Lung neuroendocrine tumours represent a group of heterogeneous malignancies, and according to the 5th edition of WHO, apparent differences exist between NET and NEC for NETs lack mutations in TP53, RB1, KRAS, and STK11/KEAP1, while, in 40% of cases they have mutations in chromatin-remodelling genes [13]. The gene discussed is KRAS; the disease is neuroendocrine carcinoma.