Particularly, Rekhtman et al. have carefully assessed the occurrence of EGFR and KRAS mutations in LSQCC and have observed that mutations of both these genes were absent in typical cases of LSQCC; rare cases positive for EGFR or KRAS mutations can be identified as rare mixed squamous-adenocarcinomas [33]. The gene discussed is KRAS; the disease is adenocarcinoma.