CC vs. CG + GG: Q = 228.48, df = 97, p-value = 97, τ2 = .0478, I2 = 57.53%; CC + CG vs. GG: Q = 333.19, df = 100, p-value = 0.0001, τ2 = .0485, I2 = 69.98%; CG vs. CC + GG: Q = 297.07, df = 100, p-value = 0.0001, τ2 = .0385, I2 = 66.34%; C vs. G: Q = 378.15, df = 100, p-value = 0.0001, τ2 = .0290, I2 = 73.56%].