PIK3CA and squamous cell carcinoma: In adenocarcinoma, the major contributors encompass EGFR, KRAS, TP53, LRP1B, CDKN2A, EML4-ALK, MET, ROS1, RET, and BRAF, while in squamous cell carcinoma, they encompass TP53, EGFR, LRP1B, NFE2L2, CDKN2A, FAT4, PIK3CA, KMT2C, KRAS, and PTEN [9].