What is mesothelioma?

Mesothelioma is cancer of the mesothelium. Like most cancers, mesothelioma involves the abnormal dividing of cells of a particular part of the body — in this case, the mesothelium. Mesothelioma is so deadly because it remains dormant for many years and then begins to rapidly expand. The cancer then begins to invade and damage nearby tissue, including the vital organs.

What is the mesothelium?

Many of the internal organs of the body are protected by a membrane called the mesothelium. This membrane actually consists of two layers of cells. The inner layer surrounds the organs, and the second is a sac surrounding the inner layer. When organs within this membrane must move, expand or contract — such as the heart, lungs, bladder, and so on, they are able to do so because the mesothelium produces a lubricating fluid between the two layers.

Mesothelioma most often begins in the pleura or peritoneum. The pleura surrounds the lungs and covers the chest cavity. The peritoneum covers most of the organs in the abdominal cavity. Other mesothelium tissue is also vulnerable to mesothelioma. These include the pericardium that surrounds and protects the heart; the tunica vaginalis testic which surrounds the internal male reproductive organs; and the tunica serosa uteri which is the membrane covering the internal reproductive organs in women.

Who is at greatest risk to develop mesothelioma?

Mesothelioma has a very specific cause – exposure to asbestos. During the first half of the previous century, right up until the mid 1970s asbestos was an important material used to insulate buildings, machines, heavy equipment, and a broad range of commercial applications. Because it was plentiful and inexpensive to mine, asbestos was used in many building products such as home insulation, floor, ceiling and roof tiles. It was also used in commonly found commercial products such as brake linings and pipe insulation.

This meant that millions of people were coming in contact with asbestos on a daily basis. And since the effects of exposure to asbestos fibre often do not become apparent for 30 or 40 years after prolonged exposure, companies and health officials were slow to recognize the dangers of asbestos. As a result, shipyard workers, men and women working in asbestos mines and mills, workers producing asbestos products, workers in the heating and construction industries, and virtually all other tradespeople were exposed to asbestos fibres for extended periods of time.

Today it is understood that anyone working with or near asbestos has an increased risk of developing mesothelioma, so there are strictly controlled limits of exposure in the work place. But since the dormancy period of mesothelioma can often be 30 or 40 years, there are millions of workers who are at risk because of their exposure in the decades before the safety controls were put in place.

What are the symptoms of mesothelioma?

Pleural mesothelioma – cancer of the pleura or lung lining – causes shortness of breath or chronic coughing. Other symptoms of pleural mesothelioma may include chest pain, chronic coughing, shortness of breath, fatigue, wheezing, hoarseness, weight loss, or blood in the phlegm from the lungs when coughing.

Peritoneal mesothelioma affects the lining around the stomach and intestines and is usually just as dangerous. Symptoms of peritoneal mesothelioma include pain or swelling in the abdomen, weight loss, bowel obstruction, anemia, and fever.

Many of the symptoms of mesothelioma can easily be mistaken for allergies or a common cold. Mesothelioma is often discovered when patients think they have one of these other common illnesses.

How Serious is Mesothelioma?

By the time most infected people become aware they have mesothelioma, it is no longer dormant and becomes extremely aggressive. In its active phase, mesothelioma can travel quickly, and is almost impossible to stop. There are treatments used to keep the patient comfortable, but there is currently no cure for mesothelioma. As many as 75% of those who develop the disease will lose their life within one year. The remainder may last for up to an additional six months.

This makes it extremely important to detect the disease before it enters its active phase.

How is mesothelioma diagnosed?

Mesothelioma is often not diagnosed until it reaches an advanced stage. This is because of its long dormancy period, and because once it becomes active the initial symptoms are similar to much more comman and less dangerous sicknesses such as colds or the flu. If a patient has a history of exposure to asbestos, then a complete physical examination is advised. This would normally include x-rays of the chest or abdomen and lung function tests. It might also include a CT (or CAT) scan or an MRI. Both of these tests give detailed pictures of areas inside the body.

If these tests indicate the probability of mesothelioma, then it is necessary to perform a biopsy to confirm the diagnosis. Doing a biopsy involves an oncology specialist taking a small sample of affected tissue and examining it under a microscope for signs of malignancy. Depending on the location of the affected tissue, doing a biopsy can be a relatively traightforward procedure. It normally involves the insertion of a small instrument into the suspect cavity. These surgical devices have both viewing and sample taking capabilities. So the oncologist or surgeon can look at the cavity from the inside, and then take tissue samples from different areas.

If mesothelioma is discovered, the initial tests are followed up with what is called “staging”. This involves more tests to determine how far the disease has spread.

How is mesothelioma treated?

