Histology Fact Sheet:
Understanding the Normal Histology behind Mesothelioma

In order to more fully understand the pathology of mesothelioma, one must first understand normal anatomy and histology.

Mesothelioma is a type of cancer derived from the mesothelium. Mesothelium is a type of epithelium. Specifically, mesothelium is a simple squamous epithelium that covers serous membranes.

Mesothelium is found in membranes lining the thoracic, abdominal and pericardial cavities.

Many body parts can be affected by mesothelioma. Mesothelioma may originate in the pleura, peritoneum, pericardium and genital tract. The pleura is the membrane in the thoracic cavity. The peritoneum is membrane which lines the abdominopelvic cavity. The pericardium is the membrane around the heart.

The most common site for mesothelioma to originate is the pluera. The pleura can be divided into visceral and parietal pleura.

The visceral pleura is a membrane which covers the surface of the lung. The visceral pleura is composed of mesothelium overlying connective tissue.

In between the visceral pleura and parietal pleura is a small amount of fluid.

The parietal pleura is the outer covering.

Mesothelioma X-ray
Mesothelioma image courtesy of CDC