Malignant Mesothelioma Symptoms, Tests, Prognosis, and Stages (PDQ®)–Patient Version

General Information About Malignant Mesothelioma

Key Points

  • Malignant mesothelioma is a disease in which malignant (cancer) cells form in the lining of the chest or abdomen.
  • Being exposed to asbestos can affect the risk of malignant mesothelioma.
  • Signs and symptoms of malignant mesothelioma include shortness of breath and pain under the rib cage.
  • Tests that examine the inside of the chest and abdomen are used to detect (find) and diagnose malignant mesothelioma.
  • Certain factors affect prognosis (chance of recovery) and treatment options.

Malignant mesothelioma is a disease in which malignant (cancer) cells form in the lining of the chest or abdomen.

Malignant mesothelioma is a disease in which malignant (cancer) cells are found in the pleura (the thin layer of tissue that lines the chest cavity and covers the lungs) or the peritoneum (the thin layer of tissue that lines the abdomen and covers most of the organs in the abdomen). Malignant mesothelioma may also form in the heart or testicles, but this is rare.

EnlargeMalignant mesothelioma; drawing shows parts of the body where malignant mesothelioma may form, including the lungs, heart, pleura, abdominal cavity, and testicles.
Malignant mesothelioma forms in the thin layer of tissue that covers the lung, chest wall, abdomen, heart, or testicles.

Being exposed to asbestos can affect the risk of malignant mesothelioma.

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. Talk to your doctor if you think you may be at risk.

Most people with malignant mesothelioma have worked or lived in places where they inhaled or swallowed asbestos. After being exposed to asbestos, it usually takes a long time for malignant mesothelioma to form. Living with a person who works near asbestos is also a risk factor for malignant mesothelioma.

Signs and symptoms of malignant mesothelioma include shortness of breath and pain under the rib cage.

Sometimes the cancer causes fluid to collect in the chest or in the abdomen. Signs and symptoms may be caused by the fluid, malignant mesothelioma, or other conditions. Check with your doctor if you have any of the following:

  • Trouble breathing.
  • Cough.
  • Pain under the rib cage.
  • Pain or swelling in the abdomen.
  • Lumps in the abdomen.
  • Constipation.
  • Problems with blood clots (clots form when they shouldn’t).
  • Weight loss for no known reason.
  • Feeling very tired.

Tests that examine the inside of the chest and abdomen are used to detect (find) and diagnose malignant mesothelioma.

Sometimes it is hard to tell the difference between malignant mesothelioma in the chest and lung cancer.

The following tests and procedures may be used to diagnose malignant mesothelioma in the chest or peritoneum:

  • Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits, exposure to asbestos, and past illnesses and treatments will also be taken.
  • Chest x-ray : An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
    EnlargeChest x-ray; drawing shows the patient standing with her back to the x-ray machine.  X-rays are used to take pictures of organs and bones of the chest.  X-rays pass through the patient onto film.
    X-ray of the chest. X-rays are used to take pictures of organs and bones of the chest. X-rays pass through the patient onto film.
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of the chest and abdomen, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • Biopsy : The removal of cells or tissues from the pleura or peritoneum so they can be viewed under a microscope by a pathologist to check for signs of cancer.

    Procedures used to collect the cells or tissues include the following:

    • Fine-needle (FNA) aspiration biopsy of the lung: The removal of tissue or fluid using a thin needle. An imaging procedure is used to locate the abnormal tissue or fluid in the lung. A small incision may be made in the skin where the biopsy needle is inserted into the abnormal tissue or fluid, and a sample is removed.
      EnlargeFine-needle aspiration biopsy of the lung; drawing shows a patient lying on a table that slides through the computed tomography (CT) machine with an x-ray picture of a cross-section of the lung on a monitor above the patient. Drawing also shows a doctor using the x-ray picture to help place the biopsy needle through the chest wall and into the area of abnormal lung tissue. Inset shows a side view of the chest cavity and lungs with the biopsy needle inserted into the area of abnormal tissue.
      Fine-needle aspiration biopsy of the lung. The patient lies on a table that slides through the computed tomography (CT) machine, which takes x-ray pictures of the inside of the body. The x-ray pictures help the doctor see where the abnormal tissue is in the lung. A biopsy needle is inserted through the chest wall and into the area of abnormal lung tissue. A small piece of tissue is removed through the needle and checked under the microscope for signs of cancer.
    • Thoracoscopy : An incision (cut) is made between two ribs and a thoracoscope (a thin, tube-like instrument with a light and a lens for viewing) is inserted into the chest.
    • Thoracotomy : An incision (cut) is made between two ribs to check inside the chest for signs of disease.
    • Peritoneoscopy: An incision (cut) is made in the abdominal wall and a peritoneoscope (a thin, tube-like instrument with a light and a lens for viewing) is inserted into the abdomen.
    • Open biopsy : A procedure in which an incision (cut) is made through the skin to expose and remove tissues to check for signs of disease.

