Malignant pleural mesothelioma is notoriously difficult to treat and doctors often have to try different treatment combinations to produce a response. But how can they know if a particular treatment strategy is working?
A team of researchers in Pisa, Italy suggest that three key biomarkers may be the answer. Soluble mesothelin-related peptides (SMRP), plasma osteopontin (pOPM) and vimentin have all been studied as potential diagnostic tools.
But University of Pisa scientists say these three key markers may also offer an efficient method for clinicians to track how well a mesothelioma tumor is responding to treatment. This could potentially improve mesothelioma outcomes by enabling doctors to change course if they are not seeing the hoped-for results.
Understanding Mesothelioma Biomarkers
Mesothelioma biomarkers are substances found in unusually high quantities in the blood, serum or lung fluid of mesothelioma patients. Because they are either not present in healthy people, or present at much lower levels, they can be valuable for making a mesothelioma diagnosis or for distinguishing pleural mesothelioma from other lung diseases.
The presence of SMRP in the blood indicates damage to mesothelial cells which line the membranes around the lungs. The test for SMRP called Mesomark has become a staple of mesothelioma management in recent years.
Plasma osteopontin is a protein that plays a role in inflammation, including the kind of inflammation caused by exposure to asbestos. Vimentin is another protein. It is expressed in the mesenchymal cells which give rise to all of the body’s connective tissues.
Biomarkers as Mesothelioma Treatment Monitors
To test the value of these three biomarkers as tools for measuring mesothelioma treatmentresponse, the researchers used 219 serum samples from 56 pleural mesothelioma patients.
By calculating the changes in levels of these biomarkers over time and comparing it to each patient’s clinical course, the doctors demonstrated how their levels fluctuated with mesothelioma treatment response.
“SMRP, pOPN, and vimentin showed statistically significant differences between the disease categories stable disease, partial response, and disease progression,” writes mesothelioma researcher Dr. Alessandra Bonotti.
The analysis showed that these three markers were especially helpful in mesothelioma cases where there was either a partial response to treatment or where the tumor had progressed. “Their possible use in stable disease should be better investigated,” concludes Dr. Bonotti.
Bonotti, A, et al, “Serum mesothelin, osteopontin, and vimentin: useful markers for clinical monitoring of malignant pleural mesothelioma”, September 14, 2016, International Journal of Biological Markers, Epub ahead of print