Malignant Pleural Mesothelioma
Pleural mesothelioma is one of the three forms of mesothelioma, the rare form of cancer associated with the inhalation of asbestos fibers. The disease affects the mesothelium, the membrane that serves as a form of lining for most organs. Because asbestos fibers most commonly enter the body when they are inhaled, it is no surprise that pleural mesothelioma, which affects the lungs, is the most commonly diagnosed form of the disease. Pleural mesothelioma accounts for about 75% of the 2,000 to 3,000 cases of mesothelioma diagnosed every year in the United States.
For years, asbestos was used for a wide variety of purposes, and many people have been exposed to the material, dramatically increasing their chances for developing mesothelioma. While the government has cracked down on the use of asbestos, older buildings and equipment may still contain the fiber.
Understanding the Mesothelial Structure
To understand how pleural mesothelioma develops, it is necessary to understand the structure of the mesothelium in the lung. The mesothelium of the lung is actually two layers of membrane; the outer, or parietal, layer serves as a lining for the chest cavity, while the inner, or visceral, layer covers the lungs themselves. Pleural mesothelioma forms when asbestos fibers become caught between these two layers.
While pleural mesothelioma normally develops in either the visceral or parietal layer of the lung’s mesothelium, it can spread to the other layer, and beyond.
Diagnosing Pleural Mesothelioma
Because malignant pleural mesothelioma affects the lungs, most of the noticeable symptoms involve breathing. The most common symptoms of pleural mesothelioma include:
- Chronic dry cough
- Coughing up blood
- Difficulty swallowing
- Difficulty breathing and a shortness of breath, even when not active
- Painful breathing
- Chronic chest pain
- Noticeable lumps developing on the chest
- Inexplicable weight loss
- Chronic fatigue
- Night sweats
Unfortunately, because the symptoms of mesothelioma often take decades to first manifest themselves, it may be difficult to positively identify pleural mesothelioma until the disease has progressed significantly. Additionally, the vagueness of many of the symptoms can lead to a misdiagnosis.
The science behind testing for pleural mesothelioma has advanced by leaps and bounds over the past several decades. X-rays and CT-scans are common, but blood testing is becoming increasingly common. Doctors will also discuss a patient’s personal and family history, and will look for the common symptoms.
Treating Pleural Mesothelioma
Because pleural mesothelioma accounts for three out of every four mesothelioma diagnoses, there has been significant research in the field of treatment. Treatment can include:
- Surgery, in which doctors remove part or all of a lung in order to remove the tumor and prevent the disease from spreading.
- Radiation treatment, in which high doses of radiation are used to kill the cancerous cells. Unfortunately, radiation treatment also kills healthy cells, which can cause side-effects.
- Chemotherapy, in which drugs are used to kill the tumor and prevent the spread of cancer. Like radiation treatment, chemotherapy can result in a number of unpleasant side-effects.
The most modern treatment plans usually involve a combination of all three treatment options, which can dramatically increase a patient’s chances for survival.
Mesothelioma is diagnosed in four different stages, according to how far the disease has progressed. Patients in stages one and two have the most treatment options and have a decidedly higher survival rate. Overall, the three-year survival rate for pleural cancer is approximately 10%, while the five-year survival rate is only 5%. In particularly severe cases, treatment can usually only reduce pain, rather than change the prognosis.
