Hamartomatous Tumors in the Gastrointestinal Tract.

BACKGROUND Digestive hamartomatous polyps are a rare entity. They may be sporadic (solitary Peutz-Jeghers polyp or solitary juvenile polyp) or reveal genetic predisposition like Peutz-Jeghers syndrome, juvenile polyposis or Cowden disease. SUMMARY Diagnosis is based on personal and family history and on clinical data including physical signs (in particular dermatological), endoscopic findings (the number of polyps) and histological features of the polyps. The risk of complications and of digestive and extra-digestive cancers may be high, especially in case of genetic predisposition syndromes, and requires multidisciplinary management of the patients (oncogenetic counseling, gastroenterologist, pathologist, dermatologist, gynecologist and endocrinologist). Endoscopic evaluation is very helpful to establish the current situation, to perform polypectomy and to allow for good histological examination of the polyps, whose degeneration has been exceptionally described. The recent development of new molecular techniques (next-generation DNA sequencing) allows for rapid multiple gene sequencing and facilitates diagnosis. KEY MESSAGE Discovery of a hamartomatous polyp requires a rigorous work-up which should be performed by a multidisciplinary team, including a genetic oncologist, experienced in this pathology. PRACTICAL IMPLICATIONS The diagnostic procedure in hamartomatous polyps should be based on the number of polyps identified during endoscopy (solitary versus multiple) and on their histological characteristics. The clinical examination must search for mucosal and skin lesions. If a polyposis syndrome is identified, oncogenetic consultation is necessary in order to define screening modalities for family members, aiming at preventing cancer development. Endoscopic resection (polypectomy) of the lesions may prevent complications like bleeding and degeneration and also diminish the risk of surgery and subsequent short bowel syndrome.