Malignant mesothelioma is a rare and serious cancer caused by exposure to asbestos. It takes 20 to 50 years to develop and occurs in the lining of the lungs, chest, abdomen and heart.

Types of Mesothelioma

Malignant mesothelioma is a cancer of the mesothelium caused by asbestos exposure. The mesothelium is a thin membrane that protects and lubricates different body cavities, such as the chest and abdominal cavities. Learn more about this rare disease in our free Mesothelioma Guide.

Where Does Mesothelioma Develop?

  • Pleural Mesothelioma Icon

    Pleural Mesothelioma

    Cancer of the mesothelium in the lungs is known as pleural mesothelioma. It accounts for 3 out of 4 mesothelioma diagnoses because most asbestos fibers are inhaled, lodging into the lining of the lungs.

  • Peritoneal Mesothelioma Icon

    Peritoneal Mesothelioma

    Cancer of the mesothelium surrounding the abdomen is known as peritoneal mesothelioma. It is caused by ingesting asbestos fibers and accounts for about 20 percent of all diagnoses.

  • Pericardial Mesothelioma Icon

    Pericardial Mesothelioma

    Cancer of the mesothelium surrounding the heart is known as pericardial mesothelioma. This is a rare form of mesothelioma and is not usually diagnosed while the patient is still alive.

Mesothelioma can also develop in the lining of the testicles. Testicular mesothelioma is extremely rare and occurs in less than 1 percent of mesothelioma cases.

Symptoms of Mesothelioma


  • Effusions (Fluid)
  • Weight Loss
  • Shortness of Breath
  • Persistent Dry Cough
  • Persistent Chest Pain
  • Difficulty Swallowing
  • General Fatigue


  • Abdominal Pain
  • Weight Loss
  • Nausea / Vomiting
  • Bowel Irregularity
  • General Fatigue
  • Seizures (10 percent of patients)
  • Ascites (Fluid)


  • Difficulty Breathing
  • Chest Pain
  • General Fatigue
  • Weight Loss
  • Irregular Heartbeat
  • Fever
  • Heart Murmurs

Mesothelioma Causes & Risk Factors


Malignant mesothelioma is almost exclusively tied to prolonged asbestos exposure. Asbestos is a naturally occurring mineral that became very popular in the 20th century due to its heat resistance and insulating properties. Asbestos has been used in a variety of products from building materials to car parts.

The mesothelium is a lining that protects certain internal organs and is made up of mesothelial cells. Asbestos fibers may be inhaled or ingested and lodge themselves in the mesothelium. These fibers are difficult for the body to expel.

In most cases, these fibers are inhaled and end up in the lining surrounding the lungs and chest, known as the pleura. In other cases, the fibers may be ingested and end up in the lining of the stomach and abdomen, known as the peritoneum.

In rare cases, asbestos fibers find their way to the pericardial lining surrounding the heart and cause pericardial mesothelioma. The causes of this type of mesothelioma are still being explored.

Over an extended time, these fibers can agitate and damage the mesothelial cells. This damage causes otherwise healthy cells to become abnormal and replicate constantly, which leads to the growth of tumors and the development of mesothelioma.

Risk Factors

Since asbestos was widely used in industrial and commercial products, a large number of individuals have been exposed to this toxic substance. People such as factory workers, shipbuilders, military veterans or insulation manufacturers who worked with asbestos while removing or installing it are at risk of developing mesothelioma.

Family members of those who worked with asbestos are also at risk of developing mesothelioma. Asbestos fibers and dust carried into the home on work clothes could have been inhaled by family members. This is referred to as “secondary exposure.”

Finding a Mesothelioma Specialist

Selecting a Top Doctor is Critical

Selecting a mesothelioma specialist is the most important decision a patient can make. A general oncologist (cancer doctor) simply does not have the experience dealing with mesothelioma that a specialist has.

Mesothelioma specialists are not as common as other doctors because of the extreme rarity of mesothelioma (2,000 to 3,000 cases every year). Use our free Doctor Match program to find a mesothelioma specialist near you. Treatment prescribed by a mesothelioma specialist can significantly extend a patient’s life.

Not every specialist treats each and every type of mesothelioma. Depending on the stage, type, location, severity and more, certain specialists are a better fit than others.

Diagnosing Mesothelioma

Many patients are diagnosed with mesothelioma after exhibiting a persistent cough or pneumonia-like symptoms. Because mesothelioma takes 20 to 50 years to develop, its symptoms often appear without warning. When a patient has persistent symptoms, doctors suggest imaging tests to look for any abnormalities or signs of cancer.

