Prevalence and breakdown of non-small cell lung cancer BRAF driver mutations in a large UK cohort

Guan Hui Tricia Lim1, Kevin Jon Balbi2, Benjamin Poskitt2

  • 1Department of Cancer Biology, University College London Cancer Institute, London, UK.

Insights

BRAF mutations occur in 3.44% of non-small cell lung cancer (NSCLC) patients in the UK. This study details BRAF mutation classes and co-occurring mutations, aiding targeted therapy selection for NSCLC patients.

Area of Science:

  • Oncology
  • Genetics
  • Molecular Diagnostics

Background:

  • BRAF inhibitors show promise for non-small cell lung cancer (NSCLC) patients with specific BRAF mutations.
  • Understanding BRAF mutation prevalence is crucial for effective therapeutic strategies, as mutation rates vary globally.
  • Previous studies have not comprehensively profiled BRAF mutations in routine UK clinical practice.

Purpose of the Study:

  • To determine the frequency and types of BRAF mutations in a UK NSCLC patient cohort.
  • To analyze the distribution of BRAF mutation classes (I, II, III) and specific mutations like V600E.
  • To investigate the co-occurrence of other oncogenic driver mutations in BRAF-mutated NSCLC.

Main Methods:

  • Analysis of next-generation sequencing (NGS) data from 5384 NSCLC patient biopsies collected over 7 years (2015-2022) in the UK.
  • Identification of BRAF mutations and other driver mutations using amplicon/ion-torrent based NGS assays.
  • Data retrieval included mutation details, classes, and demographic information.

Main Results:

  • BRAF mutations were identified in 185 (3.44%) of 5384 NSCLC cases.
  • Mutation classes included Class I (39.5%), Class II (33.0%), and Class III (27.6%).
  • V600E was the most common Class I mutation (37.3% of all BRAF mutations). KRAS (9.73%) and PIK3CA (3.78%) were the most frequent co-occurring mutations.

Conclusions:

  • This study provides the first large UK cohort analysis of BRAF-positive NSCLC using routine NGS.
  • It establishes the proportion of NSCLC patients likely to benefit from BRAF inhibitors.
  • Highlights the importance of NGS for accurate diagnosis and stratification of NSCLC patients for targeted therapies.