Peutz-Jeghers syndrome is inherited as an autosomal dominant trait with variable incomplete penetrance. Patients with Peutz-Jeghers syndrome characteristically have hamartomatous polyps throughout their entire gastrointestinal tract, particularly in the small bowel, and mucocutaneous hyperpigmentation involving the lips, oral cavity, and skin. Although the intestinal hamartomatous polyps have a lower incidence of malignant change in the gastrointestinal tract than do adenomatous polyps, recent information suggests that the overall neoplastic transformation from Peutz-Jeghers syndrome is not a rare event.