Malignant Mesothelioma: Diagnosis

If your healthcare provider thinks you might have malignant mesothelioma, certain exams and tests will be needed to know for sure. The process starts with your healthcare provider asking you questions. You'll be asked about your health history, your symptoms, risk factors, and family history of disease. A physical exam will be done. Based on the findings, your healthcare provider will decide what other tests are needed.

What tests might I need?

You may need 1 or more of these:

  • Imaging tests

  • Biopsy

  • Blood tests

Imaging tests

If you have symptoms of mesothelioma, you may need imaging tests. These can show if there's a tumor, where it is, and how big it is. But they can't tell if the tumor is mesothelioma.


Chest X-rays are often the first test done when a person has a cough that doesn’t go away or shortness of breath. X-rays of your chest can show fluid or other signs of cancer in the spaces around your lungs.

X-rays of your belly (abdomen) can help your healthcare provider see if there might be cancer there.

If a change is seen on an X-ray, other imaging tests might be done.

CT scan

A CT scan uses X-rays taken from many angles and a computer to make detailed 3-D pictures of the inside of your body. A CT scan shows much more detail than an X-ray. A contrast dye might be put into a vein in your hand or arm before or during the scan. The dye travels through your blood and helps get even more detailed images.


This test is an ultrasound of your heart. It might be done if your provider wants to check for fluid buildup around your heart.


Imaging tests might strongly suggest you have cancer. But a biopsy is the only way to know for sure.

To do a biopsy, your healthcare provider takes small bits of fluid or tissue (called samples) from the area that might be cancer. The samples are sent to a lab. There, a specialized healthcare provider (pathologist) looks at them under a microscope and tests for cancer cells.

Medicines are used to make you sleep and not feel pain during a biopsy.

There are different biopsy tests that might be done, such as:


This test takes a small piece of changed tissue in your chest.

A long, thin lighted tube with a tiny camera on the end (thoracoscope) is put in through a cut (incision) in the skin over your chest. It's slid into your chest to look at the tissue that appears different on the scan. The healthcare provider looks carefully at the lining of the inner part of your chest and your lung. Then tiny pieces of the tissue that looks different are taken out for testing.


This test takes a small sample from a tumor in your belly (abdomen).

The healthcare provider puts a narrow, lighted tube with a tiny camera on the end (laparoscope) through a cut in the skin over your belly to look at the tumor. The scope is used to look carefully at the lining of the inner part of your belly and over your intestines and other organs. Small pieces are removed from suspicious-looking areas so they can be tested for cancer.


For this test, your healthcare provider uses a long, thin tube called a bronchoscope. It goes into your mouth, down your windpipe, and into the main air passages of your lungs. Your provider uses the scope to look for changed tissues in your airways. A biopsy can be done through the bronchoscope.


This surgery involves making a large cut in your chest and between 2 ribs. It is done to remove a larger piece of tissue from the tumor or maybe the entire tumor. It may be done if other biopsies don't get enough tissue to make a clear diagnosis of mesothelioma.


In this surgery, your healthcare provider makes a larger cut in your belly. This is done to remove a larger piece of tissue from the tumor or the entire tumor. It might be done if other types of biopsies don't get enough tissue to be sure a change is mesothelioma.

Thoracentesis, pericardiocentesis, and paracentesis

These procedures are used to take out fluid for testing. Your healthcare provider uses a long, hollow needle and syringe to do this. The needle is put through your skin to remove fluid from your chest (thoracentesis), from the sac around your heart (pericardiocentesis), or from your belly (paracentesis).

It can be hard to diagnose mesothelioma by looking at fluid or tissue samples. This is because this cancer can look a lot like other kinds of cancer. Special lab tests are usually done to know if and what type of mesothelioma it is.

Blood tests

You may have blood tests to help diagnose mesothelioma. But not all providers agree that these tests are useful. Your healthcare provider may look for these substances in your blood:

  • Soluble mesothelin-related peptides (SMRPs)

  • Osteopontin

  • Fibulin-3

These blood tests alone can't diagnose mesothelioma. But high levels of these substances can make the diagnosis more likely.

Other blood tests can be used to get an idea of your overall health and how well certain organs are working.

Getting your test results

It usually takes several days for the results of your biopsy to come back. When your healthcare provider has your test results, they will contact you. Ask how you can expect to find out your biopsy results. Will it be a phone call or do you need to make an appointment?

Your provider will talk with you about other tests you may need if mesothelioma is found. Make sure you understand what the results are and what your next steps should be.

Online Medical Reviewer: Kimberly Stump-Sutliff RN MSN AOCNS
Online Medical Reviewer: L Renee Watson MSN RN
Online Medical Reviewer: Todd Gersten MD
Date Last Reviewed: 6/1/2021
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