KRAS and squamous cell carcinoma: Of the 13 patients with compound mutations, 4 had G719X plus Ser768Ile (S768I), 4 had de novo T790 M plus either Leu858Arg (L858R) or deletion(del)19, 2 had L858R plus del19, 1 had L858R plus Ex20Ins, 1 had del19 plus KRAS mutation in treatment-naïve, and 1 with Gly719Xaa plus E709A was found in squamous cell carcinoma.