Malignant mesothelioma is a rare form of cancer linked to asbestos exposure. The disease attacks the mesothelium; a thin double-layer membrane lining that surrounds the body’s internal organs such as the lungs, heart, chest and the abdomen. Mesothelioma is categorized based on the area where it originates. Mesothelioma that affects the chest and lungs is called pleural mesothelioma, while mesothelioma that affects the abdomen and the heart are called peritoneal mesothelioma and pericardial mesothelioma, respectively. Additionally, in rare cases, mesothelioma may also originate in the tunica vaginalis, also known as testicular mesothelioma.
Pleural mesothelioma is the most common form of mesothelioma, making up of about 75% of mesothelioma cases, followed by 10 to 20% of cases of mesothelioma affecting the abdomen.
Malignant mesothelioma is almost exclusively caused by exposure to asbestos. When asbestos particles are swallowed or inhaled into the respiratory system of the patient, it can potentially cause aggravation and growth of cancerous cells on the membrane surface.
Close to 3,000 people are diagnosed with mesothelioma annually. These individuals may have been exposed to asbestos in their occupation as it was used extensively as an insulator and fire retardant. Those who are at a greater risk of asbestos exposure are:
Additionally, asbestos fibers can lodge in worker's clothing and hair making it possible for their family to be exposed to the dangerous toxins. This type of exposure is called secondary exposure.
Residential houses and schools have also fallen victim to the widespread use of asbestos. Many ceiling tiles, piping and other parts of the foundation were covered with asbestos. Once these fibers break free and become airborne they can become extremely toxic to those in the vicinity.
Symptoms and signs associated with mesothelioma include coughing, fatigue, pain in the chest wall, side, back or abdomen, weight loss, accumulation of fluid in the abdomen, shortness of breath and coughing up blood.
Since these symptoms are similar to other diseases, they are often ignored initially until the condition becomes more serious. Unfortunately, it normally takes between two to three months after symptoms are experienced before malignant mesothelioma is diagnosed.
When looking to confirm a suspicion of mesothelioma, physicians will often using imaging scans such as MRIs, PET scans, chest X-rays, or CT scans. Also, a biopsy may be employed in order to identify the location, size and type of tumor. Other methods often used to help diagnose the cancer include blood tests, tissue tests and fluid tests. A diagnosis will also determine whether the tumor is benign (not cancerous) or malignant (cancerous).
Even though benign tumors are completely resectable, if not surgically removed they have a tendency to become cancerous. Moreover, even once they are removed, a precautionary ten-year monitoring period is often recommended.
There are three main histological types of malignant tumors – Epithelial, which makes up 50 to 60% of malignant mesothelioma cases; Sarcomatoid, which comprises 10 to 20% of malignant mesothelioma cases; and Mixed/Biphasic, which makes up 30 to 40% of malignant mesothelioma cases.
After a diagnosis is made and the tumor location and type is identified, the next step is to determine how far along the cancer is. Staging is used to determine whether the cancer has spread, the extent of the spread and whether they can be removed with surgery. Generally, there are four stages of mesothelioma. It is best to catch the cancer in its early stages for a more favorable prognosis.
Once physicians are aware of the stage of mesothelioma that they are dealing with, they can then move forward and discuss treatment options. Options for treatment are based on the tumor location and type, stage of cancer as well as the patient’s age, weight and general health condition. Conventional treatments for malignant mesothelioma include chemotherapy, radiation and surgery, or a combination of the three. Chemotherapy involves the use of drugs to destroy cancer cells; it can also be used to enhance the result of radiation treatment or destroy returning cancer cells. Radiation on the other hand is used to curb cancer cells from growing and spreading.
Some malignant mesothelioma can be treated with surgery, usually if it is caught in an early stage. Palliative surgery is an option to reduce pain or eliminate fluid buildup but it is only used for symptomatic relief and will not cure anyone of the cancer. Another option is the more complex curative surgery known as extrapleural pneumonectomy, which involves the intricate reconstruction of the affected mesothelium cells with prosthetics.
Malignant mesothelioma can be treated; these treatments can reduce pain, curtail cancer growth and significantly improve the quality of patient’s lives while prolonging lifespan. However, malignant mesothelioma cannot be cured entirely and can potentially relapse.