    The following tests may be done on the cells and tissue samples that are taken:

    • Cytologic exam: An exam of cells under a microscope to check for anything abnormal. For mesothelioma, fluid is taken from the chest or from the abdomen. A pathologist checks the fluid for signs of cancer.
    • Immunohistochemistry : A test that uses antibodies to check for certain antigens in a sample of tissue. The antibody is usually linked to a radioactive substance or a dye that causes the tissue to light up under a microscope. This type of test may be used to tell the difference between different types of cancer.
    • Electron microscopy : A laboratory test in which cells in a sample of tissue are viewed under a high-powered microscope to look for certain changes in the cells. An electron microscope shows tiny details better than other types of microscopes.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

  • The stage of the cancer.
  • The size of the tumor.
  • Whether the tumor can be removed completely by surgery.
  • The amount of fluid in the chest or abdomen.
  • The patient's age.
  • The patient's activity level.
  • The patient's general health, including lung and heart health.
  • The type of mesothelioma cells and how they look under a microscope.
  • The number of white blood cells and how much hemoglobin is in the blood.
  • Whether the patient is male or female.
  • Whether the cancer has just been diagnosed or has recurred (come back).

Stages of Malignant Mesothelioma

Key Points

  • After malignant mesothelioma has been diagnosed, tests are done to find out if cancer cells have spread to other parts of the body.
  • There are three ways that cancer spreads in the body.
  • Cancer may spread from where it began to other parts of the body.
  • The following stages are used for malignant mesothelioma of the lung:
    • Stage I
    • Stage II
    • Stage III
    • Stage IV

After malignant mesothelioma has been diagnosed, tests are done to find out if cancer cells have spread to other parts of the body.

The process used to find out if cancer has spread outside the pleura or peritoneum is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know whether the cancer has spread in order to plan treatment.

The following tests and procedures may be used in the staging process:

  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of the chest and abdomen, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  • Endoscopic ultrasound (EUS): A procedure in which an endoscope is inserted into the body. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. This procedure is also called endosonography. EUS may be used to guide fine-needle aspiration (FNA) biopsy of the lung, lymph nodes, or other areas.
    EnlargeEndoscopic ultrasound-guided fine-needle aspiration biopsy; drawing shows an endoscope with an ultrasound probe and biopsy needle inserted through the mouth and into the esophagus. Drawing also shows lymph nodes near the esophagus and cancer in one lung. Inset shows the ultrasound probe locating the lymph nodes with cancer and the biopsy needle removing tissue from one of the lymph nodes near the esophagus.
    Endoscopic ultrasound-guided fine-needle aspiration biopsy. An endoscope that has an ultrasound probe and a biopsy needle is inserted through the mouth and into the esophagus. The probe bounces sound waves off body tissues to make echoes that form a sonogram (computer picture) of the lymph nodes near the esophagus. The sonogram helps the doctor see where to place the biopsy needle to remove tissue from the lymph nodes. This tissue is checked under a microscope for signs of cancer.
  • Laparoscopy : A surgical procedure to look at the organs inside the abdomen to check for signs of disease. Small incisions (cuts) are made in the wall of the abdomen and a laparoscope (a thin, lighted tube) is inserted into one of the incisions. Other instruments may be inserted through the same or other incisions to perform procedures such as taking tissue samples to be checked under a microscope for signs of disease.
  • Lymph node biopsy : The removal of all or part of a lymph node. A pathologist views the tissue under a microscope to look for cancer cells.
  • Mediastinoscopy : A surgical procedure to look at the organs, tissues, and lymph nodes between the lungs for abnormal areas. An incision (cut) is made at the top of the breastbone and a mediastinoscope is inserted into the chest. A mediastinoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue or lymph node samples, which are checked under a microscope for signs of cancer.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

  • Tissue. The cancer spreads from where it began by growing into nearby areas.
  • Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
  • Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

  • Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
  • Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if malignant mesothelioma spreads to the brain, the cancer cells in the brain are actually malignant mesothelioma cells. The disease is metastatic malignant mesothelioma, not brain cancer.

Many cancer deaths are caused when cancer moves from the original tumor and spreads to other tissues and organs. This is called metastatic cancer. This animation shows how cancer cells travel from the place in the body where they first formed to other parts of the body.

The following stages are used for malignant mesothelioma of the lung:

Stage I

Stage I is divided into stages IA and IB:

  • In stage IA, cancer is found in the inside lining of the chest wall on one side of the chest. On the same side of the chest, cancer may also be found in one or more of the following:
    • The thin layer of tissue that covers the lung.
    • The thin layer of tissue that covers the organs between the lungs.
    • The thin layer of tissue that covers the top of the diaphragm.
  • In stage IB, cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. On the same side of the chest, cancer has also spread into one or more of the following:
    • Diaphragm.
    • Lung tissue.
    • Tissue between the ribs and the inside lining of the chest wall.
    • Fat in the area between the lungs.
    • Soft tissues of the chest wall.
    • Sac around the heart.

Stage II

In stage II, cancer is found in the inside lining of the chest wall on one side of the chest. On the same side of the chest, cancer may also be found in one or more of the following:

  • The thin layer of tissue that covers the lung.
  • The thin layer of tissue that covers the organs between the lungs.
  • The thin layer of tissue that covers the top of the diaphragm.

Cancer has spread to lymph nodes along the center of the chest on the same side of the chest as the tumor.

or

Cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. On the same side of the chest, cancer has also spread into one or both of the following:

  • Diaphragm.
  • Lung tissue.

Cancer has spread to lymph nodes along the center of the chest on the same side of the chest as the tumor.

Stage III

Stage III is divided into stages IIIA and IIIB.

  • In stage IIIA, cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. On the same side of the chest, cancer has also spread into one or more of the following:
    • Tissue between the ribs and the inside lining of the chest wall.
    • Fat in the area between the lungs.
    • Soft tissues of the chest wall.
    • Sac around the heart.

    Cancer has spread to lymph nodes along the center of the chest on the same side of the chest as the tumor.

  • In stage IIIB, cancer is found in the inside lining of the chest wall, and may also be found in the thin layers of tissue that cover the lung, the organs between the lungs, and/or the top of the diaphragm on one side of the chest. On the same side of the chest, cancer may have also spread into one or more of the following:
    • Diaphragm.
    • Lung tissue.
    • Tissue between the ribs and the inside lining of the chest wall.
    • Fat in the area between the lungs.
    • Soft tissues of the chest wall.
    • Sac around the heart.

    Cancer has spread to lymph nodes above the collarbone on either side of the chest or cancer has spread to lymph nodes along the center of the chest on the opposite side of the chest as the tumor.

    or

    Cancer is found in the inside lining of the chest wall, and in each of the thin layers of tissue that cover the lung, the organs between the lungs, and the top of the diaphragm on one side of the chest. Cancer has also spread to one or more of the following:

    • The chest wall and may be found in the rib.
    • Through the diaphragm into the peritoneum.
    • The tissue lining the chest on the opposite side of the body as the tumor.
    • The organs in the area between the lungs (esophagus, trachea, thymus, blood vessels).
    • The spine.
    • Through the sac around the heart or into the heart muscle.

    Cancer may have spread to lymph nodes.

Stage IV

In stage IV, cancer has spread to the tissue covering the lung or the lung on the opposite side of the chest, peritoneum, bones, liver, lymph nodes outside the chest, or to other parts of the body.

Recurrent Malignant Mesothelioma

Recurrent malignant mesothelioma is cancer that has recurred (come back) after it has been treated. The cancer may come back in the chest or abdomen or in other parts of the body.

  • Updated: July 30, 2018

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