A multi-institutional team of researchers have demonstrated that tumor mutation burden may be a useful way to predict a response to checkpoint-inhibitor immunotherapy across different types of cancer. The findings recently published in Nature Genetics.
Patient outcomes to immune-checkpoint immunotherapy vary, understanding exactly how and why some patients do not respond to immunotherapy would save precious time for those patients who will not benefit from it, allowing doctors to prescribe a more effective treatment.
In this study, the team of researchers assessed clinical and genomic data from 1662 patients with advanced cancer who had been treated with immune-checkpoint inhibitors as well as 5371 patients who had not.
The authors sequenced a panel of cancer-related genes in tumors from patients with metastatic disease and quantified the extent to which each patient’s tumours had mutated (also known as ‘tumour mutation burden’).
They demonstrated that patients with tumors that had mutated more extensively had better overall survival rates after checkpoint-inhibitor immunotherapy. However, different cancer types appeared to have different levels of mutation thresholds associated with an improved likelihood of survival.
Overall, these findings suggest that tumour mutation burden may prove to be a useful metric to predict a patient’s response to checkpoint-inhibitor immunotherapy across different cancer types.
Sources: Samstein RM, Lee C, Shoushtari AN et al. Tumor mutational load predicts survival after immunotherapy across multiple cancer types Nat. Genet. doi:10.1038/s41588-018-0312-8 (2019)(Epub ahead of print); www.natureasia.com/en/research/highlight/12827