Pleural Mesothelioma

Pleural mesothelioma is a malignant disease that affects the lining of the lungs, or lung pleura. Doctors often times refer to this disease as mesothelioma of the pleura. Mesothelioma should not be mistaken as a primary lung cancer; as it is not. Mesothelioma is a cancer of what is called the serous membranes. These membranes cover a large number of organs in the midsection of the body, including the lungs. Pleural mesothelioma, which is the most common type of mesothelioma affects the serous membranes of the lungs.

This terrible cancer mesothelioma can also affect the serous membranes around the abdomen, and at this point is called peritoneal mesothelioma, and when the membranes surrounding the heart, is affected it is called the pericardial mesothelioma. If the mesothelioma or cancerous cells should spread to the lungs from the serous linings of the lungs, abdomen or heart, it is considered to be a secondary lung cancer. Pleural mesothelioma is oftentimes referred to as an asbestos lung cancer. Technically speaking, any cancer that does not originate in the lungs is not considered to be a lung cancer; this can lead to a misunderstanding about pleural mesothelioma and secondary lung cancer. Asbestosis is defines as a type of asbestos lung disease that originates in the lungs and can oftentimes be confused with mesothelioma.

Pleural Mesothelioma Cancer

Pleural mesothelioma cancer is the diagnosis in about 75 percent of all mesothelioma cases. This disease occurs as a result of an individual coming into contact with and inhaling asbestos fibers, which can settle in the lungs and cause the development of malignant cancerous cells. These asbestos fibers if embedded in the lining of the lung (the pleura) may eventually cause chronic inflammation that eventually leads to the growth of cancerous tumors or,and in some cases, result in asbestosis.

Pleural mesothelioma cancer frequently appears as multiple tumor masses affecting the parietal surface (area further from the lung) and visceral surface (area closer to the lung) of the pleura. In most cases, the parietal surface is more easily affected than the visceral. Studies have shown that their is a slightly higher incidence of mesothelioma in the right lung, apparently this is due to the fact that the right lung is much larger and has a greater amount of pleural surface area. The lower lungs typically shows more tumor masses than the upper lung (right lung). This is believed to be due gravitational forces that influence how the asbestos fibers eventually settles in the lungs after they have been inhaled.

Abnormal growths in the pleura is normally found in patients upon diagnosis. As the diseases spreads, the growth of these cancerous cells results a complete deterioration of the lung cavity. The tumors can oftentimes spread from the lung pleura to other organs in the body,which including the heart and abdomen. Mesothelioma is also known to invade the lymph nodes and circulatory system in some cases.

Tumors that are not related to pleural mesothelioma can also grow in the pleura. These tumors start in other parts of the body and gradually moves to the pleura. The most common form of non-pleural mesothelioma cancer that occurs is lung cancer,whic accounts for about 36 percent of the cancer occurring in the pleura. The next most common forms of cancer are breast cancer which accounts for approximately 25 percent, ovarian cancer 5 percent and gastric cancer 2 percent. Lymphoma also accounts for a very small portion of cancers that metastasize to the pleura.

Pleural Mesothelioma Symptoms

As with many disease pleural mesothelioma comes with many symptoms that may be misleading. The most common symptom associated with pleural mesothelioma patients is a chest pain. However, the pain oftentimes not associated with the lung pleura and often appears in the shoulder or upper abdomen. A shortness of breath, called dyspnea, is also a common symptom associated with this disease. Cough, weight loss and anorexia have been reported in some patients, but are less common symptoms. Finally, the epidemic growth of the pleural mesothelioma tumors enlarges the pleural space causing it to fill with fluid. This buildup of fluid which is known as a pleural effusion causes great discomfort or pain associated with first detection of the disease.

Pleural mesothelioma patients oftentimes have all three types of mesothelioma cancer cells: epithelioid mesothelioma, sarcomatoid mesothelioma and biphasic mesothelioma.

Pleural Mesothelioma Prognosis

Most patients' mesothelioma prognosis is quite bleak. In a study involving 167 patients with proven pleural mesothelioma, the median survival rate of patients following diagnosis was 242 days. The survival rate was also affected by the type of mesothelioma cancer cells; patients with biphasic cell types have the shortest life expectancy.

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