Tumor Mutational Burden (TMB), defined as the number of mutations within the coding region of tumor genome, is a new clinical marker which predicts the I-O therapy’s responses in a wide range of advanced tumors. It is believed that tumors with higher levels of TMB express more neoantigens which can be recognized by the immune system as non-self and therefore provides a more robust and durable response to I-O therapy.
TMB can be analyzed by the most recent sequencing technology (NGS) which is designed to cover 170 genes which are associated with the most common solid tumors. This enrichment-based targeting panel simultaneously analyses DNA and RNA and covers a wide range of genes and variants of the most well-known oncological pathways, thus obtaining a complete and profound vision of cancer genetics.
It has been shown that multigene panels such as the 170 genes, can measure precisely the TMB without complete exome sequencing. There is an increasing number of clinical trials demonstrating the potential benefits of TMB as a diagnostic marker regarding precision, sensitivity, and reproducibility. So at the moment, TMB can be considered as the best quantitative parameter that can be used for treatment decision-making.
The panel can evaluate fusions, splicing variants, insertions/deletions, single-nucleotide variants (SNVs) and amplification in a single analysis from DNA and RNA tumors, thereby optimising the use of the sample and the speed of turnaround time.
The report will contain the mutations found in a tumor with the relevant treatment indications and the presence of any ongoing clinical trials.