ALK and anaplastic large cell lymphoma: Sections of healthy colon tissue (Maixin Bio, Fuzhou, China) served as the positive controls for the expression of vimentin, SMA, desmin, AE1/AE3, S-100, DOG1, CD34 and CD117, and an ALK-positive anaplastic large cell lymphoma cell line (Maixin Bio) served as the positive control for ALK staining.