Key Takeaways
- Pleural plaques are benign (non-cancerous) collagen-based growths that form in the pleura — the tissue lining around the lungs, abdomen, or heart — as the body’s immune response to asbestos fibers. They are the most common bodily response to asbestos exposure.
- Pleural plaques are not cancerous and are not mesothelioma. While they can cause discomfort — including impaired breathing and chest pain — they do not pose the same serious health risks. There is no standard treatment beyond managing symptoms like pain.
- Whether pleural plaques can independently increase the risk of developing mesothelioma is debated. A 2013 study found that 17 patients with plaques later developed mesothelioma over several years — enough to suggest a statistical association.
- A 2020 study identified a regulatory gene called IL1B that appears to influence whether a patient develops pleural plaques or mesothelioma — but did not establish a causal link between plaques and cancer.
- The current scientific consensus is that genetics and immune function play a greater role in determining whether asbestos exposure leads to plaques or mesothelioma than the plaques themselves do.
- Understanding why some people develop benign plaques while others develop mesothelioma could unlock new therapeutic targets — the protective immune mechanisms in plaque-only patients may hold clues for future mesothelioma treatments.
What is a Pleural Plaque?
A pleural plaque is a collagen-based mass that develops in the pleura—the space around the lungs, abdomen, or heart—in response to ingested asbestos. Pleural plaques are the most common bodily response to asbestos: the immune system, having been chronically irritated by the asbestos fibers, seeks to isolate the fibers. When a sample of a plaque is observed under a microscope, one would expect to find collagen fibers—no cells or blood vessels—and asbestos fibers.
By nature, pleural plaques are benign, or non-cancerous. While they might lead to discomfort, like impaired breathing or chest pain, they don’t pose the same serious risks associated with a mesothelioma diagnosis. Like asbestosis, though, pleural plaques are caused by asbestos exposure. People’s bodies have different reactions to asbestos—largely depending on genetics and environmental factors—but the mechanisms that result in such different responses aren’t yet largely understood. Once scientists understand the difference between a “plaque response” and “mesothelioma response,” they might be able to alter people’s immune responses, especially if they’ve been exposed to asbestos.
Pleural plaques are diagnosed in similar ways to mesothelioma: X-ray, CT scan, and even biopsy.
After pleural plaques are diagnosed, there usually isn’t any treatment or intervention. Doctors might suggest some treatments, like physical therapy, for the sake of easing the discomfort associated with plaques. Besides pain-targeting treatments, though, plaques don’t get removed or treated otherwise.
Do Pleural Plaques Lead to Mesothelioma?
Although plaques themselves are benign, there isn’t a consensus about their possible contribution to a mesothelioma diagnosis. Some studies claim that the plaques might be an “independent risk factor” for developing mesothelioma, beyond asbestos exposure. So, this means that some researchers establish the chronic irritation inflicted by plaques as something that can cause mesothelioma. In one study (2013), researchers followed patients with plaques over a span of several years. 17 of the patients developed mesothelioma, which according to statistical analysis, was significant enough to establish an association.
Another study (2020) found that a regulatory gene, IL1B, factored into whether patients developed pleural plaques or mesothelioma, but didn’t establish a causatory “plaques cause mesothelioma.” Like mentioned above, patients’ genetic, epigenetic, and environmental milieus seem to contribute most to whether or not they’ll develop mesothelioma. Genetic differences in immune function and regulation seem to be a bigger “risk factor” than plaques, even though plaques might be an independent risk factor. Because of research ambiguity—and considering that patients with plaques have already been exposed to asbestos, which is causally related to mesothelioma—there isn’t clarity on the relationship between plaques and mesothelioma. It’s safe to assume that genetics play a greater role in mesothelioma development than plaques do. Because some patients exposed to asbestos only develop benign plaques, their genetic and immune mechanisms might shed light on the development (or non-development) of mesothelioma. In turn, these mechanisms could serve as a target for new therapies for mesothelioma.
If you or a loved one has been diagnosed with mesothelioma or another asbestos-related disease, please call 1 (800)-505-6000 or fill out our form. We are here to help you navigate the legal process of filing a claim to receive compensation for your mesothelioma diagnosis. We help mesothelioma victims and their families in Pennsylvania.
Frequently Asked Questions
What are pleural plaques?
Pleural plaques are benign, non-cancerous growths made of collagen that develop in the pleura — the tissue lining surrounding the lungs, abdomen, or heart. They form as the body’s immune system attempts to isolate asbestos fibers that have become embedded in tissue. Under a microscope, pleural plaques contain collagen fibers and asbestos fibers but no cells or blood vessels. They are the most common physical response to asbestos exposure.
Are pleural plaques dangerous?
Pleural plaques themselves are benign and not directly dangerous. They are not cancerous and do not carry the same prognosis as mesothelioma. However, they can cause discomfort — including chest pain and impaired breathing — depending on their size and location. More importantly, the presence of pleural plaques confirms that asbestos exposure has occurred, which means the patient is at elevated risk for other asbestos-related diseases, including mesothelioma, lung cancer, and asbestosis.
Can pleural plaques turn into mesothelioma?
This is an active area of research without a definitive answer. Some researchers suggest that the chronic irritation caused by plaques could be an “independent risk factor” for developing mesothelioma — a 2013 study found that 17 patients with plaques later developed mesothelioma, suggesting a statistically significant association. However, a 2020 study found that genetic differences — specifically in a regulatory gene called IL1B — may determine whether a patient develops plaques or mesothelioma, without establishing a causal link between the two. The current consensus is that genetics and immune function play a larger role than the plaques themselves.
How are pleural plaques diagnosed?
Pleural plaques are diagnosed using the same imaging tools used for mesothelioma:
- Chest X-ray — can reveal the presence of calcified plaques
- CT scan — provides more detailed images showing the size, location, and extent of plaques
- Biopsy — in some cases, a tissue sample may be taken to confirm that the growths are benign plaques and not cancerous
Pleural plaques are often discovered incidentally during imaging performed for other reasons — many patients are unaware they have them until they show up on a scan.
Is there treatment for pleural plaques?
There is no standard treatment for pleural plaques — they are not removed or treated directly. When symptoms like chest pain or breathing difficulty occur, doctors may recommend symptom management approaches such as physical therapy, pain medication, or breathing exercises. Because plaques are benign, the focus is on monitoring the patient for any signs of progression to more serious asbestos-related conditions.
Why do some people get plaques while others get mesothelioma?
This is one of the most important unanswered questions in mesothelioma research. Both conditions are caused by asbestos exposure, but the body’s response differs dramatically from person to person. Research suggests that genetic factors, epigenetic differences, and variations in immune function are the primary determinants. The 2020 IL1B study found that specific gene variants influence whether the body responds to asbestos with benign plaque formation or cancerous growth. Understanding these protective mechanisms in plaque-only patients could eventually lead to new therapeutic targets for mesothelioma.
What should I do if I’ve been diagnosed with pleural plaques?
A pleural plaque diagnosis confirms that asbestos exposure has occurred, which means you should be monitored for other asbestos-related conditions. Inform your doctor about your full exposure history and ask about ongoing screening — including imaging and biomarker blood tests — to detect any changes early. If you or a loved one has been diagnosed with pleural plaques, mesothelioma, or another asbestos-related disease, call (800) 505-6000 or fill out our contact form for a free consultation.
