Pleural Mesothelioma
The most commonly diagnosed form of this type of cancer, pleural mesothelioma accounts for about 65 to 75 percent of all cases discovered each year.
What is It?
Pleural mesothelioma is cancer that develops in the pleura, a two-layered membrane that lines the lungs and the area around them. The outer layer, known as the parietal layer, protects the entire chest cavity and the diaphragm while the inner visceral layer protects the lungs. Mesothelioma can develop in either layer though the outer parietal layer is most often affected. In addition, the right lung is more susceptible as well because of its larger size.
Currently, the only proven cause of pleural mesothelioma is exposure to and inhalation of asbestos fibers. A person with this form of cancer probably worked with asbestos on a regular basis and inhaled tiny sharp fibers which become lodged in the pleural area, causing scarring and inflammation (asbestosis) and, in some cases, cancerous tumors.
Pleural mesothelioma, like other forms of the disease, has a long latency period. That means it may take up to 50 years for symptoms of the cancer to develop. Therefore, when it is finally discovered, the mesothelioma has reached its late stages and becomes quite difficult to treat. That is why individuals who are aware of their exposure to asbestos in the past should undergo regularly chest x-rays or lung function tests.
Diagnosis
Diagnosis of pleural mesothelioma can be quite difficult not only because of the long latency period but also because many symptoms of the disease can be mistaken for other ailments, including heart disease or more common illnesses like the flu or pneumonia. Symptoms of pleural mesothelioma usually include:
- Chest pain
- A dry, unproductive cough
- Wheezing
- Hoarseness or a raspy voice
- Difficulty breathing
- Shortness of breath, even at rest
- Pleural effusion (fluid around the lungs)
- Loss of appetite
- Weight loss
The first step to diagnosis usually occurs when the patient visits his/her doctor complaining of these symptoms. At this point, it is essential that the patient share his occupational history with the doctor so that pleural mesothelioma is taken into consideration. Once a thorough exam is done, the doctor will probably suggest a chest x-ray followed by a more accurate diagnostic test like a CT scan or MRI. A biopsy may also be ordered to confirm diagnosis.
Treating Pleural Mesothelioma
Because pleural mesothelioma is the most common mesothelioma type, the most research has been done on treatments for this form of the disease. That said, however, treatments for meso still lag far behind those developed for much more common forms of cancer.
After diagnosis, the patient will be sent to an oncologist and probably a thoracic surgeon who, together, will form a plan for treatment. The most common recommendations are chemotherapy and radiation though surgery is sometimes considered, especially if the patient is younger and in overall good health. Currently, the drug of choice for treating pleural mesothelioma is Alimta©, the only FDA-approved chemo drug designed specifically for the treatment of this disease. Radiation is also used in hopes of shrinking tumors in the affected area.
Patients may also choose to participate in clinical trials or to try alternative or complementary therapies in order to alleviate the symptoms of the disease and/or the side effects of the traditional therapies.
Prognosis
While new treatments for pleural mesothelioma continue to be researched and developed and life expectancies of patients have increased slightly in the last few years, most victims of this disease still die within one or two years of diagnosis and only about 10 percent of patients make it to the 5-year survival landmark.