Mesothelioma is a rare cancer that affects the tissue that lines the inside of your chest and abdomen, the space around your heart, and most organs.

This lining protects your organs by making a liquid that allows the organs to move easily. For example, it helps your lungs slip easily and painlessly against other organs and your chest wall when they move as you breath. This cancer causes the cells in this lining to grow out of control. Sometimes, the cancerous tissue can wrap around an organ, stopping it from working properly.

There are four forms of mesothelioma:

  • Malignant pleural mesothelioma affects the tissue that surrounds the lungs, known as pleura. This is the most common form of the condition.
  • Malignant peritoneal mesothelioma affects the tissues in the abdomen.
  • Malignant pericardial mesothelioma affects the tissues surrounding the heart.
  • Mesothelioma of tunica vaginalis affects the tissue surrounding the testicles.

The most common cause of this cancer is breathing in asbestos. Asbestos is a material that used to be popular for insulation and is still used in some products today.

Asbestos fibers are not visible to the naked eye. When inhaled, these fibers stick to the lung's linings. Over time, these fibers cause scarring and damage to the lungs, which can result in mesothelioma or other types of lung cancer.

People who have spent a long time with or had repeated exposure to asbestos have a greater chance of these fibers building up in their lungs.

See also emphysema, thymoma, sarcoidosis and mediastinal tumors for other diseases that affect the lungs.


Mesothelioma may not be seen until 20 to 30 years after the first exposure to asbestos. Symptoms of pleura malignant mesothelioma, the most common type, include:

  • Difficulty breathing, pain in the chest or both
  • Hoarseness
  • Difficulty swallowing
  • Coughing up of blood

If cancer cells are growing in the abdomen, you may notice an increase in your waist size or pain in that part of your body.

Unintended weight loss is a symptom associated with both pleura and peritoneal forms of the condition.

Symptoms for the other forms of mesothelioma are not as well known because those forms of the condition are rare.


Diagnosis of mesothelioma usually begins with a physical exam. During the exam, the doctor will pay special attention to the patient's symptoms as well as how much contact they have had with asbestos. After the exam, the doctor will conduct tests to determine the cancer's stage.

Chest X-rays and CT scans provide an image of what is going on inside the lungs and chest. These images can show if fluid has begun to build up in the chest or lungs and show if the cancer has spread to other areas of the body. CT scans can help determine the stage of cancer.

If fluid has begun to build up in the chest or lungs, the doctor may take a sample of the fluid to test it for lung cancer. When lung cancer is present, the body creates a substance, called an antigen, that tells the immune system to respond. High levels of this specific antigen, known as carcinoembryonic antigen (CEA), are a sign of lung cancer.

If mesothelioma or lung cancer is suspected, the doctor will take a biopsy, a small tissue sample using a needle. The sample will be studied under a microscope for signs of cancer.

  • Stage I - the cancer is limited to one area of the tissue lining.
  • Stage II - the cancer has spread past the lining of the chest to the diaphragm or to a lung.
  • Stage III - the cancer has spread to other organs and tissues within the chest, possibly to nearby lymph nodes.
  • Stage IV – this is advanced cancer that has spread more completely through the chest. The cancer may have also spread to other areas of the body, such as the brain, liver and lymph nodes.


Treatment for mesothelioma depends on where the cancer is, what stage it is and how healthy the person who has it is. Mesothelioma can grow quickly and be hard to treat. More than one kind of treatment may be used.

Radiation therapy and chemotherapy are common treatments. Surgery may be used in some cases.

Radiation therapy focuses an intense beam of energy, often an X-ray, onto the spot where the cancer is. This beam of energy can help reduce symptoms and slow the spread of the cancer.

Chemotherapy uses a mixture of medications to kill the cancer cells. Chemotherapy may be used to treat cancers that cannot be taken out by surgery or to help shrink the cancer before surgery. Sometimes the medicine is injected directly into the abdominal cavity. This helps protect normal, healthy cells from being damaged by the cancer-fighting medicine.

In some cases, when the condition is caught at an earlier stage, surgery may be possible to remove the cancer.

© 2000-2022 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
Want More Information?

Cedars-Sinai has a range of comprehensive treatment options.

Looking for a Physician?

Choose a doctor and schedule an appointment.

Need Help?


Available 7 days a week, 6 am - 9 pm PT

Need Help?


Looking for a Physician

Choose a doctor and schedule an appointment.