The resistance mechanisms of T790M-negative tumors include the amplification of MET or HER2, the epithelial-to-mesenchymal transition (EMT), phenotype change to small-cell lung cancer (SCLC), and point mutations in B-RAF, KRAS, TP53, and PIK3CA (for review, [17]). This evidence concerns the gene ERBB2 and small cell lung carcinoma.