cancer of the small intestine

cancer of the small intestine,

a neoplastic disease of the duodenum, jejunum, or ileum. Its characteristics vary, depending on the kind of tumor and the site, but may include abdominal pain, vomiting, weight loss, diarrhea, intermittent bowel obstruction, GI bleeding, or a mass in the right abdomen. Diagnosis typically is made with barium radiographic examination, but results of such studies may be inconclusive until lesions are large. Adenocarcinomas, the most common tumors, occur more frequently in the duodenum or upper jejunum and form polypoid or constricting napkin-ring growths. