Overview

What is cancer?

Cancer is the uncontrolled growth of cells in an organ, such as the lung, colon or skin. Cancer cells grow together to form a mass called a tumor. Benign (non-cancerous) cells can also grow and spread, but are not invasive. Cancer can be life threatening, because malignant cells can invade surrounding tissue and spread, or metastasize, to other parts of the body. Early detection before the cancer spreads provides the best chance of cure.

Definition

Mesothelioma is a form of cancer that arises from mesothelial cells that form membranes around the lungs, abdomen and other body cavities. Mesothelial cells produce a minute amount of lubricating fluid that helps the lungs expand and allows abdominal organs to move easily against one another.

Mesothelioma occurs when these cells grow and spread uncontrollably. Beginning first as a flat white plaque, mesothelioma is a tumor that continues to grow around the lungs (pleurae), but may also originate around the abdominal cavity. As mesothelioma progresses, it enters the lungs and invades nearby ribs.

About 2,000 new cases of mesothelioma are diagnosed in the United States each year. Most people with mesothelioma have worked in jobs where they breathed in fibers of asbestos. Others have been exposed to asbestosis fibers in their homes, often without knowing it.

Like most cancers, the outlook for recovery often depends on how early the disease is diagnosed and how aggressively it is treated. Mesothelioma is usually fatal, with a life expectancy of up to 18 months after diagnosis. However, there are experimental treatments that may extend life.

More on Mesothelioma

This article was reviewed and updated June 2007.