Pleural Plaques

The pleura are two thin layers of tissue that surround the lungs and line the chest cavity. When cancer begins in this tissue it is called pleural mesothelioma, but there are other problems that can originate here that may or may not be related to cancer. Pleural plaques are areas of thickened tissue in the pleura, most often caused by asbestos. Pleural plaques are the most common signs of damage to the chest cavity related to asbestos exposure.

Plaques may not develop until many decades after exposure to asbestos. They do not typically cause symptoms and they may or may not develop into malignant pleural mesothelioma. By themselves, plaques are benign and do not cause health problems. They will not necessarily progress or get worse over time. Treatment is not really necessary for plaques, but monitoring them for progression or cancer is important.

A Common Result of Asbestos Exposure

Asbestos, the natural material that has been used so extensively in construction, ship building, and other industries, has caused untold damage to people who had to work around it. If you worked around asbestos for your career you may have breathed in the loose fibers of this material. Those fibers, once inhaled, easily get lodged in tissues in the body. Most often they end up in the pleura of the chest cavity.

Once lodged in place these fibers may cause damage. Not everyone who was exposed to asbestos will experience tissue damage, but among those who do, pleural plaques are very common. A plaque occurs when the asbestos fibers cause a small area of tissue to become fibrous and hard. Exactly why this happens is not fully understood, but is likely related to the fibers of asbestos triggering inflammation and the formation of scar tissue.

Pleural plaques are the most common complications of asbestos exposure because their formation can be triggered by lower levels of exposure as compared to conditions like asbestosis and mesothelioma. Research also suggests that plaque development is slow and that they may not show up on imaging scans until many years after an initial exposure to asbestos.

How Pleural Plaques Form

Researchers do not understand exactly how these plaques form. They may be caused by inflammation and scar tissue, but there may be other pathways that lead to plaques. For instance, on idea is that the asbestos fibers trigger an immune system response. This may cause a type of immune cell called a macrophage to come to the site of damage and cause a reaction that leads to fibrosis and hardening of the tissue. The scar tissue that forms is made of collagen.

Pleural Plaques vs. Pleural Thickening

Pleural thickening is also a fairly common result of asbestos damage to the pleura, and these two are easy to confuse. Plaques are most often benign; they are small and spaced apart; and they do not often cause symptoms. Thickening on the other hand is more widespread; it likely will affect the entire pleural surface and get worse over time. Pleural thickening also causes symptoms, which worsen as the condition progresses.

Symptoms of Pleural Plaques

For most people with pleural plaques there are no symptoms or the symptoms are very mild. Some research has found that people with plaques have a slightly diminished lung capacity and that they may have slightly impaired lung function. Rarely a person with pleural plaques may experience chest pains and difficulty breathing.

Diagnosing Pleural Plaques and Mesothelioma

Most people who are diagnosed as having pleural plaques had no symptoms leading up to the diagnosis. Often the diagnosis is made after a patient has a chest X-ray done for other reasons. The plaques may show up on the X-ray image, even though they are causing symptoms. If plaques are discovered on your X-ray, talk to your doctor about the possibility of being at risk for mesothelioma and further tests to find out if you have early signs of the cancer.

Imaging scans, like CT scans, may show a pleural plaque as a mass on the lungs or pleura. This can be confused with cancer, so an imaging test is not necessarily considered a definite diagnosis. A biopsy should be done when it is unclear whether an abnormality or mass is a plaque or a cancerous growth. This means taking a small sample of the abnormal tissue, usually through the insertion of a long, thin needle, and then investigating the sample under a microscope. A pathologist can look at the cells in the sample and determine if they are malignant or benign.

Treatment

For most people diagnosed with pleural plaques, there is no treatment necessary. The plaques are not likely to cause symptoms or to progress, become worse, or cause more damage. However, if you do discover that you have plaques, it is important to take steps to reduce risk factors for related diseases, like mesothelioma. If you are still around asbestos, through work or other sources, take steps to eliminate that exposure. Stop smoking if you smoke and ask your doctor for advice on what else you can do to minimize your risks. If you do have some symptoms, your doctor can prescribe medications or therapies that may help.

Outlook

The outlook for being diagnosed with pleural plaques is generally good. There is no evidence that these plaques are likely to develop into mesothelioma or lung cancer. However, plaques are a risk factor for these types of cancer because they indicate that you were likely exposed to asbestos at some point. Any exposure to asbestos puts you at risk for later developing mesothelioma. Keep an eye on your symptoms, try to reduce risk factors, and see your doctor for regular screenings.

Pleural plaques are not usually serious health problems, and they are not likely to cause any debilitating symptoms. These could, however, be a wakeup call to help you realize that asbestos may have been in your workplace and that you may have been exposed and put at risk for mesothelioma. If you get sick with other related conditions, find out how a mesothelioma lawyer or asbestos trust fund could help you get compensation.