TM4SF18 and gastric cancer: Univariate Cox regression analysis showed that factors affecting survival in GC included age (P = 0.006, HR = 1.027), gender (P = 0.062, HR = 1.484), grade stage (P = 0.095, HR = 1.368), stage (P < 0.001, HR = 1.535), T‐stage (P = 0.032, HR = 1.298), M‐stage (P = 0.025, HR = 2.048), N‐stage (P = 0.006, HR = 1.267), and TM4SF18 expression levels (P = 0.032, HR = 1.295) (Fig. 4A, Table 3).