Mesothelioma is a cancer which is caused by asbestos exposure, and which almost always has a very poor prognosis. A recently published study, however, is investigating biological prognostic factors in order to better determine the proper treatment for mesothelioma patients.
The Annals of Thoracic Surgery has recently reported on the study, which focused on 27 patients with malignant pleural mesothelioma, 14 patients with reactive mesothelium and 10 patients with normal mesothelium. The researchers noted that a specific growth factor, placenta growth factor (PIGF), is more overexpressed in mesothelioma than in reactive mesothelium. Additionally, they found that there was an inverse relationship between survival time and the degree of PIGF expression and higher levels of PIGF expression indicated shorter survival time. There was, however, no correlation between tumor stage and either survival time or PIGF expression.
The patients with malignant pleural mesothelioma who were studied were also all undergoing extrapleural pneumonectomy, a form of surgery which removes not only the lung but also pleural tissue closest to the malignancy.
Mesothelioma is newly diagnosed in around 3,000 Americans each year. Most of those will die from the disease within two years, and many have a much shorter prognosis. Research is ongoing into treatment, but currently there is no cure for this rare form of cancer. Traditional therapies meant to slow or stop the progression of the disease, such as surgery, chemotherapy and radiation, are either not feasible or inadequately effective. Mesothelioma is usually not diagnosed until it has reached a later stage, which means that the patient is already too weak to be a good candidate for these treatments.
The research reported in the new study can help determine a treatment plan for patients, and eventually may be able to prolong their life expectancy.
The authors of the study said, ”We have shown that PIGF can be overexpressed in malignant pleural mesothelioma. In addition, the finding of an inverse relationship between PIGF expression levels and survival suggests a pivotal role of this factor in the recurrence and progression of mesothelioma after extrapleural pneumonectomy.”