Epidermal growth factor receptor (EGFR) sensitizing mutations (EGFR)

The Epidermal Growth Factor Receptor (EGFR) sensitizing mutations refer to specific genetic alterations, primarily exon 19 deletions and the L858R point mutation, that result in the constitutive activation of the EGFR signaling pathway [PubMed: 15070794]. These mutations are predominantly found in non-small cell lung cancer (NSCLC) and drive oncogenesis by promoting cell proliferation and inhibiting apoptosis through the MAPK and PI3K/Akt pathways [Nature Reviews Cancer, 2007]. The term sensitizing reflects the increased susceptibility of these mutant forms to tyrosine kinase inhibitors (TKIs) compared to the wild-type receptor [NEJM: 350(21)]. Clinical use of TKIs like erlotinib, afatinib, and osimertinib has revolutionized the treatment of EGFR-mutant NSCLC, providing significant progression-free survival benefits [FDA, 2018]. Despite initial high response rates, patients typically develop acquired resistance through secondary mutations like T790M or C797S, which alter the binding affinity of the drugs [Cancer Discovery, 2011]. Monitoring for these mutations via liquid or tissue biopsy is a standard part of modern precision oncology [NCCN Guidelines].

Other names

EGFR activating mutationsEGFR exon 19 deletionsEGFR L858R mutationEGFR-mutantEGFR kinase domain mutations

Tyrosine kinase inhibition via competitive binding to the ATP-binding site of the mutated EGFR kinase domain, thereby blocking downstream signaling pathways [StatPearls: NBK541091].