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Mesothelioma Diagnosis

The symptoms of mesothelioma often are the same as those of other diseases. This may make mesothelioma hard to diagnose. In particular, pleural effusion (fluid build-up in the chest cavity) may be found in several other diseases including lung cancer, heart failure and pneumonia. Early and precise diagnosis is important to successful mesothelioma treatment. However, doctors often are unsure if a person has mesothelioma, even after chest fluid has been removed and tested.

Experience Counts

If you have been exposed to asbestos and have symptoms, try to see a doctor who has experience in mesothelioma. If you have been diagnosed with mesothelioma, it is important that a doctor experienced in mesothelioma reviews your tests. Because doctors at MD Anderson focus on mesothelioma and see many patients with the disease, they are among the most skilled and experienced in the nation.

Mesothelioma Diagnosis

If you have symptoms that may signal mesothelioma, your doctor will examine you and ask you questions about your health; your lifestyle, including smoking and drinking habits; and your exposure to asbestos. One or more of the following tests may be used to find out if you have mesothelioma and if it has spread. These tests also may be used to find out if treatment is working.

Needle biopsy or drainage of lung fluid

Lung function test

Imaging tests, which may include:

  • CT or CAT (computed axial tomography) scans
  • MRI (magnetic resonance imaging) scans
  • PET (positron emission tomography) scans
  • Chest X-ray

Thoracoscopic surgical biopsy: A small incision (cut) is made in the chest. A tiny tube with a camera on the end is inserted, and a small amount of tissue is removed and looked at under a microscope.


Mesothelioma Staging

If you are diagnosed with mesothelioma, your doctor will determine the stage of the disease. Staging is a way of classifying cancer by how much disease is in the body and where it has spread when it is diagnosed. Staging helps the doctor plan the best way to treat the cancer. Surgery often is needed to stage mesothelioma. Once the staging classification is determined, it stays the same even if treatment works or the cancer spreads. 

Mesothelioma Stages

(source: National Cancer Institute)

Stage Ia: Tumor is in the outer layer of pleura (parietal pleura). It is not in the pleura covering the lung (visceral pleura).

Stage Ib: Tumor is in the parietal and the visceral pleura.

Stage II: Tumor has spread into the lung or diaphragm (the thin muscle that separates the chest from the abdomen).

Stage III: Tumor has spread into one of the following:

  • Pericardium (sac around the heart)
  • One area of the chest wall
  • Lymph glands within the chest

Stage IV: Tumor has spread to one or more of the following:

  • Multiple areas of the chest wall
  • Across the diaphragm or through the pericardium
  • Other organs such as the heart, windpipe, esophagus, liver
  • The opposite lung

Clinical Trials

MD Anderson patients have access to clinical trials offering promising new treatments that cannot be found anywhere else.

Knowledge Center

Find the latest news and information about mesothelioma in our Knowledge Center, including blog posts, articles, videos, news releases and more.