NTRK2 and non-small cell lung carcinoma: Alterations of the neurotrophic tyrosine kinase (NTRK) genes (i.e., NTRK1, NTRK2, and NTRK3) are rare in NSCLC, representing less than 1% (about 0.1–0.6%) of the NSCLC population [5,58,59].