About peritoneal mesothelioma

Mesothelioma is a type of cancer that starts from mesothelial cells. These cells line the surface of most of the internal organs and body cavities, creating a protective membrane called the mesothelium.

Some mesotheliomas form a mass (tumour), while others grow along the mesothelium and form a thick covering. In later stages, mesothelioma may spread (metastasise) to other parts of the body.

Learn more about:

• What is peritoneal mesothelioma?
• How mesothelioma affects the abdomen and pelvis
• What causes mesothelioma?
• How common is mesothelioma?
• What can I expect?
• Can I seek compensation?

What is peritoneal mesothelioma?

The mesothelium (protective membrane) that covers the organs and lines the walls of the abdomen and pelvis is called the peritoneum.

Mesothelioma that develops in the peritoneum is known as peritoneal mesothelioma. It is far less common than pleural mesothelioma (which is found around the lungs), and accounts for less than 5% of all mesotheliomas.

The peritoneum

There are 2 layers of thin tissue in the peritoneum. The inner layer (the visceral peritoneum) lines the surface of organs such as the bowel, liver and ovaries. The outer layer (the parietal peritoneum) lines the walls of the abdomen and pelvis.

Between the 2 layers of the peritoneum is the peritoneal cavity, which normally contains a very thin film of fluid. This fluid allows the 2 layers to slide over each other. In people with peritoneal mesothelioma, too much fluid often collects between the 2 layers in this cavity. This is called ascites or peritoneal effusion.

Other types of mesothelioma

• Pleural mesothelioma – The mesothelium (protective membrane) that covers each lung is called the pleura. Mesothelioma that develops in the pleura is called pleural mesothelioma, and accounts for about 95% of mesothelioma cases. Pleural mesothelioma is not the same as lung cancer – it is diagnosed and treated differently.
• Pericardial mesothelioma – In rare cases, mesothelioma can develop in the pericardium, which is the lining of the heart. This is called pericardial mesothelioma.
• Testicular mesothelioma – Even more rarely, mesothelioma can occur in the membrane that surrounds the testicles, known as the tunica vaginalis. This is called testicular mesothelioma.

For more on this, see Rare and less common cancers.

How mesothelioma affects the abdomen and pelvis

Peritoneal mesothelioma affects the peritoneum – the membrane that lines the walls and covers the organs of the abdomen and pelvis. These organs include the stomach, bowel, liver, kidneys and, in females, the uterus and ovaries.

The abdomen and pelvis

What causes mesothelioma?

Exposure to asbestos fibres or asbestos dust is the cause of most (9 out of 10) cases of mesothelioma. But in some cases there is no clear link to asbestos.

What is asbestos?

Asbestos is the name for a group of naturally occurring minerals that are resistant to high temperatures and humidity. Asbestos was used in many building products in Australia from the 1940s until 1987. Since 2004, Australia has banned asbestos being sold, reused and/or imported. Despite the ban, asbestos is still found in many older buildings, so special care needs to be taken when renovating. Asbestos has also been found in some products from overseas.

Highest risk groups

People who may have been exposed to asbestos at work include: builders, plumbers, gasfitters and electricians; metal-fitters, turners and toolmakers; boilermakers and welders; steelworkers; asbestos miners; asbestos cement manufacturing workers; insulators; automotive industry workers; mechanics; transport workers (especially waterside workers); telecommunications technicians; and textile workers.

People cleaning work clothes with asbestos fibres on them, or spending time in areas where asbestos has been disturbed during renovations or maintenance, can also develop mesothelioma.

It can take many years for mesothelioma to develop after a person is exposed to asbestos. It is often around 40 years after exposure, but may be 10–60 years. This is called the latency period or interval.

How common is mesothelioma?

Australia has one of the highest rates of mesothelioma in the world, with an estimated 900 Australians diagnosed each year. Men are 4 times more likely than women to be diagnosed with pleural mesothelioma. This is probably because asbestos exposure is more common in jobs that were traditionally done by men, such as building and plumbing.

Pleural mesothelioma makes up about 95% of mesothelioma cases. Peritoneal mesothelioma is less common and makes up less than 5% of cases. Mesothelioma is more common in people over the age of 65, but it can occur in younger people.

What can I expect?

The plan for what happens if you have mesothelioma can vary from person to person, but is usually as follows:

• Diagnosis and staging – You will have various tests to confirm a diagnosis of mesothelioma and work out how far it has progressed. The results will help you and your health professionals make decisions about treatment.
• Treatment – Depending on how advanced the mesothelioma is and other factors, treatment may achieve a longer period of disease control and improve quality of life.
• Managing symptoms – For many people, the main goal of treatment will be to manage symptoms and improve quality of life. Depending on how mesothelioma affects your health, you may have periods of relatively good health when symptoms are under control or less active. You may also have periods when symptoms need to be relieved with more intensive treatment.

Can I seek compensation?

People who develop mesothelioma due to asbestos exposure may be able to make a claim for compensation. It’s helpful to make notes and talk to family and friends about when and where you may have been exposed to asbestos.

It is important to get advice from an experienced lawyer as soon as possible after diagnosis, because a case for compensation must be started within your lifetime. Mesothelioma or asbestos support groups may be able to help you with more information about seeking compensation.

See Making a Claim to learn more about seeking compensation.

→ READ MORE: Peritoneal mesothelioma symptoms