Mesothelioma Blood Tests and Biomarkers

To ensure an accurate diagnosis, your medical professionals may combine several tests, scans, and imaging to be as precise as possible.

Often, the final confirmation and diagnosis will come from a combination of x-rays, CT scans, and MRIs, as well as blood tests and biopsy results. The tests are looking for specific proteins that are unique to mesothelioma, called biomarkers. Some of the most common blood tests include the N-ERC/Mesothelin test, the Mesomark assay, and the Fibulin-3 test.

What are Mesothelioma Blood Tests and How Do They Work?

Mesothelioma blood tests look for biomarkers in the blood that are only produced by the cancer cells of mesothelioma.

Usually, one or more blood tests are used in conjunction with imaging scans in order to boost the speed and accuracy of a mesothelioma diagnosis. 

The primary biomarker tests are:

• The Mesomark Assay – The Mesomark assay measures the quantity of a protein called SMRP, or serum-measured soluble mesothelin-related peptide, in a given blood sample. This is useful in diagnosing only a portion of cases since some cases like sarcomatoid tumors do not produce high enough levels of SMRP.
• N-ERC/Mesothelin test – The N-ERC/Mesothelin test looks for a particular form of mesothelin known as N-ERC/Mesothelin. This makes it more accurate at detecting, but less accurate at ruling out mesothelioma. Just like the Mesomark, the N-ERC/Mesothelin test must be combined with other tests to ensure accuracy and pathology.
• The Fibulin-3 Test – This test is designed to indicate the presence of Fibulin-3 protein. Fibulin-3 is produced by mesothelioma and can be detected in both blood and pleural fluid. It is known for being highly accurate with both detecting mesothelioma and ruling it out in those without the disease as well.

The tests work by identifying specific biomarkers that are not created by healthy cells but are created in measurable amounts by mesothelioma tumors. Not only do the markers indicate the presence of mesothelioma, but in some cases, they can also be targeted directly in order to treat mesothelioma more effectively.

Other Biomarker Tests

There are other tests that can be done to search for other markers that could lead to increased accuracy or confidence in the diagnosis.

Tests exist for both the levels of osteopontin and MPF or megakaryocyte potentiating factor, which have both been shown to be present in higher quantities in patients with mesothelioma than in healthy patients.

Neither the osteopontin nor megakaryocyte potentiating factor tests are accurate or dependable on their own to make any definitive diagnosis. However, just as with the primary biomarker tests, they can contribute to the overall diagnosis, and can even help monitor the patient’s progress following the diagnosis.

There is an additional biomarker to be found in 8OHdG, which is normally linked to oxidizing cell damage. It has been found in early-stage cancer patient blood samples and higher levels have been found to have a positive correlation with severe asbestosis.