01. Main Cause of Mesothelioma
What Is the Main Cause of Mesothelioma?
Asbestos is the most common cause of mesothelioma. All types of asbestos are cancerous. Exposure to asbestos accounts for at least 90% of all cases of mesothelioma.
When asbestos fibers are inhaled or ingested, they can become embedded in the lining of the lungs, abdominal cavity or heart. Once embedded, the fibers cause inflammation and scarring that can eventually lead to mesothelioma tumors. Inhaling the fibers can also cause other asbestos-related diseases, such as asbestosis.
In addition to the inflammation and scarring, the asbestos fibers also cause indirect and direct DNA damage.
How Asbestos Damages DNA
- Asbestos interferes with cell division.
- This interference can cause cellular damage.
- As a result of the cellular changes, cancerous mutations may occur.
- Asbestos can cause immune cells to release dangerous gases, which increase inflammation and promotes lung fibrosis.
- Over time, this inflammation can lead to DNA damage and cancer.
The location of the embedded asbestos fibers and damaged DNA determines which form of mesothelioma develops.
- Peritoneal mesothelioma develops in the lining of the abdomen.
- Pleural mesothelioma develops in the lining of the lungs and chest wall.
- Pericardial mesothelioma develops in the lining of the heart.
It often takes 10 – 50 years following asbestos exposure for patients to present mesothelioma symptoms.
How Do You Get Mesothelioma?
Mesothelioma is caused by exposure to asbestos fibers. Asbestos exposure is most common in the workplace. However, exposure may also occur through natural asbestos in the environment or secondary exposure.
Asbestos regulations have increased in recent years, which helps to restrict the use of the carcinogen. However, workplace exposure is still a concern because of the wide past use of asbestos. Among those with the greatest risk of asbestos contact are firefighters and construction workers. These men and women may encounter asbestos when working in older homes and schools.
Asbestos Exposure Outside of the Workplace
Exposure can occur from the natural environment, asbestos products or secondary contact with loved ones.
Secondhand exposure commonly occurs when asbestos fibers are brought home on asbestos workers’ hair, skin and clothing.
Asbestos exposure may also occur among individuals with no connection to asbestos workers. The carcinogen has been found in homes and household items, which may lead to dangerous exposure. Homeowners may experience asbestos exposure when performing do-it-yourself remodeling projects. Homes built prior to 1980 are most likely to have been built with asbestos-containing construction materials.
Household products such as talcum powder, potting soils and paint have also all been found to contain trace amounts of the mineral. Recently, children’s makeup brands have come under fire for selling makeup that contained asbestos-contaminated talcum powder.
Resources for Mesothelioma Patients
02. Mesothelioma Risk Factors
Mesothelioma Risk Factors
Around 90% of all mesothelioma cases are the result of asbestos exposure. However, there are indications other factors may lead to a mesothelioma diagnosis.
Risk Factors for Mesothelioma
- Advanced age
- Presence of BAP1 gene
- Poor overall health
- Simian virus 40
- High aspect ratio nanoparticles
Increased Risk Among the Elderly
One common misconception about mesothelioma is it only develops in the elderly. Although 91% of those diagnosed are 55 years old or older, younger patients have been diagnosed. According to data from the Centers for Disease Control and Prevention (CDC), there were 4,827 mesothelioma diagnoses in patients under 55 years old between 1999 and 2016.
The elevated risk among older individuals is largely due to the long latency period associated with the disease. Studies also continue examining a potential link between young adults’ genetics and their mesothelioma risk. Results from this research could lead to more early diagnoses, changing the age-related statistics of the disease.
Risk in Patients With the BAP1 Gene
The BAP1 gene suppresses tumors. A mutation of the gene increases the likelihood of tumor development. Individuals exposed to asbestos with this genetic mutation may be more susceptible to developing mesothelioma. The presence of this mutated gene is found through histological testing.
According to research from Fox Chase Cancer Center, 60% of mesothelioma patients are identified as having this specific genetic mutation. Researchers also found mesothelioma patients with this genetic mutation tended to be diagnosed at a younger age than those without the mutation. Additionally, patients with this genetic mutation overall had more favorable survival times than patients without the gene. In the patients studied, the mesothelioma cases were largely peritoneal mesothelioma and epithelioid cell type.
