What Are Pleural Plaques?

Pleural plaques are areas of thickened tissue that form in the lining of the lungs, known as the pleura. These plaques are a noncancerous asbestos-related condition. Another term for pleural plaques is hyaline pleural plaques, as they contain hyaline tissues found in cartilage.

Illustration of Pleural Plaques in the Parietal Layer of the Pleura
Pleural plaques develop on the outermost layer of the lining around the lungs called the pleura.
Illustration of Pleural Plaques in the Parietal Layer of the Pleura

After asbestos exposure, pleural plaques can form on both layers of the pleura. Oncologists note that while pleural plaques themselves don’t lead to cancer, they may increase the risk for pleural mesothelioma or asbestos-related lung cancer.

Most people with pleural plaques don’t exhibit obvious symptoms. However, some patients report experiencing pain or an uncomfortable grating sensation as they breathe.

Key Facts About Pleural Plaques
  • Pleural plaques are usually asymptomatic.
  • Calcified pleural plaques form on the pleural surface.
  • In a 2023 study of 102 asbestosis patients, pleural plaques were present in 94% of patients.

What Causes Pleural Plaques?

Prolonged asbestos exposure is the primary cause of pleural plaques. Inhalation of asbestos fibers can cause buildup in the lung lining, irritating lung tissue. Studies show fibers reach the pleural space through the lymphatic system.

Research suggests asbestos fibers cause an immune response of cells called pleural macrophages. These cells trigger inflammation, leading to fibrosis when connective tissue replaces normal, healthy lung tissue with collagen fibers. These fibrous areas are also called scar tissue.

The thick pleural tissue does not always lead to mesothelioma. However, a 2022 ScienceDirect case study identified several outstanding diagnostic factors of mesothelioma. These included bilateral pleural plaques, nodules and pleural effusions.

Dr. Jacques Fontaine and Dr. Andrea Wolf
Find a Top Mesothelioma Doctor

Gain access to top mesothelioma doctors and get help scheduling appointments.

Connect Now

What Are the Symptoms of Pleural Plaques?

Pleural plaques do not usually cause any symptoms. However, a small percentage of patients have reported mild symptoms such as a grating sensation when they breathe and chest pain. Recent evidence shows they sometimes cause a slight decrease in total lung capacity. Plaques may also affect other measures of lung function, such as expansion.

People with pleural plaques may experience many symptoms that stem from underlying causes, such as asbestosis, mesothelioma and pleural thickening. Notify your doctor if you experience any symptoms. Your doctor may refer you to a specialist for more severe breathing issues.

Asbestos-exposed patients with pleural plaques may develop pleural thickening. This  thickening of the lung lining affects a larger area than plaques and can prevent the lungs from expanding. It can also cause difficulty breathing, a persistent or bloody cough, or chest pain. These may be signs of a more severe and undiagnosed condition.

How Are Pleural Plaques Diagnosed?

Doctors diagnose pleural plaques using imaging scans such as X-rays or CTs. For many people, pleural plaques appear incidentally during routine tests. Doctors often identify the plaques by chance during chest imaging for other illnesses. Discuss your imaging scans with a mesothelioma specialist to get a second opinion.

X-ray of calcified asbestos pleural plaques
Close-up X-ray of calcified asbestos pleural plaques.

“For patients looking for a second opinion, it’s really about the imaging,” said Dr. Jeffrey Velotta, a thoracic surgeon at Kaiser Permanente. “It’s so easy now to send it electronically or over email. When you ask for your medical records, there can be a lag time if you ask for your whole chart. We need to see the CT scan first.”

Diagnosis With CT Scan

A CT scan is the most accurate test for diagnosing pleural plaques. It is 95% to 100% correct in identifying this condition. The test can reveal plaques anywhere in the chest, even if they are not calcified.

After diagnosing pleural plaques, your doctor will review other signs of asbestos-related disease. They will customize a unique treatment plan if you have an asbestos-related illness.

Discovery Through X-Ray

Radiologists find most pleural plaques after an X-ray. This test reveals areas with thickened nodular edges resembling a holly leaf. 

Calcified pleural plaques appear as translucent white deposits on the lungs. In specific locations, these plaques can be difficult to identify via X-ray.

Survivor Story
Survivor Story
Jack Riordan Pleural mesothelioma

Mesothelioma Survivor Was First Diagnosed With Pleural Plaques 30 Years Ago

Jack Riordan was diagnosed 30 years ago with pleural plaques, an asbestos-related condition. When shortness of breath became an issue, he knew it might be severe. He had spent much of his career working with asbestos insulation, doing asbestos abatement and general contracting. He said of his mesothelioma diagnosis, “I knew this was a possibility a long time before.”

Read Jack’s Story

How Are Pleural Plaques Treated?

Doctors do not treat pleural plaques as a standalone illness. They are noncancerous, and most patients do not experience a loss in lung function. 

Although there is no treatment for pleural plaques, you can take steps to prevent further damage. If you are a smoker, ask your doctor for help with a smoking cessation program.

If you must work around asbestos, you can avoid further exposure by using personal protective equipment such as a respirator with a HEPA-certified filter and disposable coveralls. You can also minimize exposure to air pollution by heeding warnings to stay indoors when pollution levels are highest, such as during wildfires.

Find a Specialist Near You

Don’t see your state? Find out how our Doctor Match program can help.

Are Pleural Plaques Related to Cancer?

Pleural plaques are not a form of cancer, although pleural plaques and fibrous thickening may increase your risk of pleural mesothelioma and lung cancer.

Plaques can harden over time but do not cause long-term health problems for most people. However, in addition to cancer, frequent or extended asbestos exposure can cause more severe noncancerous illnesses, such as asbestosis.

Tell your provider about past asbestos exposure. The details could prompt your doctor to test for other asbestos-related diseases.

Recommended Reading
  •  
  •  
  •  
Tell us what you think
Did this article help you?
How did this article help you?
What about this article isn’t helpful for you?
Did this article help you?

Thank you for your feedback. Would you like to speak with a Patient Advocate?

Connect with Our Community

Get in Touch

Have questions? Call or chat with our Patient Advocates for answers.

Join Our Support Group

Join our support groups to connect and learn from others with mesothelioma.

Upcoming Events

Upcoming Events: Check the calendar for dates and details.