Subgroup analysis showed that STAT3 expression was associated with worse 5-year OS of gastric cancer (OR = 5.48, 95% CI = 2.14 to 14.01, P = 0.0004), hepatic cancer (OR = 2.48, 95% CI = 1.41 to 4.35, P = 0.002), osteosarcoma (OR = 4.84, 95% CI = 2.23 to 10.50, P < 0.0001), pancreatic cancer (OR = 9.71, 95% CI = 1.80 to 52.41, P = 0.008) and prostate cancer (OR = 8.35, 95% CI = 1.81 to38.51, P = 0.007) (Figure 5). This evidence concerns the gene STAT3 and gastric cancer.