EGFR and neoplasm: Osimertinib is a potent, irreversible oral TKI that selectively targets both sensitizing EGFR mutations (EGFRms) and the T790M resistance mutation, with approval for monotherapy as a form of adjuvant treatment after complete tumor resection in adult patients with stage IB-IIIA NSCLC whose tumors present deletions in exon 19 of EGFR or exon 21 (L858R) substitution mutations.