A relatively rare but deadly cancer, mesothelioma kills between 15,000 to 20,000 people around the world every year. This aggressive form of cancer is strongly linked to exposure to asbestos, a thread-like mineral once popular in building materials and insulation for the strength, durability, and fire resistance it provided. Fibers of asbestos can be inhaled and then lodge in the lining of the chest (pleural mesothelium) or abdomen (peritoneal mesothelium), where scarring can eventually lead to the development of cancer.
Early mesothelioma symptoms like shortness of breath, pain in the chest, or fluid build-up around the lungs are easily confused with symptoms of other, less serious lung conditions. Because of this, mesothelioma often goes undiagnosed and hence untreated until the late stages of the disease, when traditional therapies like radiation and chemotherapy are much less effective. As with most cancers, the prognosis for patients with mesothelioma depends largely on how soon it is caught, and new tests are being developed to detect this life-threatening disease before it becomes untreatable.
Last September, researchers from a company called Somalogic Inc announced that they had found measurable changes in the blood of mesothelioma and pancreatic cancer patients. Somalogic’s screening technology measured the presence of aptamers, a type of genetic material that adheres to proteins, in the blood of patients who had been diagnosed but not yet treated for these two types of cancer. Unlike some other tests, these allowed doctors to distinguish between diseases with similar symptoms, such as pancreatic cancer versus pancreatitis and mesothelioma versus lung scarring. The biological markers found in the blood were both specific and accurate. More research is still needed to replicate these results and ensure their reliability, but this type of testing shows definite promise as an early screening method.
Another company, Rosetta Genomics, has been given approval in New York State to perform diagnostic tests of microRNA. These biomarkers regulate protein creation and are highly tissue-specific, allowing doctors to use them to test for the primary tumor site for cancer that has metastasized, or spread throughout the body. A test called “miRview meso” can help diagnose pleural mesothelioma, the most common type of the cancer, where the primary tumor is located in the lining of the chest cavity. In addition to testing, there is some indication that microRNA can be manipulated to help slow the growth of tumors – a very important priority for cancers that develop as fast as mesothelioma does.
Since the cancer spreads so quickly, mesothelioma life expectancy is very low, with the five-year survival rate standing at around 10%. However, new methods of testing for this disease are being developed all the time. Though mesothelioma is nearly always caused by asbestos inhalation, a latency period of 20 to 50 years can elapse before symptoms begin to show. It is therefore imperative that anyone whose job, such as factory work, ship building, or construction, brought them into contact with asbestos consult with a doctor about the possibility of asbestos-related disease. Even if mesothelioma is not yet detectable, evidence of lung scarring can warn of potential future health complications.