Standard treatments include the normal options available to cancer patients: surgery, radiation therapy, and chemotherapy. Sometimes, these treatments are combined. If the mesothelioma is discovered at an early enough stage these treatments can sometimes be effective.

Among the treatments that are used in order to reduce the effects of the disease are oxygen, postural drainage and pain killers. Many alternative treatment methods are also being tested, including attempts to strengthen the body’s immune system. Gene therapy is also being tested in an attempt to attack the problem at the DNA level. Other treatments being tried and tested include homeopathy, herbs and acupuncture. Unfortunately none of these have been found to be very effective once the disease reaches its aggressive stage.

As with all cancers, early detection is the best defense against mesothelioma. Anyone who has been exposed to asbestos should be alert for symptoms and contact a doctor immediately. Detecting mesothelioma at the earliest stage possible greatly increases the chances of beating the disease.

Mesothelioma is caused by asbestos exposure. Asbestos is a substance found naturally. It is made of strong flexible fibres. It was used extensively in industry because the fibres are not affected by heat or chemicals and a poor conductor of electricity. It is estimated that over 5,000 products have or had asbestos in them.

Of the six types of asbestos, only four are used commercially. These are chrysotile, crocidolite, amosite and anthrophyllite. Of these, crysotile or white asbestos accounts for 99% used in USA. In it natural state or well contained and maintained in products, asbestos do not pose a real hazard. It is when asbestos is broken down and fibres are released that there is concern.

Asbestos fibres are very thin and sharp. The fibre is 2,000 times thinner than a human hair. It measures under 0.3 microns or one millionth of a millimetre in diameter and five microns in length. It is not visible with the naked eye or through a microscope.
When released, the fibres remain in the atmosphere for a long time and can be carried great distances. When the fibres are inhaled, they stick to the lung tissue and are not expelled by breathing out or coughing. Some remain in the lungs, others gravitate into the pleural lining.

Asbestos exposure can lead to disease and develops over a long period of time. Asbestos related diseases are asbestosis, pleural plaques and lung cancers. The lung cancer can be either cancer of the lung itself or mesothelioma, a cancer of the lung lining. These cancers can take between 20 and 50 years to develop.
A recent article in a UK Newspaper highlighted the case of a Hospital Consultant who developed mesothelioma. He cannot recall any exposure to asbestos. It may well be that he was inadvertently exposed to asbestos without his knowledge i.e. such as living in the vicinity of a factory that leaked asbestos into the atmosphere.

Professor Peto has shown that new cases of mesothelioma will continue to increase in the early part of the twenty first century. He also said, “Every single person in the UK has asbestos in their lungs. It is the level of exposure that is important.”

We also know that people who has a history of asbestos exposure has a greater risk of lung cancer if they smoked. In a survey in 1992, 2602 individuals with lung cancer were interviewed. One in eight was exposed to asbestos and of these a third still smoked. A US study suggested that non-smokers exposed to asbestos have a five times greater risk of lung cancer. If they smoked, then the risk increased by a factor of 11. Smoking and asbestos exposure increases the risk of developing lung cancer to 52 times that of the general population.

At present no one knows how many lung cancers are due to asbestos exposure because of the long latency period and that cigarette smoking remains the major cause. Mesothelioma, however, is caused by asbestos exposure and this has been the basis of numerous high value legal claims.

As for the future, in the USA and Europe, asbestos related diseases will gradually increase to a peak. Of concern, however, are areas of conflict. In the Middle East, when a building was bombed, or when numerous buildings were bombed during the invasion of Iraq, do we have any idea how much asbestos was released into the atmosphere?

We are, however, certain that during the 9/11 disaster, asbestos fibres were released. When the Twin Tower collapsed, there were 400 tons of asbestos in the structure. The toxic cloud that hung over Manhattan, contained high level of asbestos. It is estimated that over 100,000 people suffered asbestos exposure. The greatest exposure was amongst first responders. Deborah Reeve was the first to die from asbestos related disease after 9/11. She was a first responder and paramedic. She died in March 2005 from mesothelioma. This concerned experts because mesothelioma takes a very long time to develop. They concluded that her exposure must have been excessive.

A study result showed that 70% of recovery and rescue workers who were active during and after the World Trade Centre collapse had some form of respiratory problem. A six year follow up study showed that sufferers with respiratory problems continue to have the same ailments.
“In the six years since the attacks,” Nadler said, “We have accumulated a mountain of evidence that thousands of those exposed are suffering from chronic respiratory disease and, increasingly, a variety of rare cancers.”

Hopefully, as experts predict, within the next few years asbestos related diseases will peak and the annual new cases will drop. If not, could it be a sleeping dragon about to wake up?