RESUMO
Purpose: The third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), osimertinib, is an effective first-line therapy for patients with common EGFR mutation-positive non-small cell lung cancer (NSCLC). However, almost all patients become resistant to treatment. In some patients, emergence of tertiary EGFR mutations is implicated as a resistance mechanism. This study describes patients with NSCLC who acquired the rare EGFR mutations, L718Q or G724S, following EGFR TKI treatment. Patients and Methods: This was a retrospective, observational study undertaken in France from Feb-Nov 2021, in patients with EGFR mutation-positive NSCLC with an acquired L718Q or G724S mutation. Primary objectives were description of tumor characteristics, progression, and progression under treatment. Results: Nine eligible patients were identified. Acquired resistance to initial EGFR TKI treatment was associated with T790M emergence in six patients, who then received osimertinib monotherapy. Overall, eight patients received osimertinib monotherapy treatment at some point (average treatment duration: 18.3 months). Following the emergence of L718Q or G724S, patients received chemotherapy (n = 4; two of whom subsequently received afatinib), nivolumab (n = 2), afatinib (n = 2), or immunochemotherapy (n = 1). In the four patients who received afatinib after identification of L718Q or G724S, 2 achieved a partial response, one had stable disease and one had progressive disease. Treatment duration was 1.6-31.7 months. In patients with controlled disease (n = 3), progression-free survival was 6.1-31.7 months. Two of these patients had previously received osimertinib. Conclusion: Currently, there is no consensus regarding the treatment of EGFR mutation-positive NSCLC following emergence of the osimertinib resistance mutations, L718Q or G724S. Afatinib appears to be a promising treatment option in this setting.
RESUMO
Background: Few epidemiological data are available on surgically treated Caucasian patients with non-small-cell lung cancers (NSCLCs) harboring epidermal growth factor receptor (EGFR) mutations. The main objective of this study was to describe, in the real-world setting, these patients' incidence, clinical, and tumoral characteristics. Methods: The participating centers included all consecutive localized non-squamous NSCLC patients undergoing surgery between January 2018 and December 2019 in France. EGFR status was determined retrospectively when not available before surgery. Results: The study includes 1391 no squamous NSCLC patients from 16 centers; EGFR status was determined before surgery in 692 (49.7%) of the cases and conducted as part of the study for 699 (50.3%); 171 (12.3%) were EGFR mutated; median age: 70 (range: 36-88) years; female: 59.6%; never smokers: 75.7%; non-squamous histology 97.7%, programmed death ligand-1 expression 0%/1-49%/⩾50 in 60.5%/25.7%/13.8%, respectively. Surgery was predominantly lobectomy (81%) or segmentectomy (14.9%), with systematic lymph node dissection in 95.9%. Resection completeness was R0 for 97%. Post-surgery staging was as follows: IA: 52%, IB: 16%, IIA: 4%, IIB: 10%, IIIA: 16%, and IIIB: 0.05%; EGFR mutation exon was Del19/exon 21 (L858R)/20/18 in 37.4%/36.8%/14%, and 6.4% of cases, respectively; 31 (18%) patients received adjuvant treatment (chemotherapy: 93%, EGFR tyrosine kinase inhibitor: 0%, radiotherapy: 20%). After a median follow-up of 31 (95% confidence interval: 29.6-33.1) months, 45 (26%) patients relapsed: 11/45 (24%) locally and 34 (76%) with metastatic progression. Median disease-free survival (DFS) and overall survival were not reached and 3-year DFS was 60%. Conclusion: This real-world analysis provides the incidence and outcomes of resected EGFR-mutated NSCLCs in a European patient cohort.