mercredi 12 août 2015

all information about mesothelioma

Mesothelioma is a cancer caused by exposure to asbestos. Over time, many people have been unwittingly exposed to the deadly fibres as a result of their work, or by living alongside someone who works in an environment which contains asbestos.


Once the fibres are inhaled, or ingested, they can lodge themselves in internal body tissue where they cause
damage and may lead to asbestos-related diseases. Mesothelioma is possibly the most severe form of disease associated with asbestos.
It can take a long time for mesothelioma to develop – at least ten to fifteen years and sometimes even as many as forty years.

Can I make a claim?

For a while, employers were not aware of the dangers of asbestos, but it quickly became apparent that workers needed protecting. If an employer failed to provide adequate training or protection for their employees they can be held liable for compensation if a worker suffers an industrial disease such as mesothelioma.
If you would like more information about mesothelioma symptoms or any other aspect of the disease, including making a compensation claim, please call our lawyers FREE on 0800 0891331.
Thompsons Solicitors in Scotland has an excellent track record in tracing the liable parties, and their insurers, even if the firm has ceased trading. Contact us today using our online claim forms, or simply leave your details and we will call you back.

Types of mesothelioma

There are three different types of Mesothelioma: Pleural Mesothelioma, Peritoneal Mesothelioma and Pericardial Mesothelioma.
Pleural Mesothelioma is the most common type and is caused by inhaling asbestos fibres into the lungs. A tumour then forms on the lining (pleura) of the lungs, which makes breathing difficult and painful.
Peritoneal Mesothelioma is less common and is caused by inhaled fibres which are coughed up out of the lungs and then swallowed down into the stomach. A tumour then develops on the lining of the abdomen (peritoneum) which prevents it from working properly to lubricate the organs inside the abdomen.
Pericardial Mesothelioma is the least common form of the disease. Patients suffering from this type of mesothelioma develop a tumour on the membranes lining the heart and this prevents the heart from working properly to pump blood around the body.

Mesothelioma in the chest (pleural mesothelioma)

Pleural mesothelioma starts in the pleura. The pleura is the two layers of thin membrane that surround the lungs and line the chest wall. The inner layer is attached to the lungs and the outer layer lines the chest wall and diaphragm. Between the two layers is the pleural cavity. This cavity is almost empty. The two layers of pleura slide against each other. They're moist so that lungs can move smoothly against the chest wall as you breathe.

Sometimes mesothelioma can spread into the area around the heart (pericardium).

Mesothelioma in the abdomen (peritoneal mesothelioma)

Peritoneal mesothelioma starts in the peritoneum. This is the sheet of tissue covering and lining the internal organs in the abdomen. This sheet helps to protect the organs and allows them to move around within the abdomen. The peritoneum makes a fluid that helps to keep the abdominal organs moving freely and smoothly as we move around.

Causes of mesothelioma

Asbestos exposure

Mesothelioma is very strongly linked with asbestos exposure. Almost everyone diagnosed with mesothelioma was exposed to asbestos.
Asbestos is a mineral rock made up of masses of tiny fibres. For many decades, asbestos was mined and widely used in building materials and for insulation, fireproofing and sound absorption. It was used to insulate buildings, ships, car parts, household appliances and power stations.
There are three types of asbestos - blue, brown and white. All are linked to mesothelioma although blue and brown are more commomly linked. The health hazards of asbestos have become clear in recent decades.
Asbestos has been banned in Australia since 2004 and it is now illegal here to store, mine, import, sell, install or reuse any products containing asbestos. Any asbestos products already in place are allowed. However, great care needs to be taken if anything known to contain asbestos is to be disturbed or pulled down. There are strict regulations associated with removal and disposal of asbestos for areas greater than 10m2. See our ‘Services and information' section.
Most people are at low risk of asbestos exposure and mesothelioma. People who've been exposed to asbestos in their jobs are at greater risk. Such jobs include:
  • mining or milling asbestos
  • manufacture and repair of goods using raw asbestos fibres, such as brake linings
  • use of products containing asbestos, like in building and construction,
  • heating, shipyards, power stations, boiler making, gas fittings and plumbing
  • alteration, repair or demolition of buildings or other structures containing asbestos.
It may take over 20 years after exposure for any disease caused by asbestos to become evident (it can take up to and over 50 years).
However, most workers exposed to asbestos won't develop an asbestos-related disease.

Why is asbestos dangerous?