Greater Mesothelioma Incidence Among Men
Mesothelioma is not a gender-specific cancer, but does have a higher incidence among men. This correlation may be due to male-dominated asbestos occupations. For example, in the past, more men than women worked in high-risk occupations and areas, such as asbestos mines and shipyards. However, in recent years, women are experiencing higher rates of occupational and secondary asbestos exposure. Research has shown mesothelioma incidence among women is on the rise.
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03. Lifestyle Risk Factors
Lifestyle Risk Factors for Malignant Mesothelioma
Poor Health and Disease
Poor health results in an increased risk of developing diseases, including mesothelioma. Additionally, a weakened immune system hinders the body’s ability to fight the side effects of mesothelioma and the cancer itself.
Can Smoking Cause Mesothelioma?
Research has not definitively proven a link between smoking and mesothelioma. However, the relationship between smoking, lung disease and various forms of cancer is well established. Scientific studies continue to examine the relationship between smoking and mesothelioma.
Currently, there is little evidence smoking alone increases a person’s chance of developing mesothelioma. However, many studies have shown smokers are 50 – 90% more likely to develop asbestos-related lung cancer. Similarly, smokers exposed to asbestos are twice as likely to develop mesothelioma.
According to research, it is possible smoking makes it easier for asbestos to become embedded in the lungs and lead to cancer.
Changes in the Lungs Due to Smoking
When the lung tissue is damaged, asbestos fibers can more easily become lodged in the linings of the lungs.
Smoking can cause many medical problems. Poor overall health can reduce a patient’s mesothelioma treatment options and life expectancy.
Irritation of the air passages causes them to produce more mucus. This blocks the passage of air and affects the lungs’ ability to cleanse themselves.
Cigarette Filters and Asbestos
Cigarettes contain thousands of chemicals. According to the International Agency for Research of Cancer (IARC), at least several dozen of these chemicals are carcinogens. To make cigarettes “healthier,” some brands add filters intended to remove a portion of these substances. However, researchers continue to dispute the effectiveness of the filters.
Filters have presented their own dangers. Studies have shown at least one brand of cigarettes contained asbestos filters. Kent cigarette filters were comprised of as much as 25% asbestos. These cigarettes were sold in the United States between 1952 and 1956, with up to half a million packs sold each day. Although Kent is the only brand confirmed to have contained asbestos, it is possible other cigarette brands contained the mineral.
04. Other Risk Factors
Other Mesothelioma Risk Factors
In addition to the risk factors listed above, the following factors have been noted in a handful of studies as potential risk factors for mesothelioma. These require additional research before causation can be confirmed.
Erionite, a naturally-occurring material often found in volcanic ash, has been noted for mesothelioma risk. The mineral contains fibers with a chemical formula similar to asbestos. Evidence shows an especially strong connection in regions where erionite exposure occurs in the natural environment, such as Turkey.
Some malignant mesothelioma patients have an unclear history of asbestos exposure. A few studies have cited radiation exposure as a possible cause in some cases. Although radiation therapy is a potential secondary factor for mesothelioma, there are limited reports that support this connection.
The simian virus 40 (SV40) has been linked to mesothelioma in a few cases. The virus stems from contaminated polio vaccines administered to around 30 million Americans between 1955 and 1963. Studies have shown a correlation between those who have the virus and development of mesothelioma, though further investigation is needed.
High aspect ratio nanoparticles (HARNs) are suggestively linked with mesothelioma. HARNs are nanoparticles with a length many times longer than their width. These particles have been proven harmful to human health. Like other non-asbestos causes of mesothelioma, evidence is lacking and requires more research.
05. Prevention of Mesothelioma
Prevention of Mesothelioma
Avoiding asbestos exposure is the most effective way to prevent mesothelioma. However, asbestos is not yet banned in the United States. In an effort to protect public health, the Environmental Protection Agency (EPA) has put asbestos regulations in place.
Although progress is being made, past uses of asbestos continue to pose a health risk. Professional removal of asbestos-containing products is essential to disease prevention.
If asbestos exposure is suspected, individuals should speak with their healthcare team and monitor for any symptoms of mesothelioma, such as shortness of breath, weight loss and chest pain. However, it is difficult to identify exposure because mesothelioma symptoms manifest decades after exposure occurs. Monitoring for symptoms enables early intervention, a key factor in improving life expectancy.