IHC was used to detect the expression of EML4-ALK in tissue samples of 2631 patients with NSCLC; 187 cases were positive (Figure 1), the positive rate was 7.11% (187/2631), and the positive rate in adenocarcinoma was 9.51% (170/1787) and 2.01% (17/844) in squamous cell carcinoma. Here, EML4 is linked to squamous cell carcinoma.