A 5-year-old girl is brought to the physician after her parents noticed red blood in her stool. Physical examination reveals mucocutaneous pigmentation. Small bowel radiography discloses multiple, small- to medium-sized polyps that are diagnosed pathologically as hamartomas. Which of the following is the most likely diagnosis?

Peutz-Jeghers syndrome is an autosomal dominant, hereditary disorder characterized by intestinal hamartomatous polyps and mucocutaneous melanin pigmentation, which is particularly evident on the face, buccal mucosa, hands, feet, and perianal and genital regions. The polyps seen in Peutz-Jeghers syndrome are hamartomatous, characterized by a branching network of smooth muscle fibers continuous with the muscularis mucosa that support the glandular epithelium of the polyp. Congenital teratoma (choice A) does not involve the intestine. The other choices are principally colonic polyps that derive from the luminal epithelium.Diagnosis: Gastrointestinal polyp, Peutz-Jeghers polyp