Causes of Mesothelioma

What Causes Mesothelioma?

What causes mesothelioma? For many cancers, figuring out the cause for an individual cancer can be very challenging. Why does a non-smoker get lung cancer and a smoker does not? Why do people with very healthy diets sometimes get stomach or colon cancer? It’s very difficult to explain, but mesothelioma is often the exception to the rule.

The medical experts tell us that mesothelioma is almost always caused by asbestos. In fact, mesothelioma is often called the “asbestos caused cancer.” This means that if you were diagnosed with mesothelioma you were likely exposed to asbestos. If fact, many people diagnosed with this cancer have been exposed to asbestos at multiple times from multiple sources throughout their lives.

Other Causes

Other than asbestos, there are a few other things that are believed to cause mesothelioma cancer:

• Erionite
• Radiation Therapy
• Simian Virus 40

Few People Get Mesothelioma

This does not mean, however, that all people exposed to asbestos will eventually be diagnosed with mesothelioma. In fact, the opposite is true – most people exposed to asbestos will never be diagnosed with mesothelioma. It is estimated that millions of people have been exposed to this carcinogenic mineral, but only about 2,000 people per year out of these millions will ever be diagnosed with the asbestos caused cancer.

Clearly there is something else going on that causes some people to get this diagnosis, while others do not. So why do some people get diagnosed with mesothelioma, while the vast majority of people who were also exposed to asbestos, do not?

Scientists have been trying to answer two questions for years:

1. Why does mesothelioma occur in people many decades after the person was exposed to asbestos?
2. Why do most people exposed to asbestos never get mesothelioma?

In fact, the answers to these two questions may be related and involve what this carcinogenic mineral does in the human body.

How Asbestos Causes Mesothelioma

Asbestos is a naturally occurring mineral that is made of billions of needle like fibers. These fibers are resistant to heat and corrosion, and because they are fibers, they can be woven into other products. In fact, the fibers are so small that they are microscopic and millions can fit on the head of a pin.

It is believed that the size and shape of these fibers is what makes asbestos so dangerous. It is thought to work like this – tiny airborne fibers become inhaled or swallowed. Because they are so sharp and small they become embedded in different areas of the body. Somehow they are either trapped or moved to the mesothelial layers of the body, the thin layer of lubricating tissue that surrounds most of the body’s organs. There, it is believed, they create chronic inflammation. Over time this inflammation may lead to mesothelioma in some people.

Find Out More About Asbestos

Mesothelioma and the Immune System

Microscopic view of asbestos fibers

But, why does it cause mesothelioma in some people and not in others? Some scientists believe that the immune system plays a role in the cause of mesothelioma. One theory is that the immune system, when it is working properly, may be able to stop the creation of cancer. In fact, the immune system has a number of specialized cells which “patrol” the body and find and consume bacteria, viruses, and cancer cells. But, in some people that immune surveillance may not be working as well as it should. This could be because of another disease process, poor diet, or perhaps even stress. Whatever the cause, once the body’s immune system is suppressed and not functioning as it should, the theory is that the asbestos fibers and the chronic inflammation may, over time, result in cancer.

If this is true it would explain several intriguing observations: 1) some mesothelioma patients like Paul Kraus, Ruth Phillips, and others who use immune boosting approaches as part of their care often experience a benefit of some kind and may outlive their prognosis by years or decades; 2) other theorized causes of mesothelioma such as radiation therapy and SV40 can affect the immune system.

While asbestos is the leading cause of mesothelioma, some doctors have suggested that radiation therapy (treatment for another cancer) or a virus called SV40 may also cause or contribute to mesothelioma.

Radiation Therapy and Mesothelioma

Radiation therapy uses ionizing radiation to kill cancer cells. Like chemotherapy, radiation therapy is considered a cytotoxic (cell killing) modality. Wherever the beam is pointed, cells will be killed – both healthy cells and cancer cells. While radiation therapy may cause mesothelioma directly by turning healthy mesothelial cells into mesothelioma cells, another theory is that the radiation simply suppresses a patient’s immune system and once the patient’s immune system is suppressed the last barrier to cancer may have fallen.

SV40 and Mesothelioma

SV40 stands for Simian Virus 40. It is a virus found in some mesothelioma cancers as well as brain cancers, bone cancers and lymphomas. SV40 is a monkey virus that was released into the human population by the polio vaccines. Both the original starting materials (seed stocks) and the growth mediums used kidney cells from monkeys (African Green and Rhesus). These kidney cells were full of monkey viruses so when the vaccine was “harvested” many other extraneous viruses were captured as well. Simian Virus 40 was the 40th one found. According to early researchers like Dr. Bernice Eddy, SV40 caused tumors to grow in laboratory animals.

Obviously, the role of a cancer causing monkey virus from vaccines is a hotly debated topic. Nonetheless, SV40 is considered one of the most carcinogenic viruses known to man and some scientists believe that asbestos is the underlying cause of mesothelioma, but SV40 could play a co-carcinogenic role in some patients.

Is Asbestos Causing Mesothelioma Today?

While there is no comprehensive asbestos ban in the United States, asbestos was voluntarily taken out of most products by the late 1970’s and early 1980’s. Nonetheless, older houses and buildings still contain asbestos in joint compound (in walls), floor tiles, acoustic ceilings, roof shingles, and many other building products. Asbestos may also be found in late model cars in brakes, transmissions and clutches. Many products manufactured in other countries and imported into the United States may also contain asbestos. There is no policing or testing of these products. In fact, when an independent cancer organization tested children’s toys imported from China, they found asbestos in at least one product. Therefore, it is possible that asbestos can still be causing mesothelioma today.

However, because of the long latency period, most people diagnosed today were exposed to asbestos decades ago. If trends continue, the frequency of mesothelioma should decline over time. Nonetheless, because asbestos can be found in so many older products and structures it is best to remain vigilant. If you think there is asbestos near you, call in an expert.

Learn More About Mesothelioma

Find out more about the causes of mesothelioma and read about the longest-living survivor, Paul Kraus, in our free book, “Surviving Mesothelioma and Other Cancers: A Patients’ Guide.” Get the book express delivered to your door for free today!

Next: Symptoms of Mesothelioma

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