Malignant Mesothelioma
The cancerous form of a tumor that forms in the mesothelium, or lining of the body's organs, is referred to as malignant mesothelioma.
Malignant mesothelioma has only one known cause - exposure to asbestos. It develops when tiny asbestos fibers are inhaled and lodge in the lining of the lungs (and in some cases the lining of the heart or abdominal cavity). Because asbestos is such a durable material, once the fibers are inhaled and embed themselves in the mesothelium, they cannot be expelled.
Eventually, the fibers cause chronic inflammation followed by scarring of the lungs, which can lead to diseases such as pleural plaques and asbestosis. However, in some cases, the asbestos fibers do additional damage and tumors can develop. While the tumors can sometimes be benign, in most cases, they are malignant.
Types of Malignant Mesothelioma
There are three types of malignant mesothelioma:
Pleural - This is the most common form of the disease, affecting the lining of the lungs, known as the pleura. This variation of the disease accounts for approximately 75 percent of all diagnosed cases.
Peritoneal - In some cases, asbestos fibers are inhaled and transported through the lymph node system to the peritoneal cavity or are ingested and make their way to the intestinal tract and become lodged in the peritoneum, the lining of the abdominal cavity. Peritoneal malignant mesothelioma is the result. This form of the disease accounts for about 15 percent of all mesothelioma cases diagnosed annually.
Pericardial - The rarest form of all malignant mesotheliomas, this cancer results when asbestos fibers become lodged in the lining that protects the heart, known as the pericardium. Less than 10 percent of all mesothelioma cases are pericardial in nature.
Diagnosis of Malignant Mesothelioma
Symptoms for all three forms of malignant mesothelioma are similar and often take 20-50 years to develop. They include shortness of breath, chest or abdominal pain, chronic coughing, fatigue, loss of appetite, and weight loss. These symptoms, unfortunately, sometimes mask themselves as other, less-serious diseases. That's why it is important that your doctor know that you've been exposed to asbestos so that he may consider a diagnosis of an asbestos-related disease, even if the exposure occurred decades ago.
Diagnosis will probably include the use of some sort of sophisticated imaging procedure, such as a CT scan or MRI. Those tests are usually followed by a biopsy in order to confirm the presence of cancer cells.
Treatment of Malignant Mesothelioma
Unfortunately, at this time, doctors cannot offer any treatments that will cure mesothelioma, since it is often not diagnosed until it reaches Stage III or IV. However, most oncologists will recommend the use of chemotherapy or radiation, or a combination of both, known as multi-modal therapy. Surgery is indicated in some rare instances. Other procedures, such as thoracentesis (the draining of fluid around the lung), can also be used to keep the malignant mesothelioma patient more comfortable.