There is a lot going on inside a cancer cell. Oftentimes, cancer forms because of mutations in certain genes and proteins. Tumor mutational burden (TMB) measures the number of mutations in a tumor sample.
TMB is the measure of non-inherited mutations (called somatic mutations). You aren’t born with somatic mutations, they develop over time. The “mutations per megabase” scale (mut/MB) is used to measure TMB. Patients are often classified as “low,” “intermediate,” and “high” TMB.
A high TMB (TMB-H) is usually considered 10 mut/MB or above. Patients with a large amount of mutations may be candidates for immunotherapy.
Immunotherapy uses the body’s immune system to fight off cancerous cells. Because cells with a high TMB carry a large amount of mutations, they are strong targets for the immune cells working to identify and attack abnormal cells.
A TMB measure is most often identified through next generation sequencing (NGS) on tumor tissue.
Each treatment plan depends on your stage, line of treatment, surgical or additional treatment options, and your overall health.
All GI cancers (in advanced, specific situations)
The biomarker status of MSI-H/dMMR may impact eligibility and timing, especially for colorectal cancer patients.
This is also true for the PD-L1 biomarker in gastric and esophageal cancer patients.
Ask your doctor how your biomarker test results are informing your treatment plan and if you qualify for any clinical trials.