When asbestos is disturbed, it forms a dust made up of tiny fibres. This can easily be breathed in and cause serious health problems, notably:
  • pleural plaque
  • asbestosis
  • diffuse pleural thickening
  • benign pleural effusion
  • lung cancer
  • mesothelioma.
When asbestos is disturbed it sends out fibres into the air that can be inhaled by anyone nearby. Workers in mining and construction, plumbers, carpenters and auto mechanics have been at risk of exposure to asbestos.
It can also affect family members of workers who brought home asbestos fibres on their clothing and shoes from their work site.
It is not clear how asbestos fibres get into the peritoneal cavity. It is unlikely that they come through the wall of the gut. However, they may come in through the diaphragm. When asbestos fibres are taken into the body, cells react in an abnormal way. This may result in inflammation and scarring causing pleural plaque or diffuse pleural thickening. Or it may alter the DNA of the cells and result in the cells becoming malignant.

How common is mesothelioma?

Mesothelioma is a rare type of cancer but it is affecting more people. Australia has one of the highest rates of mesothelioma in the world. This is related to the high rate of asbestos use in mining, construction, manufacturing and home renovations over many years. In 2007 (the most recent data available), nearly 600 people were diagnosed with mesothelioma in Australia. Of these new cases, 81% were men.
In Victoria about 160 people are diagnosed each year. These figures are likely to change. Experts believe the number of people diagnosed with asbestos-related diseases will not peak until 2020. Since 1980 there have been about 13,000 new cases of mesothelioma in Australia.

Symptoms

In its early stages mesothelioma (pleural and peritoneal) may not cause many symptoms. It is only later, when the cancer moves into the underlying tissues or causes fluid to leak into the cavity in the chest or abdomen, that symptoms appear.

Symptoms of pleural mesothelioma

The cancer causes cells in the pleura to produce fluid, called a pleural effusion. The fluid builds up between the two layers of pleura and presses on the lungs. This can cause:
  • shortness of breath
  • a persistent dry cough
  • pain, which is often described as a heaviness or dull aching in the shoulder, arm, chest wall and upper abdomen. Some people describe it as like having pulled a muscle; others describe it as a sharp, stabbing or even ‘burning' pain
  • difficulty swallowing, a hoarse voice or coughing up sputum or blood - these are rare symptoms.
As the cancer progresses, it can grow into the lung, lymph nodes, chest wall, ribs, brain and liver, causing other symptoms.

Symptoms of peritoneal mesothelioma

Mesothelioma in the peritoneum (‘peritoneal mesothelioma') causes:
  • abdominal pain
  • swollen abdomen
  • poor appetite
  • nausea and vomiting
  • fever
  • bowel or urinary problems.

Symptoms of advanced stage disease

Advanced stage cancer usually means cancer that has spread from where it began to other parts of the body. You may hear doctors call this ‘metastatic', ‘progressive' or ‘secondary' cancer. Most people diagnosed with mesothelioma have advanced cancer, although at the time they are diagnosed they may not yet have symptoms of advanced cancer.
As well as the symptoms described above, other symptoms that may appear at this stage include:
  • severe weight loss
  • fatigue
  • fever
  • sweating
  • confusion due to chemical imbalances in the body or spread of the
  • cancer to the brain
  • lumps under the skin.
All symptoms discussed in this section can be caused by other, less serious diseases. However, if you or someone close to you has any of them (especially if you know you have been exposed to asbestos) you should see your doctor. If necessary they can do further tests to find the cause of your problems. 
If you've been exposed to asbestos in the past and develop shortness of breath, chest pain or other symptoms (pain, cough, weight loss), see your GP and ask for a referral for a chest x-ray or other tests they think may be necessary. Tell the doctor you've been exposed to asbestos. If any abnormalities show up on your x-ray or you remain unwell you should see a respiratory specialist.

Mesothelioma Causes

Contact with asbestos is the leading cause of mesothelioma cancer, as nearly every patient diagnosed with this aggressive cancer came in contact with it at some point. Mesothelioma caused by asbestos exposure commonly occurs occupationally, environmentally or as a result of secondhand exposure.
Mesothelioma — a cancer that most commonly attacks the lungs and abdomen — was profoundly rare until industrial and commercial companies expanded the use of asbestos during the 20th century. After spending decades investigating the disease and its causes, medical researchers identified one primary culprit: Exposure to asbestos.
Medical research studies gradually pointed to the fact that breathing in minuscule asbestos fibers starts a chain of physical and metabolic events that lead to the development of several types of cancers or an incurable breathing disorder called asbestosis.

In March 2009, the International Agency for Research on Cancer reconfirmed that asbestos exposure is the leading cause for mesothelioma and all forms of asbestos cause the disease.


What are the Most Common Mesothelioma Symptoms?

