Crizotinib, a first-in-class ALK tyrosine kinase inhibitor (TKI) [1], and all the other ALK TKIs such as certinib [2], alectinib [3], lorlatinib [4] and brigatinib [5] have shown significant effects in improving both progression-free survival and overall survival in patients with ALK positive lung cancer in the past decade. This evidence concerns the gene ALK and lung cancer.