BRAF mutation predicts survival after immunotherapy across multiple cancer types

Area of Science:

• Oncology
• Immunotherapy
• Genetics

Background:

• Emerging evidence suggests a correlation between BRAF mutations and positive responses to immune checkpoint inhibitor (ICI) therapy in specific cancers.
• The association between BRAF mutations and ICI therapy benefits needs broader investigation across a wider range of cancer types.

Purpose of the Study:

• To conduct a pan-cancer analysis investigating the association between BRAF mutations and overall survival in patients treated with ICI therapy.
• To validate findings across independent patient cohorts and explore potential underlying immunogenomic mechanisms.

Main Methods:

• Analysis of two independent ICI-treated cohorts (MSKCC, n=1630; Dana-Farber, n=249) to assess overall survival in BRAF-mutant versus BRAF-wildtype patients.
• Multivariate analysis incorporating tumor mutational burden, mismatch repair status, cancer type, age, and sex.
• Immunogenomic feature analysis using The Cancer Genome Atlas (TCGA) dataset.

Main Results:

• BRAF-mutant tumors were associated with significantly better overall survival in both the MSKCC (HR=0.55, P<0.001) and Dana-Farber (HR=0.68, P=0.045) cohorts.
• Multivariate analysis confirmed BRAF mutation as an independent predictor of improved survival (adjusted HR=0.58, P<0.001).
• TCGA dataset analysis suggested diverse immunogenomic mechanisms may underlie immunotherapy response in BRAF-mutant cancers.

Conclusions:

• BRAF mutation status is a significant positive predictive biomarker for overall survival in patients receiving ICI therapy.
• These findings support the clinical utility of BRAF mutation testing to identify patients likely to benefit from immunotherapy.
• The study broadens the understanding of immunotherapy response biomarkers and improves therapeutic prospects for a substantial patient group.