Mesothelioma can be very difficult to diagnose. This is because there are many different types of cells that can make up a mesothelioma tumour. Mesothelioma tumour cells are very similar to some types of lung cancer cells. Sometimes it can be very difficult for a pathologist to decide whether or not the cancerous cells are mesothelioma cells, lung cancer cells or even, sarcoma cells.


To help with diagnosis, scientists are trying to find a tumour marker for mesothelioma. A tumour marker is a chemical given off by cancer cells that can be found in the blood and picked up in a blood test. If a definite tumour marker could be discovered for mesothelioma this would be of great benefit for doctors in making more accurate diagnosis of this disease and may also be helpful to monitor the success of treatment.


An Australian paper, published in The Lancet in November 2003, is about this search. The researchers were looking into tests for proteins related to mesothelioma. This is early research, but they have had promising results. In their study, 84% of people with mesothelioma tested positive, compared to 2% with other cancers or other lung disease. In a group of people who had been exposed to asbestos but did not have mesothelioma, 7 out of 40 tested positive. 3 of these 7 developed mesothelioma and another got lung cancer within 5 years of the positive test. None of the 33 people who tested negative got mesothelioma within the 8 years following the study. It may be that researchers can build on this work to develop a test for screening for mesothelioma and tests for monitoring the disease in people who already have it.


Source: Cancer Research UK