Medical imaging options include X-Rays, CT scans and PET scans. A doctor usually begins with an X-Ray to determine whether there are any irregularities in the patient. Following these imaging tests, a doctor may order a blood test for further evidence of the presence of mesothelioma. When cancer cells are present in the body, there are numerous proteins released that may be measured through a blood test.

To confirm a diagnosis, the doctor orders a surgical biopsy and carefully removes part of the tumor tissue.

Most mesothelioma biopsies are major surgeries and may require a multi-day hospital stay. The biopsy also determines cell type of the cancer, which can be epithelioid, sarcomatoid or biphasic. All of this testing provides mesothelioma specialists with the information they need about the cancer to treat it effectively.

The 4 Stages of Mesothelioma

Once doctors have a definitive diagnosis of malignant mesothelioma, they try to determine the current stage of the disease. Staging determines the cancer’s severity and also indicates which treatment options are available. Mesothelioma stages follow a system of assigning a number between 1 and 4 to the disease, with Stage 1 being the least severe and Stage 4 being the most progressed.

  • Stage 1 Mesothelioma Icon

    Stage 1

    Mesothelioma is localized to the point of origin. There is no lymph node involvement in this stage. Diagnoses at this stage are rare.

  • Stage 2 Mesothelioma Icon

    Stage 2

    Mesothelioma remains confined to the point of origin. Regional lymph nodes may be affected. Patients at this stage still have many treatment options, including aggressive surgery.

  • Stage 3 Mesothelioma Icon

    Stage 3

    Mesothelioma has spread beyond the point of origin. Additional lymph nodes are affected. Surgery may still be an option at this stage.

  • Stage 4 Mesothelioma Icon

    Stage 4

    Mesothelioma has spread to other organs and lymph nodes. Organ failure is possible at this stage. This stage has the fewest treatment options, so it is absolutely imperative to see a specialist.

Based on the stage of the patient’s disease, specialists either prescribe treatments to remove the cancer and extend life or simply focus on limiting patient discomfort. It should also be mentioned that there are several staging systems for mesothelioma, and a doctor might see different opportunities for treatment based on the system they follow. This is an important reason why patients should always consider getting a specialized second opinion.

Mesothelioma Treatment

Treatment isn’t one size fits all. Specialists choose from a variety of treatment options depending on the type of mesothelioma (pleural, peritoneal, or pericardial), the cell type and the personal medical history of the patient. For the best treatment, find a mesothelioma cancer center with experience in mesothelioma treatment and research.

  • Mesothelioma Surgery Icon


    Though typically only available in the first two stages, surgery is the only treatment option known to significantly extend life.

  • Mesothelioma Chemotherapy Icon


    Chemotherapy circulates medication through the bloodstream, which slows or kills additional cancer growth.

  • Mesothelioma Radiation Icon


    High levels of radiation targeted at the affected area may kill cancerous cells and stop the growth of new cells.

  • Mesothelioma Multimodal Treatment Icon


    A specialist combines a number of different treatment options to combat mesothelioma, such as surgery and chemotherapy.

  • Mesothelioma Clinical Trials Icon

    Clinical Trials

    There are many clinical studies being conducted to evaluate and develop new treatments. These clinical trials are an additional option to consider for patients and may lead to a future cure.

  • Mesothelioma Alternative Treatment Icon

    Alternative Treatment

    Some survivors credit alternative health options as instrumental in their recovery. Examples include yoga, meditation, and acupuncture.

Mesothelioma Prognosis

The word “prognosis” comes from the Greek word meaning “pre-knowledge.” Prognosis is tied to life expectancy and survival rates. There are a series of steps that patients can take to increase life expectancy and improve prognosis.

The prognosis estimates the likely path and behavior the cancer is expected to take and how a patient is affected by it in the future.

Ways to Improve Prognosis

  • 1
    Find a Mesothelioma Specialist – Seeing a specialist is the most important way to improve prognosis. Specialists have experience treating mesothelioma that general oncologists don’t have.
  • 2
    Get a Second Opinion – Always seek a second opinion before accepting a treatment plan. Second opinions may reveal more treatment options that lead to longer survival.
  • 3
    Explore Treatment Options – Patients should explore all their treatment options with their doctor and decide the best plan based on their diagnosis. Every diagnosis is different and certain treatments work better for certain patients.
  • 4
    Maintain a Healthy Lifestyle – Patients who maintain a healthy lifestyle are more resilient to aggressive treatment and are more capable of fighting the disease.
  • 5
    Enroll in Clinical Trials – Participating in a clinical trial can provide access to treatment methods not offered elsewhere. Talk to your specialist about clinical trials that may improve your prognosis.

Learn more about how these steps factor into a better life expectancy and how you can take control of your prognosis in our free Mesothelioma Survivors Guide.