Mesothelioma

What is it?

Mesothelioma is an uncommon cancer of the mesothelium, the thin lining that covers the organs.^4,5,1 It usually starts in the lining of the lungs and chest (pleura).^4,2,5 Less often it starts in the lining of the belly (peritoneum), and rarely around the heart or in the testicles.^2,5

The main cause is breathing in asbestos fibres over a long time; about 7 or 8 in 10 people with it have been exposed to asbestos.^6,7 Asbestos was used in buildings for decades before many countries banned it.⁶ You may have been exposed to asbestos if you work, or used to work, in building as an electrician, carpenter, plumber, heating and ventilation engineer, or construction or demolition worker.⁶ Living with someone who works near asbestos also raises the risk.⁸ It can take 15 to 60 years after exposure for the cancer to appear, and some people get it with no known risk factor.^6,8

The first signs

The signs depend on where the cancer is.² In the lining of the lungs it can cause:²

• chest pain and shortness of breath;²
• a cough that does not go away, or a hoarse voice;²
• a high temperature and heavy sweating at night;²
• feeling very tired, losing your appetite or losing weight without trying;²
• fingernails that curve over the fingertips (clubbing).²

In the lining of the belly it can cause belly pain or swelling, feeling or being sick, and diarrhoea or constipation.²

How doctors find out

Your family doctor asks about your symptoms and your work history, may gently feel painful or swollen areas and listen to your lungs, and may arrange an X-ray of your chest or tummy.^2,9 It can be hard to tell mesothelioma apart from lung cancer.¹ A lung specialist, or a gut specialist for belly symptoms, may arrange a CT, ultrasound or PET-CT scan and drain some fluid from the chest or belly through a small tube to check it for cancer cells.^2,9 Through a small cut, a thin camera can look inside, and a tiny piece of the lining can be taken (biopsy).⁹

Results can take several weeks.⁹ A specialist nurse is your main contact during and after treatment.⁹

Current treatment

For mesothelioma in the chest beyond the earliest stage, the standard is immunotherapy with nivolumab and ipilimumab or combination chemotherapy (with or without bevacizumab), with surgery or radiotherapy for some people and palliative care such as fluid drainage.Source: NCI PDQ

Will it get worse?

How serious it is depends on where it is in the body, how big it is, whether it has spread and your general health.⁴ It is often found when it is already advanced, which makes it harder to treat.¹ If the cancer is advanced, it might be very hard to treat and it may not be possible to cure it.³ The type of cancer cell also matters: the epithelioid type usually does better than the others.⁷

Medicines: what helps, and what to watch for

Immunotherapy is now the most common main treatment.³ Immunotherapy medicines such as nivolumab and ipilimumab help your immune system fight the cancer. You may have immunotherapy if you cannot have surgery.^10,3 Chemotherapy uses medicines to kill cancer cells; it can shrink the cancer and ease symptoms, or be given with surgery or radiotherapy to make them work better.³ A targeted medicine, bevacizumab, is sometimes added to chemotherapy.¹⁰

Good to know:

• Common side effects of chemotherapy are tiredness, feeling sick, a sore mouth, hair loss for a while, and numbness or tingling in the hands or feet;¹¹

Radiotherapy and draining fluid

Radiotherapy uses high-energy rays to kill cancer cells.³ It can be given after surgery to lower the chance of the cancer coming back, or to slow it down and ease symptoms.³

If fluid collects around a lung, doctors can drain it through a tube.¹⁰ To stop fluid building up again, doctors can put a chemical or drug into the space around the lung to make a scar between its layers (pleurodesis).¹⁰

Surgery, for some people

Surgery is rarely used, because it is hard to remove all of the cancer.³ It may be an option if the cancer is found early, or to ease symptoms.³ The surgeon may remove part of the lining of the chest and lung, or, in a bigger operation, a whole lung with the nearby linings.¹⁰ For cancer in the lining of the belly, surgery to remove the tumour may be followed by heated chemotherapy washed through the belly (HIPEC).¹⁰

Is there a cure?

If the cancer is advanced, it may not be possible to cure it. Treatment then aims to limit the cancer and its symptoms and help you live longer.³ Clinical trials are testing new treatments and new ways to use existing ones, and joining one may be an option.¹⁰

Median survival

About 12 to 19 months with treatment, in trials of mesothelioma of the lung liningSource: NCI PDQ, 2025

Measured in: First-line treatment of pleural mesothelioma, in three trials (605, 456 and 448 patients)

Sources

1. MedlinePlus: Mesothelioma
2. NHS: Mesothelioma – Symptoms
3. NHS: Mesothelioma – Treatment
4. NHS: Mesothelioma – What is mesothelioma?
5. NCI: What Is Mesothelioma?
6. NHS: Mesothelioma – Causes
7. NCI PDQ: Malignant Mesothelioma Treatment (PDQ) – Health Professional Version
8. NCI: Mesothelioma Causes and Risk Factors
9. NHS: Mesothelioma – Tests and next steps
10. NCI PDQ: Mesothelioma Treatment (PDQ) – Patient Version
11. NHS: Chemotherapy – Side effects