Overview

Mesothelioma is a cancer that starts as a growth of cells in the mesothelium. The mesothelium is a thin layer of tissue that covers many internal organs.

Mesothelioma is pronounced me-zoe-thee-lee-O-muh. It most often happens in the tissue around the lungs. This is called pleural mesothelioma. Mesothelioma also can happen in the tissues in the belly, around the heart and around the testicles.

Mesothelioma, which is sometimes called malignant mesothelioma, is a fast-growing and deadly form of cancer. There are mesothelioma treatments. But for many people with mesothelioma, there is no cure.

Symptoms

Signs and symptoms of mesothelioma depend on where the cancer starts.

Pleural mesothelioma affects the tissue around the lungs. Symptoms may include:

  • Chest pain.
  • Painful coughing.
  • Shortness of breath.
  • Lumps under the skin on the chest.
  • Tiredness.
  • Weight loss without trying.

Peritoneal mesothelioma affects tissue in the belly. Symptoms may include:

  • Belly pain.
  • Belly swelling.
  • Nausea.
  • Tiredness.
  • Weight loss without trying.

Other types of mesothelioma are very rare. Not as much is known about these other types.

Pericardial mesothelioma affects tissue around the heart. It may cause trouble breathing and chest pains.

Mesothelioma of tunica vaginalis affects tissue around the testicles. It may first appear as swelling or a mass on a testicle.

When to see a doctor

Make an appointment with a doctor or other healthcare professional if you have any symptoms that worry you.

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Causes

It's not always clear what causes mesothelioma. Experts believe that being around asbestos causes many mesotheliomas. But not everyone with mesothelioma has been around asbestos. Exactly what causes the cancer may not be known.

Mesothelioma is a cancer that starts as a growth of cells in the mesothelium. The mesothelium is a thin layer of tissue that covers many internal organs.

Mesothelioma happens when cells in the mesothelium develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time.

In cancer cells, the DNA changes give other instructions. The DNA changes tell the cancer cells to make more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells.

The cancer cells might form a mass called a tumor. The tumor can grow to invade and destroy healthy body tissue. In time, cancer cells can break away and spread to other parts of the body. When cancer spreads, it's called metastatic cancer.

Risk factors

Being around asbestos is the biggest risk factor for mesothelioma. Asbestos is a natural mineral. Asbestos fibers are strong, and they resist heat. This makes them useful in many ways. Asbestos gets used in insulation, brakes, shingles, flooring and many other products.

Mining asbestos or removing asbestos insulation breaks up the mineral. This may create dust. If people breathe in or swallow the dust, the asbestos fibers settle in the lungs or in the stomach. This may lead to mesothelioma.

Experts don't know the exact way asbestos causes mesothelioma. It can take 15 to 40 years or more to get mesothelioma after being exposed to asbestos.

Most people who have been around asbestos don't get mesothelioma. So other factors may be involved. For instance, it could run in families, or some other condition could raise the risk.

Factors that may raise the risk of mesothelioma include:

  • Being around asbestos. If you've been directly exposed to asbestos fibers at work or at home, your risk of mesothelioma is increased.
  • Living with someone who works with asbestos. People who work with asbestos may carry the fibers home on their skin and clothing. Over many years, these fibers can put others in the home at risk of mesothelioma.
  • A family history of mesothelioma. If your parent, sibling or child has mesothelioma, you may have a higher risk of this disease.
  • Radiation therapy to the chest. If you had radiation therapy to your chest for cancer, you might have a higher risk of mesothelioma.

Complications

As pleural mesothelioma spreads in the chest, it puts pressure on the structures in that area. This can cause complications such as:

  • Trouble breathing.
  • Chest pain.
  • Trouble swallowing.
  • Pain caused by pressure on the nerves and spinal cord.
  • Buildup of fluid in the chest, called pleural effusion. The fluid can press on the nearby lung and make breathing hard.

Prevention

Reducing your exposure to asbestos may lower your risk of mesothelioma.

Find out whether you work with asbestos

Most people with mesothelioma were around the asbestos fibers at work. Workers who may be around asbestos fibers include:

  • Asbestos miners.
  • Electricians.
  • Plumbers.
  • Pipefitters.
  • Insulators.
  • Shipyard workers.
  • Demolition workers.
  • Brake mechanics.
  • Selected military personnel.
  • Home remodelers.

Ask your employer whether you have a risk of asbestos exposure on the job.

Follow your employer's safety rules

Follow all safety rules in your workplace. Wear protective gear. You also may need to change out of your work clothes and wash with soap and water before eating or going home. Talk to your healthcare professional about other ways you can protect yourself from asbestos.

Be safe around asbestos in your home

Older homes and buildings may have asbestos. In many cases, it's better to leave the asbestos in place rather than trying to remove it. Breaking up asbestos may release fibers in the air. Then you could inhale them.

Talk with experts trained to find asbestos in the home. These experts may test the air in your home to see whether the asbestos is a risk to your health. Don't try to remove asbestos from your home. Hire an expert.

Dec. 05, 2024

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