Biomarker Testing in Rare Cancers

Because biomarker testing can be performed on tumor tissue or blood, anyone with cancer can receive it.

Yes. Biomarker testing is a critical tool for identifying targeted treatments or immunotherapies that might be effective for a particular patient. It can also be helpful in providing more precise diagnoses in people who have developed rare cancers. Biomarker testing should be a part of every rare cancer patient’s care.

Don’t be afraid to advocate for biomarker testing with your doctor. You have a right to know more about your tumor sample and to see your full biomarker test report. If your doctor doesn’t want to test for relevant biomarkers, you have the right to seek a second opinion, or pursue a test from an company who specializes in biomarker testing.

Once biomarker testing results are returned, the next step is to determine if any of the mutations are actionable – if any of the cell changes that are driving tumor growth can be targeted with an available drug. Targeted therapies work differently in different people, and even if your results indicate a biomarker that matches an available treatment, the therapy may not work for you. However, research has shown that treatment led by biomarker testing extends patients’ lives. Talk to your doctor about the results of your biomarker test and ask how they impact your treatment options.

The cost of biomarker testing varies widely in the United States depending on the type of test you get, the type of cancer you have, and your insurance plan. For some people with advanced cancer, biomarker tests may be covered by Medicare and Medicaid. Additionally, private insurance providers often cover the cost of biomarker testing if there is proof that the test is necessary to guide treatment decisions. Tests without enough documented proof to support their value may be considered experimental and are unlikely to be covered by insurance. However, most biomarker testing companies offer extensive financial support programs.

For tumor biomarker testing, a sample of your cancer cells will be taken during either surgery or a biopsy. For blood biomarker testing, also known as a liquid biopsy, you will have a blood draw. Your samples will then be sent to a special laboratory where they can be tested for certain cancer biomarkers that may be responsible for driving your cancer’s growth. If biomarkers are found in your cancer, it will help your care team identify treatments that can target these drivers. The lab will create a report of their findings for you and your healthcare team to discuss.

For some types of rare cancers, and at some institutions, biomarker testing is part of the standard of care and your doctor may test for biomarkers without you having to ask. In other cases, biomarker testing is done upon request. Regardless, you should ask your care team whether biomarker testing is being carried out. For others, biomarker testing is done at university hospitals and major cancer centers when requested.

There are also private, independent companies that conduct biomarker testing, such as Foundation Medicine, Tempus, Caris, and many more.