Small bowel tumors: pathology and management.

Despite comprising at least 75% of the length of the gastrointestinal tract, the small bowel only accounts for 3 to 6% of all its neoplasms. Forty different tumor subtypes arise from the small bowel; the commonest is adenoma, and malignant lesions include gastrointestinal stromal tumor neuroendocrine tumor lymphoma, and adenocarcinoma. Small bowel tumors typically cause either non-specific symptoms or none at all, which explains both the frequent delay in diagnosis and the wide range of potential investigations. The relative inaccessibility of the small bowel to endoscopic assessment is being challenged by the increased use of both capsule and double balloon endoscopy. Advances in endoscopic assessment are mirrored by improved sensitivity of radiological and nuclear imaging. Operative resection provides the mainstay of treatment for malignant disease (and symptomatic benign lesions), with oncological agents and somatostatin analogues providing useful adjuncts for inhibiting tumor growth and relieving symptoms. Survival reflects underlying tumor subtype, but is generally poor for malignant disease.