In our study, 15 (35.7%) of the 42 ALK IHC-positive patients had solid predominant with mucin production adenocarcinoma, and analysis of clinicopathologic characteristics showed that ALK rearrangement was significantly more common in patients with solid predominant with mucin production adenocarcinoma than in patients with other subtypes (P = 0.006). The gene discussed is MUC5AC; the disease is adenocarcinoma.