Pleural mesothelioma is an asbestos-related malignant cancer that causes tumors to develop in the mesothelial layer which surrounds the lungs. It the most common form of mesothelioma, responsible for 75% of the 3,000 cases that are diagnosed each year.
Pleural mesothelioma, like other forms of the aggressive disease, may take 20 to 50 years to develop. This “latency period” is the time between asbestos exposure and the development of pleural mesothelioma. Because the cancer is so rare and highly aggressive, it is important that victims seek assistance from a mesothelioma specialist who has expertise and experience in treating pleural mesothelioma.
About Pleural Mesothelioma
The pleura is a soft tissue surrounding the lungs which contains a layer of cells, known as the mesothelium, which may develop into mesothelioma. Pleural mesothelioma is caused by inhalation of asbestos, a naturally-occurring, thin, fiber-like substance that can lodge in the tissues of the lungs. After a period of time, these fibers may cause inflammation, cell mutations and the growth of plaques, which then go on to form malignant tumors.
Nearly all cases of pleural mesothelioma are related to asbestos exposure which was widely used as a high-heat insulator until the 1970s. After 1973, the U.S. government began to limit the types of asbestos applications that may be used and though it is no longer in widespread use, some products do still contain asbestos.
Most cases of asbestos exposure occurred in those working in certain industries such as steel work, auto manufacturing, pipe fitting, ship builders, demolition and certain types of construction. In some cases however, family members of those industrial workers may have been exposed to asbestos when dust was transported into the home on contaminated clothing or by those whose homes or buildings were under construction or remodeled with asbestos-containing products. Any of these types of exposure to asbestos may have resulted in the development of pleural mesothelioma.
Mesothelioma tumors may also develop in different locations of the body including:
- Abdomen – Peritoneal Mesothelioma
- Heart – Pericardial Mesothelioma
- Scrotum – Testicular Mesothelioma
Pleural Mesothelioma Symptoms
Symptoms of pleural mesothelioma are caused by tumor growth and inflammation which may result in fluid collecting in the thoracic or chest cavity. Symptoms of pleural mesothelioma often include:
- Dry cough – caused by inflammation of the outer lung layers
- Persistent cough – may become worse as the disease progresses
- Shortness of breath – caused by lung hardening due to tumor growth, tissue swelling and fluid collection
- Chest pain – due to tumor growth and fluid collection in the chest cavity
- Difficulty swallowing – due to constriction of the esophagus in the chest cavity
- Fatigue – a general symptom of cancer and difficulty breathing
- Weight loss – due to swallowing difficulty and also a general symptom of cancer
Symptoms of pleural mesothelioma may develop slowly over time and become worse as the cancer progresses.
Diagnosing Pleural Mesothelioma
The latency time of pleural mesothelioma development after asbestos exposure is 20 to 50 years and because the cancer so rare, symptoms may often mimic other health disorders, making diagnosis difficult and delayed.
When symptoms are persistent and do not resolve over time, imaging studies will likely be performed. These tests may include:
- CT Scan
- PET Scan
Once imaging studies have shown suspected cancer, blood tests may be used to identify certain proteins released by pleural mesothelioma cancer cells. Results of blood testing and imaging studies will likely be confirmed by a biopsy of the tumor location with microscopic examination to identify cancer cells.
Staging of Pleural Mesothelioma
After diagnosis is confirmed, pleural mesothelioma will be classified into one of four “stages” with Stage 1 being the least developed and Stage 4, the most advanced. The stage of cancer will help identify appropriate treatment options and determine the patient’s prognosis or how likely treatment may be successful.
There are several different systems for staging of pleural mesothelioma but the most common is the IMIG system, which is similar to the TNM system but more specific for pleural cancers. The system classifies the cancer into stages based on tumor size (T), lymph node involvement (N), and migration or metastasis of the cancer (M).
Stage 1 – Tumor is localized in the pleural space and there are no cancer cells in close-by lymph nodes. Pleural mesothelioma is rarely identified at Stage 1 due to disease latency and symptoms that mimic other disorders.
Stage 2 –Tumor(s) are larger but have not spread far beyond pleural area and some local lymph nodes contain cancer cells.
Stage 3 – Tumor(s) are significantly larger have penetrated into surrounding tissue. There are also greater numbers of cancer cells in more lymph nodes that may be further away from the lungs.
Stage 4 – Mesothelioma cancer has traveled to distant parts of the body and tumors of pleural mesothelioma tissue may have developed on other organs including the kidneys, liver, brain and others.
Treatment of Pleural Mesothelioma
Treatment options for pleural mesothelioma are determined by the stage of the cancer and the specific type of cells identified in biopsy. The patient’s severity of symptoms, general medical state and other conditions may also affect treatment choice.
In earlier stages, pleural mesothelioma may have more treatment options with a greater rate of success. In the latest stages, treatment options are limited.
- Surgery – surgical removal of the tumor(s) and a margin of healthy tissue will be required in 20% or more pleural mesothelioma cases. In earlier stages, a pleurectomy will be used to remove only the tumor but in later stages, an extrapleural pneumonectomy or removal of the entire lung may be required. Pneumonectomy is much more invasive but is also more effective, particularly when performed early.
- Traditional chemotherapy – medications are often given to kill pleural mesothelioma cancer cells through IV infusion or oral routes. Chemotherapy may be used in addition to other treatments to make sure that all cancer cells are killed. It may also be used to shrink tumor size to make surgery more successful or as a tumor-shrinking treatment to relieve patient symptoms and increase quality of life, even when prognosis is poor.
- Radiation – focused and concentrated energy beams are used to kill tumor cells. Older forms of radiotherapy are not as useful in pleural mesothelioma due to the location of the tumors and risk of further lung damage but newer treatments are more focused with computer imagery guidance. Radiation may be used before surgery to or as a palliative measure when tumor is large and producing significant patient discomfort.
- New therapies – investigational or clinical trials are ongoing throughout the U.S. Newer medications and procedures, while not yet approved, may be promising in the treatment of pleural mesothelioma.
Pleural Mesothelioma Treatment Cost
The cost of pleural mesothelioma is high. Because a clear link to mesothelioma and asbestos exposure has been shown, some victims have filed lawsuits against industry participants and received monetary awards in the tens and hundreds of $millions. A relief fund was also established, which contains an estimated $30 billion was established to aid victims with disease-associated costs. These costs may include medical treatment, loss of wages and loss of life.
For victims or family members of those diagnosed with pleural mesothelioma, compensation may be available but each case is unique. Those affected by this aggressive cancer should seek advice from a legal expert who specializes in mesothelioma.