The risks associated with this syndrome include a substantial risk of cancer, especially of the breast and gastrointestinal tracts. Colorectal is the most common malignancy, with a lifetime risk of 39 percent, followed by breast cancer in females with a lifetime risk of 32 to 54 percent. Patients with the syndrome also have an increased risk of developing carcinomas of the liver, lungs, breast, ovaries, uterus, testes, and other organs. Specifically, it is associated with an increased risk of sex-cord stromal tumor with annular tubules in the ovaries. Due to the increased risk of malignancies, direct surveillance is recommended. The average age of first diagnosis is 23. The first presentation is often bowel obstruction or intussuseption from the hamartomatous gastrointestinal polyps. Dark blue, brown, and black pigmented mucocutaneous macules, are present in over 95 percent of individuals with<unk> . Pigmented lesions are rarely present at birth, but often appear before 5 years of age. The macules may fade during puberty. The mealoncytic macules are not associated with malignant transformation. Complications associated with<unk>  include obstruction and intussusception, which occur in up to 69 percent of patients, typically first between the ages of 6 and 18, though surveillance for them is controversial. Anemia is also common due to gastrointestinal bleeding from the polyps.
Peutz–Jeghers syndrome
Juvenile polyp
Familial adenomatous polyposis
Nijmegen breakage syndrome
MUTYH-associated polyposis
Juvenile polyposis syndrome
Serrated polyposis syndrome
Li–Fraumeni syndrome