Mesothelioma is a rare form of cancer that develops in the Mesothelial cells, and is the most serious of all asbestos-related diseases. These cells exist within the mesothelium, which is the sac that lines and protects vital organs such as the heart, the lungs, and the abdominal cavity (stomach). This disease causes the cells of the lining to become abnormal and malignant. About two thirds of all mesothelioma cases develop in the pleural mesothelium or lung lining. About one third, develop in the abdomen. Occassionally, mesothelioma can occur in other mesothelial tissue, such as around the heart or in the reproductive organs.
Three subtypes of mesothelioma have been identified according to microscopic appearance; these are epithelial, sarcomatoid, and mixed types.
Mesothelioma causes the cells of the Mesothelium to become abnormal and infinitely reproduce. A normal Mesothelium cell (or any cell for that matter) can only reproduce a certain amount of times. This keeps certain cells from invading other cells. Cancer occurs when those cells become mutated and their limits are removed, allowing them to reproduce uncontrollably. These abnormal cells then form a lump that is known as a tumor. In a benign tumor, the abnormal cells do not spread into surrounding areas, but malignant tumors do have the ability to spread. When the cancer cells reach a new site, they may continue to divide and form a new tumor, which is referred to as a Secondary Tumor or a Metastasis.
When cancer spreads from one part of the body to the lung, it does so through tissue. The cancer invades the surrounding normal tissue, through the lymph system, and invades the lymph system, traveling through the lymph vessels to other places in the body, and/or through the blood. Once the cancer invades the veins and capillaries, it may then travel through the blood to other places in the body. Once cancer cells break away from the primary tumor and travel throughout the body, there is the potential for a secondary tumor to occur. This entire process is called metastasis
In these cases of metastases to the lung and pleura, breathing difficulties almost always result.
Detecting mesothelioma will often require an additional Positron Emission Tomography (PET) scan to rule out extra-thoracic metastasis and Computerized Tomography (CT) scan imaging.
In cases in which mesothelioma is diagnosed early an oncologist may opt to perform a surgical procedure. Oncologists generally treat inoperable lung cancer patients with the latest chemotherapy or radiation treatments; all of which are under review by the medical community at large to determine their effectiveness, mainly through experimental clinical trials. These clinical trials offered to patients nationwide have detected promising results.
Surgical procedures may also be utilized to remove any tissue buildup or blockage caused by a pleural effusion. Surgical procedures are also used to alleviate distressed breathing, or to control the amount of pain experienced by the patient. A parietal pleurectomy or talc pleurodesis, are some of the surgical procedures used to treat mesothelioma.
Pain medication is administered to keep the patient as comfortable as possible, during the term of the disease.

