Polyps and Tumors of the Gastrointestinal Tract in Childhood

Although a wide variety of polyps and tumors occur in the pediatric gastrointestinal tract, the incidence and pathologic types encountered differ from adults. Some of them may have unique associations with developmental and syndromic disorders, the recognition of which may be critical in clinical management. This chapter begins with a summary of the epidemiology of pediatric gastrointestinal polyps and masses, and continues with more detailed sections focusing on the etiology, clinical features, pathologic findings and molecular genetics of specific gastrointestinal polyposis syndromes and gastrointestinal tumors. Major entities covered in the section on polyps include juvenile polyposis, Peutz–Jeghers syndrome, PTEN hamartoma tumor syndrome, familial adenomatous polyposis and inflammatory polyps. The section on tumors summarizes the literature on the various tumors that have presented in the pediatric gastrointestinal tract, with emphasis on colorectal carcinoma, neuroendocrine tumors, lymphoproliferative disorders, gastrointestinal stromal tumors and inflammatory myofibroblastic tumors.