Definition

A rare genetic disorder in which many polyps (abnormal growths of tissue) form in the lining of the gastrointestinal tract, and dark-colored spots appear on certain areas of the skin, such as around the mouth, eyes, and nose. People with Peutz-Jeghers syndrome have a very high risk of developing gastrointestinal cancer and other types of cancer, including cancers of the breast, pancreas, ovary, lung, and cervix. Peutz-Jeghers syndrome is usually caused by mutations (changes) in the STK11 gene. Some people with Peutz-Jeghers syndrome do not have a mutation in the STK11 gene. In these cases, the cause of the disorder is unknown. Also called PJS.