Impact of KEAP1/NFE2L2/CUL3 mutations on duration of response to EGFR tyrosine kinase inhibitors in EGFR mutated non-small cell lung cancer

Objectives: For patients with Epidermal Growth Factor Receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), frontline EGFR-tyrosine kinase inhibitor (TKI) therapy compared to chemotherapy improves outcomes. However, resistance to these agents uniformly develops. Recently, mutations in the KEAP1-NFE2L2 pathway have been implicated as a potential mechanism of acquired EGFR TKI resistance. Materials and methods: We examined all patients with metastatic NSCLC with mutations in both EGFR and KEAP1/NFE2L2/CUL3 identified on next generation sequencing from 2015 - 2018. These patients were compared to a NSCLC control cohort with mutations in EGFR and wild type in KEAP1/NFE2L2/CUL3 matched on the basis of sex, smoking status, age and race. Time to treatment failure on EGFR TKI therapy and overall survival were examined. Results: Among 228 EGFR mutant NSCLCs, 17 (7%) also carried mutations in KEAP1, NFE2L2, or CUL3. The most common co-mutation in both the KEAP1/NFE2L2/CUL3 mutant and wild-type cohort was TP53. Patients with KEAP1/NFE2L2/CUL3 mutations had a shorter median time to treatment failure on EGFR TKI (4.7 months) compared with the wild-type matched cohort (13.0 months), p= 0.0014. There was no difference in overall survival. Conclusion: For NSCLC patients with mutations in EGFR, co-mutations in KEAP1/NFE2L2/CUL3 are associated with significantly decreased time to treatment failure. Our results suggest that these mutations represent a mechanism of intrinsic resistance to TKI treatment.