Results reported by Australian researchers at the 3rd European Lung Cancer Conference in Geneva, Switzerland show strides being made in the diagnosis and treatment of pleural mesothelioma. Pleural (lung) mesothelioma is the most common form of this deadly disease that kills roughly 3,000 Americans each year.
The researchers have identified that a certain molecule is more plentiful in the blood of mesothelioma patients than in the blood of healthy people. It’s hoped that this discovery will aid in earlier diagnosis of mesothelioma than is currently possible, leading to longer survival rates for mesothelioma patients.
Right now, a lung biopsy with tumor tissue is needed to diagnose pleural mesothelioma. Unfortunately, suitable biopsies are not always available, and this can lead to medical uncertainty and delayed treatment. According to Dr. Michaela Kirschner from the Asbestos Diseases Research (Concord Hospital Campus) in Sydney, “If doctors could use a diagnostic marker based on a simple blood test to help with diagnosis, it could circumvent the problem of availability of tumor tissue and help to accelerate the diagnostic process.”
Though currently a number of proteins have been proposed as markers for mesothelioma, none has yet reached the accuracy needed for routine clinical use.
Dr. Kirschner and her colleagues researched whether molecules known as microRNAs in blood may be diagnostic markers for the disease. In their study, which focused on 5 pleural mesothelioma patients and 3 healthy controls, researchers identified 17 microRNAs. Next, the scientists validated these miRNAs in blood samples from 15 mesothelioma patients and 13 controls. The scientists found that the microRNA known as miR-625-3p was four times higher in the blood of mesothelioma patients than in the control patients.
“Detailed analyses of our two independent sample series have shown that miR-625-3p performs as well as any previously proposed protein marker for detecting mesothelioma,” Dr Kirschner said. “However, like most diagnostic markers, miR-625-3p is not 100% accurate, and therefore there is a chance the assay will produce both false positives as well as false negatives. Further studies on larger sample sizes are needed to see whether the accuracy of miR-625-3p can be confirmed or even turn out to be better than currently observed.”
“Should further studies prove that microRNAs in plasma are accurate enough for the diagnosis of malignant pleural mesothelioma, this will lead to the development of a diagnostic test for routine clinical use,” Dr. Kirschner said. “This test would then represent a relatively simple way to circumvent the problems associated with obtaining a tissue biopsy. For a patient, this would mean that appropriate treatment could be instituted at an earlier stage.”