Asbestosis and mesothelioma symptoms, unfortunately, mirror many other types of lung-related diseases. Symptoms can be different based on the type of cancer and can be vague and mild even as the disease progresses into a later stage. Early signs can be so slight that they are mistaken as normal aches and pains or symptoms of other illnesses, making asbestos-related cancer hard to detect.

Early Mesothelioma Symptoms Are Hard to Detect

Many patients don't understand the early symptoms of mesothelioma. They only seek medical advice when symptoms intensify, which is why much of the mesothelioma research today involves finding better ways to secure an earlier diagnosis, when it can be treated more effectively. There is considerable support for early screening for those with prolonged, occupational exposure to asbestos.

Mesothelioma Symptoms Are Often Misdiagnosed

For physicians who are not trained to deal with these diseases, mesothelioma doesn't come to mind when trying to link warning signs to a disease. Consider, for instance, how often doctors hear that a patient is tired all the time. People with mesothelioma have been misdiagnosed initially with things like pneumonia, bronchial infection and COPD.
 

Pleural Mesothelioma Symptoms

Pleural mesothelioma is caused by inhaling asbestos fibers, which become trapped in the lining of the lungs, known as the pleura. These microscopic fibers cause irritation and inflammation in the pleura. This inflammation causes thickening in the layers of the pleura and the buildup of fluid around the lungs (pleural effusion). The buildup of fluid and thickening of the lining surrounding the lungs prevents the lung from fully expanding. This causes chest discomfort and painful breathing. 

Pleural Mesothelioma Symptoms (Stages 1 & 2)

Patients in the early stages of pleural mesothelioma do not exhibit many symptoms. Those that do show are not specific to the disease. Symptoms common in the early stages of this disease are:
  • Shortness of breath (dyspnea)
  • Chest pain
  • Persistent coughing
  • Pleural effusions (fluid buildup)
  • Fever
  • Fatigue
  • Weight loss
  • Body aches
These are similar to symptoms of various other disorders, such as pneumonia, common cold, asthma, influenza, and Chronic Obstructive Pulmonary Disease (COPD). Pleural effusions and inflammation in the lining of the lungs are the main source of discomfort associated with mesothelioma, but are also linked to pneumonia and COPD.
Up to 25 percent of patients have symptoms like dyspnea and chest pain for approximately 6 months before seeing a doctor.
Pleural thickening is another result of pleural mesothelioma that is common in other diseases. This is caused by the scarring of the pleura. It causes a loss of elasticity in the lungs, which is essential for the lung to expand for normal breathing.
Pleural thickening can also be caused by tuberculosis, pleurisy, and empyema (infection in the lung that causes a buildup of pus in the pleura). However, in mesothelioma, this is specifically caused by scarring of the pleura due to asbestos.

Pleural Mesothelioma Symptoms (Stages 3 & 4)

Late stages of pleural mesothelioma have more specific symptoms, but also include symptoms from the earlier stages. In stages 3 and 4, symptoms still include difficulty breathing, chest pains, and coughing, but these symptoms may be more severe. Symptoms specific to pleural mesothelioma begin to emerge in these stages. This is when most patients are diagnosed. These symptoms may include:
  • Fever and/or night sweats
  • Shortness of breath (dyspnea)
  • Painful breathing
  • Fatigue
  • Anemia
  • Persistent pain in the chest or rib region
  • Persistent coughing
  • Coughing up blood (hemoptysis)
  • Difficulty swallowing (dysphagia)
  • Pleural effusions
During these stages, treatment may be used to relieve pain and discomfort associated with various symptoms. For example, doctors may drain pleural effusions to reduce chest pain and make breathing easier.


Pericardial Mesothelioma Symptoms

Pericardial mesothelioma makes up less than 1 percent of mesothelioma cases, and the exact origin of the disease is unknown. Symptoms associated with pericardial mesothelioma are:
  • Chest pain
  • Pericardial thickening
  • Irregular heartbeats
  • Pericardial bleeding
  • Dyspnea (difficulty breathing)
  • Pericardial effusion (fluid buildup)
Misdiagnosis of pericardial mesothelioma is common because the symptoms associated with the cancer are so general. The most common misdiagnoses for pericardial mesothelioma are pericarditis (inflammation of the pericardium) and myocarditis (inflammation of the heart).


