Mesothelioma Researchers Find Biological Marker to Help Diagnose Malignant Mesothelioma

Turkish researchers have recently identified a biological marker known as D2-40 to be helpful in distinguishing malignant mesothelioma from pulmonary adenocarcinomas.

Because pulmonary adenocarcinoma, malignant mesothelioma and benign mesothelioma have great resemblance to one another under a microscope, medical professionals involved in the diagnosis of mesothelioma can experience difficulty in differentiating between the three conditions. This challenge has motivated mesothelioma researchers to search for better diagnostic methods, including discovering biological markers that can easily be tested in a lab setting.

The biological marker D2-40 is an antibody produced by the immune system. It is already in use as a marker for lymphatic endothelium (a type of lymphatic tissue that lines body cavities and certain organs). Researchers have theorized that D2-40 could be particularly beneficial in diagnosing epithelial mesotheliomas from pulmonary adenocarcinomas.

There are three different “histological” types of mesothelioma, including epithelial (the most common type), biphasic and sarcomatoid. Histology is the microscopic study of cell shape, structure and pattern of formation (whether it is round, oblong and so on). A branch of histology, known as immunohistochemistry, uses chemical staining of cell samples under a microscope to identify proteins of the immune system that indicate the presence of disease.

Hence, the fields of histopathology and immunohistochemistry help diagnose malignant mesothelioma and much research is being conducted in these fields to improve diagnosis, treatment and prognosis for mesothelioma patients. In a separate study, another researcher found D2-40 to be present in 86 percent of the epithelial mesotheliomas tested, and additionally in four out of five tested biphasic mesotheliomas (which are a mix of epithelial and sarcomatoid cells). The researcher also found that D2-40 was not present in sarcomatoid mesotheliomas, further supporting the efficacy of D2-40 as a marker for epithelial mesothelioma.

In the Turkish study researchers found D2-40 to be present in 64.3 percent of epithelial mesotheliomas tested. Only one out of the seven biphasic mesotheliomas tested was positive for D2-40. Additionally, the researchers found no statistical difference in malignant mesotheliomas versus benign mesotheliomas, suggesting that D2-40 would not be a good biological marker to differentiate between malignant and benign mesothelioma.

The results were gratifying to researchers, stating, “In conclusion, strong membranous D2-40 positivity is helpful in differentiation of MM [malignant mesothelioma] from pleural involvement of pulmonary adenocarcinoma, so we suggest that it should be included in the IHC [immunohistochemical] panel used for this purpose.”

Additional information about mesothelioma may be found through the Mesothelioma Center.

This entry was posted on Thursday, November 19th, 2009 at 11:51 am and is filed under Mesothelioma, Mesothelioma Research. You can follow any responses to this entry through the RSS feed. Responses are currently closed, but you trackback from your own site.