It has also been used as a second-line therapy for advanced metastatic or recurring non-small cell lung cancer of adenocarcinoma histology [31] due to its strong inhibitory effects on both nonreceptor tyrosine kinases and receptor tyrosine kinases that are involved in the signaling pathways of PDGFR, FGFR, and VEGFR [20,22,23,24,25,26]. Here, NTRK1 is linked to adenocarcinoma.