3 Facts About Mesothelial Cells — and What to Know About Mesothelioma

August 31, 2023

Why are mesothelial cells important? What exposures are linked to mesothelioma? How is it diagnosed? We answer these questions and more.


Mesothelial cells surround the body’s internal organs. They also line the inside of our chest, abdomen, and the space around our heart. The mesothelial cells form a layer of tissue called the mesothelium.

But what's its purpose, exactly?

The mesothelium plays an important role in our bodies. Here are 3 things to know:

1. The mesothelium linings help protect our organs, much like a cushion.

2. The mesothelium allows our organs to move — another extraordinary and vital function. Thanks to the mesothelium, for example:

  • Your lungs move when you breathe.
  • Your heart moves when it beats.
  • The organs in your stomach move when you digest food.

3. The mesothelium has different names in different parts of our bodies. For example, the mesothelium that lines the heart is called the pericardium. In the chest, it’s called the pleura. In the abdomen, it’s called the peritoneum.


What Is Mesothelioma?

Even if you weren’t already familiar with mesothelial cells, chances are you’ve heard of mesothelioma from commercials and other advertisements about the disease. Malignant mesothelioma is a rare, fast-growing cancer that starts in mesothelial cells. 

If a cancerous tumor forms within the mesothelium, it could be 1 of 4 types of mesotheliomas:

  • Pleural mesotheliomas – These start in the chest. They are the most common kind, representing nearly 75% of all cases. This is not the same as lung cancer.
  • Peritoneal mesotheliomas – These begin in the abdomen or stomach area. They are less common, accounting for about 25% of all cases.
  • Pericardial mesotheliomas – These start in the covering around the heart. They are very rare.
  • Mesotheliomas of the tunica vaginalis – These start in the covering of the testicles. They are very rare.

Note: Some tumors of the mesothelium are not cancer. They are usually removed by surgery.

There is a strong relationship between mesothelioma and asbestos exposure, meaning people who have worked or lived around asbestos are at higher risk of developing the disease. Other risk factors for mesothelioma include exposure to:

  • Zeolites, which are minerals that are chemically related to asbestos
  • SV40 virus, found in polio vaccines given between 1955 and 1963 (this is still being studied)
  • Radiation

Non-exposure risk factors for developing mesothelioma include increasing age and a change in the BAP1 gene.

We can take steps to better protect ourselves and our loved ones from exposures linked to mesothelioma, including avoiding exposure to asbestos. Wearing protective gear and following other precautions may be necessary if working with asbestos material. 

Some homes built before 1980 contain asbestos in their building materials, such as the insulation. So, depending on when and how a home was manufactured, updates may be needed to abate asbestos from the home. 

The United States Environmental Protection Agency provides guidance on protecting your family from asbestos, including how to identify asbestos, what to do if your home has asbestos, and professionals who can help improve the health of your home.

CSC presents a Facebook Live "What You Need to Know About Mesothelioma" on September 27, 2022 at 1 p.m. ET
Watch our in-depth conversation about mesothelioma with Dr. Rupesh Kotecha, a radiation oncologist from the Miami Cancer Institute. The conversation addresses treatment options, coping with side effects, and support resources. 



Signs, Symptoms, & Diagnosis of Mesothelioma

Common symptoms of mesothelioma include trouble breathing, pain in the rib cage or stomach area, swelling or lumps in the abdomen, and unexpected or unintentional weight loss.

These symptoms make mesothelioma hard to diagnosis because it can look like lung cancer or other conditions that aren’t cancer.

To diagnose mesothelioma, doctors will often complete a physical exam and assessment of the patient’s health history. The most common next steps in diagnosis and care include a chest x-ray, a complete blood count test, and a biopsy. Biopsy methods can range from fine-needle aspiration — the use of a thin needle to remove some tissue or fluid from the lung — to surgeries like laparotomy or thoracotomy.




Mesothelioma Resources & Support

If you are living with mesothelioma or are a caregiver to someone with mesothelioma, we offer a variety of resources to help ease the burden of your journey:

Did You Know?

September 26 is Mesothelioma Awareness Day. Learn about the history of the awareness day and find out how you can show your support.