3 Facts About Mesothelial Cells — and What to Know About Mesothelioma
Blue is the official color of Mesothelioma Awareness Day, recognized annually on September 26. (Photo: Unsplash)
Why are mesothelial cells important? What exposures are linked to mesothelioma? How is it diagnosed? We answer these questions and more.
For any patient newly diagnosed, please talk to your physician about all of the options: surgery, chemotherapy, radiation therapy, but also clinical trials because they may open the door for new treatments that are not being thought about or discussed.
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.
What Are the Risk Factors for Mesothelioma?
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.
“Asbestos exposure is the most important risk factor associated with the development of mesothelioma,” noted radiation oncologist Rupesh Kotecha, M.D., in our podcast episode A Frank Conversation About Mesothelioma.
"Asbestos is actually the commercial name for a group of chemical minerals, and it’s used in a variety of industries," he said. "So, whenever we see a patient diagnosed with mesothelioma, we inquire through their history about any exposures, especially occupational exposures to any of these variety of industries [where asbestos may have been used]."
Dr. Kotecha added that there is a “latency period” of about 20 to 40 years from initial asbestos exposure to possible development of cancer.
Did You Know?
In March 2024, the U.S. Environmental Protection Agency announced a final rule to prohibit ongoing uses of chrysotile asbestos. It’s the only known form of asbestos used in (or imported to) the U.S. The ban helps advance President Biden’s Cancer Moonshot goals to end cancer as we know it. Read more about the EPA’s final rule.
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.
Signs, Symptoms & Diagnosis
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:
- Find information about mesothelioma, including testing, different treatment options to help you make informed decisions, and how to cope.
- Connect with our Cancer Support Helpline by phone or online. Our experienced Helpline staff are here to offer free navigation for cancer patients or their loved ones.
- Create a personal network site where you can document your journey and receive support from friends and family along the way.
- Find a supportive and caring CSC location near you. CSC and Gilda's Club locations offer a variety of professional led programs, including support groups and educational workshops, all at no cost to anyone impacted by a cancer diagnosis.
Help Raise Awareness
September 26 is Mesothelioma Awareness Day. Learn about the history of the awareness day and find out how you can show your support.
Don’t Forget Self-Advocacy
In addition to finding support, self-advocacy can play a key role in your care, whether you’re navigating a mesothelioma diagnosis or survivorship.
“Being your own advocate plays a vital role in your journey, even as a survivor,” notes Tamron, a mesothelioma survivor. “I’m more aware of what’s going on in my body and not afraid to ask questions or verbalize my concerns to my medical team.”
Editor's Note: This blog was originally published in 2022 and has been updated.
Support is vital. I couldn’t stress enough the importance of supporting your loved ones while they are battling mesothelioma.