ALK and lung adenocarcinoma: When only lung adenocarcinomas was concerned, NSCLC patients with stage I–III had lower yet nonsignificant incidence of ALK rearrangements than those with stage IV (OR = 0.53; 95% CI: 0.25–1.09; P = 0.09), with moderate heterogeneity (I2 = 52%) and evident publication bias (Nfs = −1.14) (Figure S6).