Non-Small Cell Lung Carcinoma
Somatic mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) gene are present in approximately 80% of the lung adenocarcinomas that respond to first and second generation EGFR inhibitors (eg, gefitinib, erlotinib and afatinib). Two types of mutations account for approximately 80-90% of all EGFR mutations: short in-frame deletions in Exon 19 and a point mutation in exon 21 at codon 858 (L858R). Other less common mutations in exons 18, 20, and 21 are found in 10-20% of EGFR-mutated cases. EGFR Exon 19 deletions, EGFR Exon 21 L858R and EGFR Exon 18 G719 mutations correlate strongly with sensitivity to specific EGFR inhibitors and the response rate to therapy with TKIs has been reported to be up to 80% in such cases. The T790M mutation in exon 20 is associated with resistance to some EGFR inhibitors. However, third generation TKI (eg, osimertinib) can specifically target T790M. EGFR L747P (c.2239_2240 TT>CC) is a rare missense compound substitution mutation in the Exon 19 and has been reported to be resistant to some EGFR inhibitors.
Pao W, et al. EGF receptor gene mutations are common in lung cancers from "never smokers" and are associated with sensitivity of tumors to gefitinib and erlotinib. Proc Natl Acad Sci U S A 2004;101(36):13306-11
Wu JY, et al. Effectiveness of tyrosine kinase inhibitors on "uncommon" epidermal growth factor receptor mutations of unknown clinical significance in non-small cell lung cancer. Clin Cancer Res 2011;17(11):3812-21
Disclaimer: You assume full responsibility for all risks associated with using this PMKB website. The IPM makes no guarantee of the comprehensiveness, reliability or accuracy of the information on this website and the IPM assumes no responsibility for errors in the information associated with this web site. Healthcare providers and patients must integrate all clinical and laboratory findings as well as information from a variety of sources before deciding on appropriate clinical care options.