ALK and cancer: Later on, other gatekeeper mutations (Table 2), such as ALK‐L1196M, ROS1‐L2026M, FGFR1‐V561F/M, FGFR2‐V564F/I, FGFR3‐V555E, FGFR4‐V550L/E/M, RET‐V804L/M, FLT3‐F691I/L, KIT ‐T670I, and PDGFRα‐T674I, were identified in patients with IGST, NSCLC, or other cancers after corresponding TKI treatment.59