The MESOMARK assay is a manual enzyme-linked immunosorbent assay for the quantitative measurement of Soluble Mesothelin-Related Peptides (SMRP). SMRP is a biomarker that is released into the bloodstream by mesothelioma cells. SMRP can be elevated years before an actual diagnosis of mesothelioma is made. By measuring the amount of SMRP present in the bloodstream, the MESOMARK assay will help physicians routinely monitor individuals with the greatest risk of developing mesothelioma due to asbestos exposure.