ERBB2 and small cell lung carcinoma: C797S mutation in the same allele with the T790M mutationEGFR L792F/H/Y, G796S/R, L718Q, L798I, L692V and E709K mutations, and exon 20 insertionLoss of T790M mutationOncogenic gene fusionsMET, FGFR1, EGFR, ERBB2, MAPK1 amplificationHGF, EGF overexpressionIGFR upregulationPIK3CA, BRAF, KRAS, CDKN2A, ALK, KIT, RB1 mutationsHistologic transformation (EMT and SCLC)