EGFR and non-small cell lung carcinoma: Defining profile 1 and profile 2 exon 19 variants as having β3/αC loop deletions of ≤3 or ≥4 residues respectively, we analyzed de-identified outcome data from the GENIE+ database54 for patients with a diagnosis of non-small cell lung cancer whose tumors harbored an EGFR exon 19 mutation and were treated with erlotinib.