Mesothelioma

Mesothelioma is a rare cancer that can form in the lining around your lungs (pleura) or abdominal organs (peritoneum). Rarely, mesothelioma affects the sac around your heart (pericardium) or lining around your testicles (tunica vaginalis).

Mesothelioma starts in your mesothelium, a type of tissue that makes up a lining that surrounds and protects certain organs. It often creates multiple tumors that can sometimes combine into a sheet over the affected organs, making it hard to treat.

Types of mesothelioma

The most common type of mesothelioma is pleural mesothelioma, which affects the lining of your lungs. Other types include:

• Peritoneal mesothelioma. This affects the lining of your abdominal and pelvic cavities. It’s the second most common type of mesothelioma.
• Pericardial mesothelioma. This affects the sac around your heart. It’s extremely rare.
• Mesothelioma of the tunica vaginalis testis (paratesticular mesothelioma). This affects the lining around your testicles. It’s also extremely rare.

Sometimes, solitary fibrous tumors are called “benign mesothelioma,” but they’re not really related to cancerous (malignant) mesothelioma.

You might also hear mesothelioma described as epithelioid, sarcomatoid or biphasic (a mix of both). This describes the shape and other characteristics of the cancerous cells. The type of mesothelioma you have might affect your treatment options and prognosis (outlook).

Symptoms of mesothelioma

Symptoms of mesothelioma depend on where it is in your body. They include:

• Fever
• Night sweats
• Fatigue
• Unintended weight loss
• Chest or abdominal pain
• Respiratory symptoms, like worsening shortness of breath (dyspnea), cough and difficulty swallowing (dysphagia)
• Digestive symptoms, like diarrhea, loss of appetite, nausea and vomiting
• Cardiovascular symptoms, like low blood pressure and abnormal heart rhythms
• Swelling, lumps or pain in your scrotum or groin

Mesothelioma causes

Asbestos exposure is the most common cause of mesothelioma. Asbestos is a naturally occurring mineral once commonly used in many industries, including construction, shipbuilding and the automotive industry. It has needlelike fibers that can damage your tissues if you breathe them in or swallow them. Mesothelioma doesn’t show up right away — it can take decades for cancer to develop after asbestos exposure.

But developing cancer can depend on many factors — most people exposed to asbestos don’t get mesothelioma. And people with mesothelioma don’t always have a history of asbestos exposure.

Risk factors

Having a job that exposed you to asbestos is a risk factor for mesothelioma. These could include:

• Construction and building demolition
• Shipbuilding
• Mining
• Military service
• Milling
• Auto repair

Other risk factors include:

• Radiation exposure. This includes radiation treatments (especially to your chest) for a previous cancer or working at a job that exposes you to radiation.
• Exposure to erionite. Erionite, an asbestos-like mineral, was once used in road construction.
• Genetics. An inherited change in the BAP1 gene can make you more likely to get certain cancers, including mesothelioma.
• Biological sex. More males than females get mesothelioma.

Complications of mesothelioma

Mesothelioma can spread (metastasize) to other parts of your body. It can also cause fluid to build up around your lungs (pleural effusion) or heart (pericardial effusion) or in your abdomen (ascites).

How doctors diagnose mesothelioma

Based on your symptoms and health history, your provider might get the following tests to diagnose or rule out mesothelioma:

• Blood tests
• Lung function tests
• Imaging tests, including chest X-rays and CT scans
• PET (positron emission tomography) scans to determine if there are tumors in other parts of your body
• Draining fluid from your pleural or abdominal cavity (thoracentesis or paracentesis) to look for cancer cells (cytology)
• Biopsy

How is mesothelioma treated?

Typically, no single treatment can cure mesothelioma on its own. Treatment options for mesothelioma depend on the kind you have. Options could include:

• Surgery. Surgery could include extrapleural pneumonectomy (EPP), pleurectomy with decortication (which removes your pleura and the tumor), cytoreduction or pericardiectomy.
• Immunotherapy. These treatments train your immune system so it’s better able to identify and destroy cancer cells.
• Chemotherapy. Providers usually give chemotherapy drugs through an IV, which travels through your bloodstream to kill cancer cells. They apply some forms of chemotherapy to the tumor more directly, like hyperthermic intraperitoneal chemotherapy (HIPEC).
• Targeted therapies. You might have genetic changes in your tumor cells that targeted therapies can treat.
• Radiation therapy. Radiation uses high-energy X-rays to destroy cancer cells.
• Clinical trials. Your provider might recommend clinical trials of medications that researchers are still testing for effectiveness.
• Palliative care. Your provider may recommend palliative care to help you manage cancer symptoms and treatment side effects. Types of palliative care could include pain management and procedures to drain fluid from around your organs.

When should I see my healthcare provider?

Talk to your provider if you notice symptoms like shortness of breath, persistent cough or changes in your bathroom habits. It might seem scary to investigate your symptoms, but getting treated early is always better than waiting.

Can mesothelioma be prevented?

Cancer is rarely completely preventable. You can reduce your risk of mesothelioma by avoiding asbestos. Take precautions for proper handling and disposal if you have to work with it or around it.

If you had a job that exposed you to asbestos in the past, talk to your provider about whether they have recommendations for monitoring or screening for potential health issues.

What is the survival rate for mesothelioma?

Survival rates for mesothelioma depend on the kind you have. For example, the five-year relative survival rate for the most common type, pleural mesothelioma, is between 7% and 24%. In general, peritoneal mesothelioma survival rates are higher than those of other types.

Keep in mind that these numbers are based on people diagnosed at least five years ago. They may not reflect what you can expect with new treatments or other factors of your specific situation. Ask your provider what to expect.

Is mesothelioma 100% fatal?

No, mesothelioma isn’t fatal for everyone. But it’s an aggressive cancer that’s rarely caught in early stages, when it’s more treatable.