ALK and squamous cell lung carcinoma: In lung squamous cell carcinoma, the mutation rate of EGFR (12 out of 310, 3.9%), KRAS (8 out of 310, 2.6%), HER2 (1 out of 310, 0.3%), BRAF (1 out of 310, 0.3%), ALK (2 out of 310, 0.6%), DDR2 (1 out of 310, 0.3%), AKT1 (1 out of 310, 0.3%), FGFR1 fusions (2 out of 312, 0.6%) and FGFR3 fusions (9 out of 312, 2.9%) has been reported in our previous studies [8, 9].