Serum and pleural fluid biomarkers for mesothelioma

Malignant mesothelioma is an asbestos-induced, aggressive tumour. In centres across the world, research has focused on evaluating biomarkers for malignant mesothelioma screening, diagnosis, prognostication and monitoring. With the incidence of malignant mesothelioma expected to increase, it is timely to review the current status of biomarkers in this field.

The majority of recent studies have evaluated the commercial MESOMARK assay in a diagnostic setting. Studies have clarified that soluble-shed mesothelin as well as mesothelin-related peptide are targets of the assay. The assay sensitivity ranges from 50% at diagnosis to 84% in advanced disease. The assay has a high level of specificity relative to benign lung and pleural conditions and is positive in 10-15% of other malignancies. In a prospective screen of 538 asbestos-exposed workers, 2.8% were positive; one had lung cancer that was subsequently successfully treated. The biomarkers megakaryocyte potentiating factor, osteopontin and CA125, either alone or in combination with soluble mesothelin, have also been assessed.

To date, soluble mesothelin remains the best available biomarker for malignant mesothelioma. However, a lack of sensitivity for early-stage disease and for all malignant mesothelioma histologies provides motivation for the search of novel malignant mesothelioma biomarkers with greater sensitivity, especially for very early disease.