The MESOMARK Assay is a test that is carried out in a lab. It measures the amount of SMRP (serum-measured soluble mesothelin-related peptide) found in a patient’s blood serum. These are the broken-down products from proteins located in the tissue that lines the spaces which surround the lungs, abdomen and heart.

Results which indicate high SMRP levels may be an indicator of the manifestation of mesothelioma, providing detection years before a mesothelioma diagnosis is made.

It is important to note, that some forms of mesothelioma tumors do not release high levels of SMRP (e.g. Sarcomatoid Mesothelioma). The FDA recommends that the MESOMARK Assay should be done in conjunction with other tests to ensure an accurate asbestos related cancer diagnosis.

Unfortunately, as a result, insurance companies may limit the reimbursement for this test.  However, when identified, elevated levels of SMRP have been closely correlated to patients who have been exposed to asbestos and are at a great risk for future development of an asbestos related cancer.

The SMRP assay is a valuable tool in assessing cancer progression and response to treatment.  The elevated SMRP tumor marker aids in mesothelioma diagnosis. Other forms of cancer e.g. ovarian, primary lung or pancreatic cancer may produce a high level of SMRP, as well.

Quick Fact

Results of a study of 1,086 blood samples concluded that 99 percent of health specimens showed SMRP levels at or below the reference value which is used to determine the existence of mesothelioma.

The N-ERC test was created in Japan and has a 95 percent accuracy rate in detecting mesothelioma and has a 76 percent accurate in ruling it out.

This blood test identifies a form of mesothelin known as N-ERC/mesothelin. The test design is comparable to MESOMARK, however, the N-ERC/mesothelin uses an enzyme test which has been specially designed to increase the accuracy of the test.

N-ERC/mesothelin proves to be more accurate than MESOMARK. However, mesothelin is produced by other cancers besides mesothelioma. Therefore, it may not be the sole means of mesothelioma diagnosis.

N-ERC/mesothelin is most accurate in identifying epithelial mesothelioma compared to sarcomatoid mesothelioma. Epithelial cell types produce more mesothelin than the cell types of sarcomatoid.

Additional biomarker blood tests screen for osteopontin and MPF (megakaryocyte potentiation factor). The biomarkers are measured using a method known as ELISA (enzyme-linked immunosorbent assay). These biomarkers are found to have significantly greater levels in the blood of patients with mesothelioma compared to healthy patients or patients with other forms of cancer.

Both MPF and Osteopontin lack specificity as diagnostic markers and, therefore, the dependency necessary to make a formal diagnosis. In other words, there is not a high enough likelihood that a positive test result is enough to diagnose a patient with mesothelioma. However, the blood tests that depend on these biomarkers are able to play a substantial role in monitoring the disease.

Blood test analysis can also find the presence of MPF (megakaryocyte potentiation factor). This is a soluble protein which is made by another mesothelin precursor protein. The biological function of MPF is still not fully understood. However, doctors have discovered that extremely high quantities of MPF are released into the blood stream by mesothelioma patients.

Laboratory technicians, in a small study, did not find MPF in the blood of healthy donors. MPF, however, was identified in the blood serum of 91 percent of late-stage patients. Similarly, Pancreatic and ovarian cancer can produce elevated levels of MPF as well.

Researchers also measured the MPF levels of four patients before and after debulking surgery. Researchers found that MPF levels decreased immediately following the surgery of two of the patients. Surgery was only able to remove 10 percent of the tumor in another patient. As a result, the post-surgical MPF levels did not change significantly. This research suggests that MPF blood testing may aid in monitoring a patient’s response to debulking surgery.

Mesothelioma blood tests show enormous potential as a means for identifying the disease and predicting its outcomes. Researchers continue to work with hope that with continued research mesothelioma blood tests may one day be sensitive enough to reliably provide doctors with a low cost minimally invasive means of diagnosing mesothelioma.