Dataset Information

Co-occurring Genomic Alterations and Association With Progression-Free Survival in BRAFV600-Mutated Nonmelanoma Tumors.

ABSTRACT: BRAFV600 mutations occur in multiple nonmelanoma tumors, but no US Food and Drug Administration-approved BRAF-targeted therapies exist for these cancers. BRAF inhibitor vemurafenib was recently found to demonstrate activity across various BRAF-mutated nonmelanoma cancer types. However, most tumors ultimately become resistant to BRAF-targeted monotherapy. To identify whether co-occurring genomic alterations drive resistance to BRAF-targeted therapies, we analyzed next-generation sequencing data from 30 advanced BRAF-mutated nonmelanoma cancers treated with BRAF inhibitor monotherapy. Kaplan-Meier survival analysis and Cox proportional hazard regression analysis were performed and hazard ratios (HR) with 95% confidence intervals (CI) were calculated. All statistical tests were two-sided. We identified a strong association between co-occurring PI3K-mTOR pathway aberrations and primary resistance to BRAF-targeted therapy. PI3K-mTOR pathway aberrations were associated with a statistically significant reduction in progression-free survival (HR = 15.0, 95% CI = 3.6 to 63.0, P < .001) and overall survival (HR?=?19.2, 95% CI?=?3.7 to 100.0, P < .001). This suggests that co-occurring genomic alterations may predict response and resistance to BRAF inhibitor therapy and identify subgroups of BRAF-mutated nonmelanomas cancers.

SUBMITTER: Sen S

PROVIDER: S-EPMC6059192 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Co-occurring Genomic Alterations and Association With Progression-Free Survival in BRAFV600-Mutated Nonmelanoma Tumors.

Sen Shiraj S Meric-Bernstam Funda F Hong David S DS Hess Kenneth R KR Subbiah Vivek V

Journal of the National Cancer Institute 20171001 10

BRAFV600 mutations occur in multiple nonmelanoma tumors, but no US Food and Drug Administration-approved BRAF-targeted therapies exist for these cancers. BRAF inhibitor vemurafenib was recently found to demonstrate activity across various BRAF-mutated nonmelanoma cancer types. However, most tumors ultimately become resistant to BRAF-targeted monotherapy. To identify whether co-occurring genomic alterations drive resistance to BRAF-targeted therapies, we analyzed next-generation sequencing data f ...[more]

PMID: 29117359

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Project description:IntroductionEGFR exon 20 insertions (EGFRex20ins) comprise an uncommon subset of EGFR-activating alterations relatively insensitive to first- and second-generation EGFR tyrosine kinase inhibitors (TKIs). However, recent early clinical data suggests these patients may benefit from newer-generation EGFR-TKIs. Comprehensive genomic profiling (CGP) identifies a broad spectrum of EGFRex20ins and associated co-occurring genomic alterations (GAs) present in NSCLC.MethodsHybrid capture-based CGP was performed prospectively on 14,483 clinically annotated consecutive NSCLC specimens to a mean coverage depth of greater than 650X for 236 or 315 cancer-related genes.ResultsOf 14,483 NSCLC cases, CGP identified 263 (1.8%) cases with EGFRex20ins, representing 12% (263 of 2251) of cases with EGFR mutations. Sixty-four unique EGFRex20ins were identified, most commonly D770_N771>ASVDN (21%) and N771_P772>SVDNP (20%). EGFR amplification occurred in 22% (57 of 263). The most common co-occurring GAs effected tumor protein p53 (TP53) (56%), cyclin dependent kinase inhibitor 2A (CDKN2A) (22%), cyclin dependent kinase inhibitor 2B (CDKN2B) (16%), NK2 homeobox 1 (NKX2-1) (14%) and RB transcriptional corepressor 1 (RB1) (11%); co-occurring GAs in other known lung cancer drivers were rare (5%). Average tumor mutational burden was low (mean 4.3, range 0 to 40.3 mutations/Mb). Clinical outcomes to first- and second-generation EGFR TKIs were obtained for five patients and none responded.ConclusionsIn the largest series of EGFRex20ins NSCLC, diverse EGFRex20ins were detected in 12% of EGFR-mutant NSCLC, a higher frequency than previously reported in smaller single-institution studies. Clinical outcomes showed lack of response to EGFR TKIs. Tumor mutational burden was low, consistent with non-smoking associated NSCLC. Comprehensive sequencing revealed increased proportion and wide variety of EGFRex20ins, representing a population of patients significant enough for focused efforts on effective interventions.

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Dataset Information

Co-occurring Genomic Alterations and Association With Progression-Free Survival in BRAFV600-Mutated Nonmelanoma Tumors.

Publications

Co-occurring Genomic Alterations and Association With Progression-Free Survival in BRAFV600-Mutated Nonmelanoma Tumors.

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