Definition

A rare, inherited disorder in which multiple abnormal growths called juvenile polyps form in the gastrointestinal tract, usually before the age of 20 years. To be diagnosed with juvenile polyposis syndrome, a person must have one or more of the following: (1) more than five juvenile polyps in the colon or rectum; (2) juvenile polyps in other parts of the gastrointestinal tract, including the stomach or small intestine; (3) any number of juvenile polyps and a family history of juvenile polyposis syndrome. Other signs and symptoms include diarrhea, gastrointestinal bleeding, abdominal pain, anemia, extra fingers and toes, and abnormalities of the heart, brain, roof of the mouth, intestines, urinary tract, and genitals. People with juvenile polyposis syndrome also have an increased risk of colorectal cancer, stomach cancer, small intestine cancer, and pancreatic cancer. Juvenile polyposis syndrome is caused by mutations (changes) in the SMAD4 or BMPR1A genes that are inherited in an autosomal dominant manner. It is a type of hereditary cancer syndrome. Also called JPS.