Being diagnosed with pleural mesothelioma

You will usually see your family doctor (GP) first. They will examine you and arrange for tests. Depending on the results they may refer you to hospital to be assessed.

If the doctors suspect you have mesothelioma they will ask you if you could have been exposed to asbestos in the past. This may have been through your work or through someone in your family who worked with asbestos.

A number of tests are used to diagnose a pleural mesothelioma. The first test is usually a chest x-ray. You may have a CT scan. If you have a build-up of fluid between the two layers of the pleura, a doctor may drain the fluid. This will then be checked for cancer cells. You will usually also have samples (biopsies) taken from your pleura to check for cancer cells. This can be done under a local anaesthetic, while you are awake, or, under a general anaesthetic, while you are asleep.

How pleural mesothelioma is diagnosed

Usually, you begin by seeing your family doctor (GP). They will examine you and may arrange for you to have some blood tests and x-rays. Your GP should urgently refer you for a chest x-ray if you have a history of asbestos exposure, and any of the following symptoms:

  • cough
  • fatigue
  • shortness of breath
  • chest pain
  • weight loss
  • loss of appetite.

Depending on the results of any tests and x-rays, your GP may refer you to hospital for further tests and specialist advice and treatment.

At the hospital, the specialist will ask you about your general health and any previous medical problems before they examine you.

You may be asked questions about any possible exposure to asbestos in your past, such as during jobs you’ve had or at places you’ve worked. This is called your occupational history. You may also be asked if someone in your family, a parent for example, worked with asbestos. Don’t worry if you can’t remember all of the details at first. You can let your doctor know later about anything you remember.

Tests for pleural mesothelioma

Pleural mesothelioma often starts as tiny lumps (nodules) in the pleura. These may not show up on scans or x-rays until they’re quite large. You may need to have a number of different tests before your doctors can make an accurate diagnosis. Tests you may have include:

Chest x-ray

A chest x-ray checks for any abnormalities in your lungs, such as thickening of the pleura or fluid around the lungs. There can be other causes of these problems apart from mesothelioma.

CT (computerised tomography) scan

A CT scan takes a series of x-rays, which build up a three-dimensional picture of the inside of the body. The scan takes 10–30 minutes and is painless. It uses a small amount of radiation, which is very unlikely to harm you and will not harm anyone you come into contact with. You will be asked not to eat or drink for at least four hours before the scan.

CT scan
CT scan

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You may be given a drink or injection of a dye, which allows particular areas to be seen more clearly. This may make you feel hot all over for a few minutes. It’s important to let your doctor know if you are allergic to iodine or have asthma, because you could have a more serious reaction to the injection.

You’ll probably be able to go home as soon as the scan is over.

Drainage of fluid from the pleura (pleural aspiration)

Mesothelioma cells can irritate the pleura and cause a pocket of fluid to develop. This is called a pleural effusion. Your doctor may take a sample of this fluid to send to the laboratory as mesothelioma cells are sometimes present. They will use a local anaesthetic to numb the area. A needle is then inserted through the skin into the fluid and some fluid is removed. You will have an ultrasound scan while the procedure is being carried out. This helps the doctor guide the needle to the place where the fluid is.

Pleural biopsy

A biopsy is usually needed to help the doctors diagnose pleural mesothelioma. It involves taking a sample of tissue from the thickened pleura and, occasionally, from the lymph nodes in the middle of the chest.

Your doctor may take a biopsy in different ways:

CT or ultrasound guided biopsy

A local anaesthetic is used to numb the area. Your doctor will then pass a special type of needle through the skin into the thickened area. An ultrasound or CT scanner will be used to help them guide the needle into the right place. The needle has a tip that can cut out a sample of tissue.


This allows the doctors to look at the pleura and other structures around the lungs. The doctor can take biopsies, if required.

You’ll be given either a general anaesthetic or a local anaesthetic with a sedative to make you drowsy. A small cut is made in the chest wall and the doctor puts a thin tube with a light and camera at the end (thoracoscope) into your chest. An ultrasound scan may be used to guide the thoracoscope to the thickened area of pleura. Your doctor can then take a biopsy of the pleura.

Sometimes doctors use a video camera with the thoracoscope. This is called video-assisted thoracoscopy (VATS) and it can help doctors get a better view of the area surrounding the lung.


If your doctor drains off fluid during any of these tests or procedures, they may also do a procedure called pleurodesis to try to prevent the fluid from returning. They will put sterile talcum powder through the tube in your chest and into the pleural space. This helps stop the fluid from building up again.


Very occasionally, your doctor may arrange for you to have a mediastinoscopy. This test allows the doctor to look at the area at the centre of your chest (mediastinum) and the lymph nodes closest to the lungs. You may have this test if your doctors think the mesothelioma has spread to the lymph nodes in the middle of the chest. It is done under a general anaesthetic and you will have a short stay in hospital.

A small cut is made in the skin at the base of your neck, and a thin flexible tube is passed into your chest. The tube has a light and camera at the end (mediastinoscope), and can magnify the areas it looks at. The doctor can see any abnormal areas, and may also take samples of the cells and lymph nodes (biopsies) to examine under a microscope.


Having a biopsy can be uncomfortable but shouldn’t be painful. If you have any pain during or after the procedure, let your doctor or nurse know.

Once a biopsy has been taken, it’s sent to the laboratory and examined by a pathologist (a doctor who advises on the type and spread of cancer).

Sometimes, even after taking a biopsy, the doctors may still not be sure of the diagnosis. This is because pleural mesothelioma can be very difficult to tell apart from some other illnesses. In this situation, the biopsy samples may be sent to other laboratories to confirm the diagnosis. Some of your tests may need to be repeated or you may be referred to another hospital for a second opinion.

Waiting for test results

Waiting for test results can be a difficult time. It may take from a few days to a couple of weeks for the results of your tests to be ready. You may find it helpful to talk with your partner, family or a close friend. Your specialist nurse or one of the organisations listed on our database, can also provide support. You can also talk things over with one of our cancer support specialists on 0808 808 00 00.

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