Symptoms of Mesothelioma

Presenting symptoms of pleural mesothelioma can be as nondescript as a chest pain, slight fatigue, or a shortness of breath during physical activity. Symptoms often mirror signs of less serious respiratory issues and are hardly unusual for a senior.
Pleural mesothelioma cancer may take decades to develop after exposure to asbestos, but it attacks quickly once taking hold. The microscopic asbestos fibers that are inhaled can lodge in the thin lining around the lungs and trigger physiological cellular changes that lead to this rare but aggressive cancer.
Many people with pleural mesothelioma are unaware of their own condition for months or even years because initial symptoms are often mistaken for less threatening illnesses. Any history of asbestos exposure, or even suspected asbestos exposure, should be discussed with a physician, who can refer a patient to a specialist right away. An early diagnosis is critical to survival because it can lead to more effective therapy options.

Symptoms Can Be Confusing

Most symptoms of pleural mesothelioma involve the respiratory system and often are misdiagnosed because most medical professionals rarely see this disease. It's estimated that more than 2,000 people in the United States are diagnosed annually with this cancer. By comparison, an estimated 150,000 Americans are diagnosed with lung cancer each year.
Initial symptoms of pleural mesothelioma often are confused with pneumonia or asthma or another respiratory ailment. Even a specialist will need considerable time — in addition to results of various, complex tests — to provide a definitive diagnosis.
According to a 2011 study of 221 pleural mesothelioma patients, many reported similar symptoms in the early stages, often before it was diagnosed.
They included:
  • 79 percent experienced shortness of breath
  • 64 percent suffered chest pain
  • 36 percent had a chronic cough
  • 90 percent presented with pleural effusions (excess fluid around lungs)
  • 30 percent experienced significant weight loss
If any of these symptoms appear, and there is a history of asbestos exposure, it is important to see a specialist.
Many patients diagnosed in stage I have no symptoms and the cancer is accidentally detected through routine X-ray or other tests. In this early stage, the tumor burden is relatively minimal and may not cause any noticeable symptoms. The two most common presenting symptoms of pleural mesothelioma are shortness of breath and chest pain. These symptoms usually develop as a result of pleural effusion or tumors pressing against the lung and chest wall, which can happen in in stages I through III.
In stage II, as tumors spread beyond the pleural lung lining and into the lung and diaphragm, pain may increase and may be felt in the shoulder or upper abdomen in addition to the chest. Difficulty breathing and coughing may arise or worse at this stage.
During stage III, tumors spread more thoroughly throughout the chest, placing pressure on the lungs and chest wall. These physical changes can lead to an increase in pain and difficulty breathing, dry cough, tightness in the chest, fatigue and weight loss.
By stage IV, tumors have spread throughout the chest and rarely spread to distant locations. The degree of tumor burden in the chest can severely worsen pulmonary symptoms like shortness of breath. Others symptoms may include lumps of tissue under the skin on the chest, pain in the lower back, fever and night sweats. Some patients experience a hoarse voice and difficulty swallowing. At this stage, patients often need help breathing and require continuous oxygen.

Recognizing Symptoms

Because a pleural mesothelioma diagnosis is often not made until after the cancer has spread, the prognosis can be grim. The process of recognizing the symptoms and turning them into a definitive diagnosis so treatment can begin usually involves multiple procedures with different medical professionals and often takes several months.
During the diagnostic process, a patient may see a pulmonologist, a radiologist, a pathologist and a surgeon, as well as an oncologist and a primary care physician. Patients might also then opt for a second opinion. Early symptoms could lead to imaging tests that include X-rays, an MRI, CT scans and PET scans. If one of the scans reveals an irregularity, a biopsy is needed to confirm the presence of mesothelioma. Although it can take 10 to 50 years after exposure to asbestos before cancer develops and symptoms appear, the survival time after symptoms are diagnosed can be short. The majority of patients are given a prognosis of six to 18 months to live.
Early diagnostic methods, more awareness and improved treatments have allowed some patients to live well beyond their initial prognosis. The most important thing is to find a specialist who understands the disease and understands all the intricacies and treatment options.
"It's important to have someone who is comfortable with the disease," said Hedy Kindler, M.D., director of the mesothelioma program at the University of Chicago Medical Center. "You need a quarterback who understands all the options."

  • Cassandro, R., Montrasio, S., & Espsito, V. (2008). Natural history of human pleural mesothelioma. In A. Baldi (Ed.), Mesothelioma from bench side to clinic (pp. 337-345). New York, NY: Nova Science Publishers, Inc.
  • Kindler, H (2012, February). University of Chicago Medical Center, Phone interview with Hedy Kindler, M.D.
  • Moore, A., Parker, J., Wiggins, J. (2008). Malignant Mesothelioma. Orphanet Journal of Rare Diseases. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2652430/?tool=pubmed
  • Alexander, R. (2011, October). University of Maryland. Phone interview with Richard Alexander, M.D.