Asbestos is the name for a group of naturally occurring silicate minerals that can be separated into fibers. The fibers are strong, durable, and resistant to heat and fire. They are also long, thin and flexible, and can be woven into cloth.
During the Industrial Revolution of the late 19th and early 20th centuries, companies began manufacturing products that capitalized on these qualities. Over the years, asbestos has been used in thousands of consumer, industrial, maritime, automotive, scientific and building products. Products include building insulation, pipe covering, roofing materials, insulated electrical wires, auto parts and vinyl floor tile. In the U.S. alone, some 30 million tons of asbestos have been used in industrial sites, homes, schools, shipyards and commercial buildings.
Asbestos and Mesothelioma
By the 1930s, it was known that exposure to asbestos can cause life-threatening illnesses, including asbestosis, and lung cancer.
Mesothelioma, which is the most serious asbestos cancer, because it is almost never curable, is a rare form of cancer that forms in the thin tissues (mesothelium) that surround and protect our internal organs and helps the lungs contract during breathing. Mesothelioma develops from inhaling asbestos fibers. The fibers are microscopic and sharp, like splinters, and they irritate and scar lungs and other organs. The body’s defense mechanisms try to remove or capture the fibers, but many fibers still remain in the body and are potential disease-causing agents
Who Can Develop Mesothelioma?
A history of asbestos exposure in the workplace is reported in the majority of mesothelioma cases. People who work in industrial sites such as factories, construction, shipyards, power plants and refineries are at risk for developing mesothelioma if their workplaces contained asbestos. Mesothelioma occurs more often in men than in women.
Family members of those employed at workplaces with asbestos are also at risk. Workers may come home with asbestos fibers on their clothes, the fibers circulate in the air, and family members breathe in the fibers. This is called paraoccupational exposure. Approximately 70 to 80 percent of mesothelioma cases result from occupational and paraoccupational exposure to asbestos fibers.
People who live near readily documented sites that have asbestos are also at risk. Asbestos fibers from those sites can drift into and contaminate residential neighborhoods.
Also, both cosmetic and industrial talc often contain significant amounts of asbestos, and also cause mesothelioma.
While mesothelioma is relatively rare, approximately 3,000 new cases are diagnosed in the U.S. each year. Unfortunately, the average survival time for mesothelioma victims is 10 to 14 months.
It usually takes a long time before mesothelioma symptoms appear (on average 20 to 50 years) after first exposure, and it is often challenging to diagnose mesothelioma because its symptoms are common to many types of infections and cancers.
Types of Mesothelioma
Malignant mesothelioma is diagnosed in one of four forms: pleural, peritoneal, pericardial, and testicular
Pleural mesothelioma is the most common type of mesothelioma, making up approximately three quarters of the mesothelioma cases diagnosed each year. Pleural mesothelioma is a cancer of the pleura. The pleura is the lining around the lungs and it has different parts or layers. The space between the layers of pleura is called the pleural cavity and it contains fluids. If you have pleural mesothelioma, you may develop excess fluid in your pleural cavity or lungs.
Symptoms include:
- Shortness of breath
- Coughing, wheezing or hoarseness
- Blood in coughed up fluid
- Fatigue or anemia
- Chest pain due to accumulation of fluid around the lungs, in the pleural space
Peritoneal mesothelioma is the second most common of the mesothelioma types. It affects about 20 percent of the people who are diagnosed with mesothelioma. The peritoneum is the mesothelium or membrane that lines your abdominal cavity and all the organs inside it.
Symptoms include:
- Unusual loss of weight
- Pain in the abdominal area
- Bloating or swelling (caused by excess fluid in the peritoneal cavity)
- Blockage of the bowels
- Anemia
Pericardial mesothelioma makes up a few percent of all recorded mesothelioma cases. Like pleural and peritoneal mesothelioma, the symptoms of pericardial mesothelioma closely resemble the symptoms of other heart conditions, usually delaying diagnosis.
Symptoms include:
- Heart palpitations or irregular heartbeat
- Chest pain
- Heart murmur
- Difficulty breathing, even at rest or lying down
- Fever or night sweats
- Cough
- Fatigue
Testicular mesothelioma is rare (less than 1% of mesothelioma cases).
Symptoms include:
- Fluid buildup in the testicles
- Swelling of the scrotum
- Pain or a lump in the testes
Mesothelioma Screening Methods and Treatment
After a preliminary physical examination, your doctor may order the following procedures to find out more about your condition:
- X-rays use a type of radiation to create images of the inside of your body.
- CT Scans use a spiral CT scan to produce a clear cross-sectional image allowing a radiologist to see distinct aspects of the lung or pleura not readily apparent from a standard X-ray image.
- Thoracoscopy uses a scope to look inside your chest cavity. A small cut will be made in your chest and a small piece of tissue may be removed for examination (biopsy) during the procedure. While you may feel some pressure, there is usually no pain.
- Peritoneoscopy uses another specialized instrument that allows for examination inside your abdomen and a biopsy specimen may be taken.
Standard treatment options include radiation therapy, surgery and chemotherapy. In some instances, these are combined. While treatments are available for some people with mesothelioma, they are mostly used to improve the quality of life of people whose survival prospects are typically measured in months and not years.