Peutz–Jeghers Syndrome: A Rare Case Report with Emphasis on Oral Manifestations

Peutz–Jeghers syndrome (PJS) is a rare autosomal dominant disorder characterized by mucocutaneous pigmentation and multiple gastrointestinal hamartomatous polyps, associated with an increased lifetime risk of malignancy. Early recognition is essential to prevent potentially serious gastrointestinal complications, including intestinal obstruction and intussusception. This case report describes a 50-year-old female who presented to the Department of Oral Medicine with multiple asymptomatic, well-defined, dark-brown to bluish-pigmented macules involving the lower lip, buccal mucosa, and palate. The patient had a previous history of gastrointestinal symptoms and intestinal polyps. Gastrointestinal endoscopic examination revealed multiple polyps, while histopathological assessment demonstrated characteristic hamartomatous polyps with arborizing bundles of smooth muscle. A family history of gastrointestinal polyposis was also reported, supporting the hereditary nature of the condition. The clinical findings were consistent with Peutz–Jeghers syndrome, which is associated with pathogenic variants in the STK11 tumor suppressor gene. This case highlights the importance of recognizing characteristic oral and perioral pigmentation as a potential indicator of an underlying systemic disorder. Dental and oral medicine practitioners play an important role in the early identification and referral of suspected cases for appropriate gastrointestinal evaluation, genetic counseling, and lifelong surveillance to reduce the risk of associated complications and malignancies.