The mesothelioma pleural membrane that covers the chest wall and that also wraps around the lungs providing a protective covering. All of these linings or membranes that wrap organs and internal cavities are considered a single anatomical feature called the mesothelium. It is viewed as one large membrane and it is the location where asbestos fibers create malignancy, whether it is in the abdomen (peritoneal mesothelioma); in the membrane around the heart (pericardial mesothelioma); or in the lining on the outside of the lungs (pleural mesothelioma).

The lining on the chest wall is called the parietal pleura; the membrane wrapped around the lungs is known as the visceral pleura. These two membranes in the chest cavity are where seventy percent or more of all mesothelioma pleural cases develop. The term “effusion” is used for medical purposes to denote the abnormal buildup of fluid. Pleura effusion, then, is the development of excess fluid in the pleural space or pleural cavity – the area between the two pleural membranes.

Asbestos and Pleural Effusion

There is also a further division of the pleural mesothelium – that portion wrapped around the lungs is called the visceral pleura, while the lining of the chest wall is known as the parietal pleura. These two surfaces have a thin layer of liquid between them that provides lubrication during the breathing process; because the pleural surfaces are separated by fluid they do not rub together with every breath.

mesothelioma pleural

Asbestos fibers most often make their way into the human body through inadvertent inhalation. They are invisible to the eye and go unnoticed when inhaled in a cloud of industrial dust. Often they make their way through the lung wall and into the outer lining, or visceral pleura. As time passes, the fibers become an irritant and eventually cause the growth of deformed malignant cells that begin reproducing at an uncontrollable rate, causing inflammation of the pleura. This symptom often triggers the production of excess fluid in the area, resulting in pleural effusion. The malformed cells cause the pleural surfaces to thicken and an excess of fluid develops between them; these are the elements of pleural effusion.

This mesothelioma symptom is always asymmetrical; it develops on one side of the body or the other, impacting one lung or the other. Localized effusion is present in over 50% of all mesothelioma patients, and in a higher percentage of mesothelioma pleural victims.