Tumor Mutational Burden (TMB) is an emerging, independent predictive biomarker of immunotherapies in multiple tumor types, including lung cancer.
Refers to the total number of somatic mutations that exist within a tumor’s genome.
A subset of these mutations may result in expressed proteins, termed neo-antigens, that are not recognized by the host’s immune system as self, and therefore have the potential to be immunogenic, leading to an anti-tumor immune-mediated response.
Tumors with a high mutation burden may have a higher rate of neo-antigens which, in principle, would be expected to be more immunogenic than tumors with comparatively low mutation burden.
The test is performed using the Oncomine™ Tumor Mutation Load Assay (409 genes). It is a robust targeted NGS assay, that provides accurate quantitation of somatic mutations to assess tumor mutation burden, in formalin-fixed, paraffin-embedded (FFPE) tissues.