Asbestos and Mesothelioma

Most people who develop mesothelioma have worked in jobs in which they breathed in asbestos fibers. The latency period, or the time that elapses between first exposure and diagnosis, may last 20 to 50 years after a person is first exposed to asbestos.

This type of cancer affects the pleural membranes in the body. These membranes line the chest and abdominal cavities. As many as four in five cases of malignant mesothelioma affect the membranes in the chest.

Cancer that develops in the lining of the lungs and chest cavities is called pleural mesothelioma. Doctors refer to cancer that forms on the abdominal lining as peritoneal mesothelioma.

Mesothelioma affects between 2,000 and 3,000 people a year in the United States. Several treatments and therapies exist, but there is no known cure. Once symptoms appear, the disease can quickly turn fatal.

Asbestos fibers are microscopic. When people breathe them in, the fibers travel to the very ends of small air passages in the lungs. From there, the fibers can reach the pleural membranes of the chest cavity. If they are swallowed, they can end up in the stomach or other internal organs and eventually reach the membranes lining the abdominal cavity.

Once asbestos fibers reach the membranes, they cause inflammation and scarring. This can trigger changes in a person’s DNA and cause uncontrolled cell growth, which can lead to cancer, including mesothelioma.

Asbestos is the name for six different minerals that occur naturally in the environment. Not everyone who is exposed to asbestos will develop mesothelioma.

People who have worked in jobs with high amounts of exposure to asbestos for over a year or more are at the highest risk of developing the cancer. But just a few days exposure is enough to cause mesothelioma, according to the Occupational Safety and Health Administration.

“There is no ‘safe’ level of asbestos exposure for any type of asbestos fiber,” the agency said. “Every occupational exposure to asbestos can cause injury of disease; every occupational exposure to asbestos contributes to the risk of getting an asbestos related disease.”

People who were diagnosed can file a mesothelioma lawsuit against companies responsible for their asbestos exposure. Family members who have lost a loved one to the cancer can file wrongful death claims.

While mesothelioma may not develop until decades after asbestos exposure, it is not a slow growing cancer. It may take years for asbestos fibers to cause the actual inflammation that breeds uncontrolled cell growth. But once that happens, mesothelioma grows aggressively, within months to years.

This can give patients a very narrow window to seek early treatment, and patients may not be aware of the cancer growing inside them.

Mesothelioma can be hard to diagnose. And it may be difficult for doctors to tell mesothelioma apart from lung cancer at first. That means it may not be diagnosed until it’s in an advanced stage when it’s more difficult to treat. If you have worked around asbestos in the past, even decades ago, you should let your doctor know.

Diagnosis begins with your doctor reviewing your medical history and conducting a physical exam. Your doctor may also rely on blood tests to look for evidence of the disease. People with mesothelioma often have higher levels of certain substances in their blood. But a blood test alone cannot diagnose the disease.

If your doctor suspects mesothelioma, he or she may order digital imaging, such as CT or MRI scans. Depending on where in your body mesothelioma is suspected, the scan may focus on your lungs, heart or other parts of your body.

If these tests suggest the possibility of mesothelioma, the doctor may order a biopsy. This involves removing cells from areas that show abnormal growth inside the body. The samples will be reviewed under a microscope to look for evidence of the disease. Biopsies are the only way to accurately diagnose mesothelioma.

There are different ways doctors may conduct a biopsy. They may remove fluid they suspect built up because of mesothelioma, or they may use long needles to remove pieces of tumors they found in earlier tests.

A doctor may also use an endoscope, which is a thin tube with a light, a camera lens and surgical instruments attached to the end. It can be snaked through the body to look at possible tumors and remove pieces of them for testing. Or the doctor may surgically remove a tumor for testing.

Four types of treatment are standard for mesothelioma. Some may be used in combination with others to improve the chances of survival.

Research into new therapies is also underway. If you have been diagnosed with mesothelioma, you may want to talk with your doctor about the pros and cons of taking part in a clinical trial. Most trials require that you have not already begun standard treatment before joining a trial.

Average life expectancy from the time a person is diagnosed varies with age and overall health. It can be as little as one to five years for people who are older than 60 at the time of their diagnosis, according to a 2012 study in the Journal of Cellular Physiology.

The American Cancer Society uses a five-year relative survival rate to gauge average life expectancy after being diagnosed with mesothelioma. It compares people at different stages of the disease with those in the general population. Then, it calculates how likely each is to live for another five years.

For instance, if a particular stage shows an 18 percent five-year survival rate, then a person with that stage of mesothelioma is 18 percent as likely to live another five years as someone without the disease.

These numbers are not absolute. They can vary based on age, overall health, how well mesothelioma responds to treatment and other factors. As treatments improve, the rate of survival may also improve.