PIK3CA and neuroendocrine carcinoma: Among lung cancers, for example, alterations in EGFR, KRAS, SMARCA4, STK11, and KEAP1 are almost exclusively observed in LUADs24; LUSCs often carry mutations in TP53, CDKN2A, RB1, NFE2L2, KEAP1, PIK3CA, and PTEN25, while RB1 and TP53 are frequently altered in neuroendocrine carcinomas (NEC) including LCNEC and SCLC26.