TB is the gold standard approach for diagnosis of NSCLC and histological subtype identification, as well as for some predictive biomarker assessment using IHC (such as immunostaining for PD-L1 and ALK), FISH (ALK, ROS1, and MET), and molecular biology testing (one gene sequencing and NGS methods). The gene discussed is ALK; the disease is non-small cell lung carcinoma.