Mesothelial cells are the cells that cover our internal organs such as our lungs, liver, stomach, and colon. They form a barrier on the outside of these organs that protect the organs from injury.
These cells respond to injury or damage by becoming larger. Pathologists call these cells reactive mesothelial cells. Nearby cancer cells also cause these cells to become reactive.
Mesothelioma is a type of cancer that starts from mesothelial cells. This type of cancer is most common around the lungs, but it can also start in the abdomen or pelvis. Another name for mesothelioma is malignant mesothelioma.