Genomic Profiling Identifies Outcome-Relevant Mechanisms of Innate and Acquired Resistance to Third-Generation Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Therapy in Lung Cancer.
retrospective_cohort · Level III
Where this comes from
- Record sourced from PubMed, PMID 32914023.
- Also identified by DOI 10.1200/PO.18.00210 and PMC identifier 7446436.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Third-generation epidermal growth factor receptor (<i>EGFR</i>) tyrosine kinase inhibitors (TKIs) are effective in acquired resistance (AR) to early-generation EGFR TKIs in EGFR-mutant lung cancer. However, efficacy is marked by interindividual heterogeneity. We present the molecular profiles of pretreatment and post-treatment samples from patients treated with third-generation EGFR TKIs and their impact on treatment outcomes. Using the databases of two lung cancer networks and two lung cancer centers, we molecularly characterized 124 patients with <i>EGFR</i> p.T790M-positive AR to early-generation EGFR TKIs. In 56 patients, correlative analyses of third-generation EGFR TKI treatment outcomes and molecular characteristics were feasible. In addition, matched post-treatment biopsy samples were collected for 29 patients with progression to third-generation EGFR TKIs. Co-occurring genetic aberrations were found in 74.4% of <i>EGFR</i> p.T790-positive samples (n = 124). Mutations in <i>TP53</i> were the most frequent aberrations detected (44.5%; n = 53) and had no significant impact on third-generation EGFR TKI treatment. Mesenchymal-epithelial transition factor (<i>MET</i>) amplifications were found in 5% of samples (n = 6) and reduced efficacy of third-generation EGFR TKIs significantly (eg, median progression-free survival, 1.0 months; 95% CI, 0.37 to 1.72 <i>v</i> 8.2 months; 95% CI, 1.69 to 14.77 months; <i>P</i> ≤ .001). Genetic changes in the 29 samples with AR to third-generation EGFR TKIs were found in <i>EGFR</i> (eg, p.T790M loss, acquisition of p.C797S or p.G724S) or in other genes (eg, <i>MET</i> amplification, <i>KRAS</i> mutations). Additional genetic aberrations are frequent in EGFR-mutant lung cancer and may mediate innate and AR to third-generation EGFR TKIs. <i>MET</i> amplification was strongly associated with primary treatment failure and was a common mechanism of AR to third-generation EGFR TKIs. Thus, combining EGFR inhibitors with TKIs targeting common mechanisms of resistance may delay AR.