CDKN2A and large cell neuroendocrine carcinoma: Commonly altered genes in these LCNEC tumors included TP53 (75%), RB1 (32.1%), SMARCA4 (21.4%), NOTCH1 (17.9%), KEAP1 (17.9%) with few cases of KRAS, EGFR, and CDKN2A mutations and STK11 mutation or loss (see Figure 1).