RB1 and squamous cell carcinoma: While certain alterations (e.g., RB1, MYCL1) resemble patterns found in SCLC4–6,23, others are typical of lung adenocarcinoma or squamous cell carcinomas (e.g., STK11, KEAP1, NKX2-1, RAS, BRAF, and NFE2L2)1–3,7,21.