Diseases of Pigment

Peutz-Jeghers syndrome is a rare genetic disorder that causes small spots on the mouth, fingers, and lips. The condition also causes the formation of polyps in the intestines. The syndrome substantially increases the risk of cancers of the stomach, rectum, esophagus, breast, ovaries, pancreas, testes, and colon. The middle part of the small intestine, the jejunum, is most often affected by polyps. The inheritance of Peutz-Jeghers syndrome is in an autosomal dominant pattern. A mutation in a tumor suppressor gene called STK11 causes the condition.