Pleural mesothelioma is a group of cancers that begins in the lining of the lungs. Caused by asbestos exposure, it is incurable and often difficult to treat.
What Is Pleural Mesothelioma?
Normally, mesothelioma begins with the inhalation of asbestos fibers that become stopped in the lining of the lungs. Once stuck, the carcinogens cannot be removed and will eventually lead to changes in cells’ DNA. The pleura (i.e., the tissue covering the lungs) can develop cancerous tumors from repeated asbestos exposure 10 to 50 years later, known as pleural mesothelioma.
While over 200,000 new cases of lung cancer are diagnosed each year in the U.S., there are less than 3,000 new mesothelioma cases annually. Though mesothelioma is a rare form of cancer, pleural mesothelioma is the most common variant (approximately 3 out every 4 cases are pleural). The average age of patients receiving this type of diagnosis is 72 years old.
Risk Factors and Causes
Most of the people diagnosed with pleural mesothelioma once worked around friable asbestos fibers which they inhaled on the job. Retired individuals whose occupations included industries like construction, asbestos abatement, automobile mechanics, power plants, and the U.S. military. Other causes for pleural mesothelioma include either high levels or repeated exposure to chest radiation and some viruses, though these are substantially rarer.
Additional risk factors that can increase a person’s chances of developing lung disease include old age (because it takes years for tumors to develop), smoking cigarettes, a family history of mesotheliomas, and living with someone who was exposed to asbestos. Generally, family members carry a significant risk of developing mesotheliomas compared to the general population because toxic fibers commonly attach to the skin and clothing of workers. When carried home, the fibers are transferred via skin-to-skin, skin-to-clothing, or airborne contact to other people in the house.
Today, new cases of pleural mesothelioma are due to hazardous exposure to chemicals decades ago. Asbestos, the primary risk factor in developing mesotheliomas in the body, can still be found in many older homes and businesses. Although the manufacture of asbestos has declined, researchers in 2012 believed cases of malignant pleural mesothelioma would climb in the coming decade from inhaling asbestos.
Symptoms and Diagnosis
As there are no short-term effects of asbestos exposure, it can take decades for symptoms of pleural mesothelioma to appear. Moreover, by the time most patients experience any symptoms, the cancer has reached its advanced stages. Because pleural mesotheliomas begin in the lining of the lungs, typical symptoms are linked to the respiratory system and include:
- Chest pain
- Buildup of fluid around the lungs
- Lumps in the abdomen
- Persistent, painful coughs
- Shortness of breath
- Unexplained weight loss
As soon as common signs of pleural mesothelioma appear, it’s important to see a doctor right away. In diagnosing a health problem, doctors often conduct a physical examination, an interview of current symptoms and possible risk factors, as well as tests for lung disease (such as a CT scan, x-ray, blood test, or tissue biopsy).
For most patients, several tests will be administered to diagnose the presence of cancer as well as the type and stage. With this information, doctors can determine the patient’s prognosis (i.e., the most probable progression of the disease). Pleural mesothelioma is the only form of the illness with a formal staging system; the American Joint Committee on Cancer’s TNM (Tumor-Node-Metastasis) system tracks the size of the original tumor, the involvement of lymph nodes, and the metastases to other areas of the body. The more commonly used staging system among patients, however, grades pleural mesothelioma from I (one) to IV (four), where lower numbers indicate a lower amount of cancerous metastasis.
Overall, the prognosis for malignant pleural mesothelioma is poor, and surviving years beyond a diagnosis generally extend from one to a few years. For patients able to withstand “trimodal therapy” (treatment typically including surgical resection, chemo, and radiation), survival beyond two years has been frequently reported.
The five-year survival rate for malignant pleural mesothelioma is an estimate based on past cases of the disease but does not set cancers according to the AJCC TNM stage used by oncologists. Instead, five-year survival rates are based on the localized, regional, and distant spread of tumors.
|Malignant Pleural Mesothelioma 5-Year Survival Rates|
|Localized||Mesothelioma limited to the pleura.||20 percent|
|Regional||Tumors spread to adjacent cells and tissues from the original tumor.||12 percent|
|Distant||Tumors have spread to distant organs and the opposite lung.||8 percent|
|All stages combined||Average of SEER stage rates.||10 percent|
If diagnosed at an advanced stage, most pleural mesotheliomas are incurable and can only be given palliative treatment to extend one’s quality years of life remaining. However, with advancements in diagnosis and treatment research, patients are catching their tumors earlier as well as receiving more effective targeted cancer therapies (such as immunotherapy).
The most common treatments for pleural mesothelioma include surgery, chemotherapy, and radiation. Stages I and II usually receive surgery to remove the primary tumor followed by chemotherapy or radiation to eradicate any remaining tumors, or those too small to remove via surgery. For patients with stage III or IV pleural mesothelioma, chemo and/or radiation may precede treatment to shrink tumors in preparation for surgery.
Being diagnosed with a lung disease caused by corporate negligence can be frustrating and confusing. If you believe your illness is the result of exposure to carcinogens, fill out a free case evaluation form for legal aid and compensation information.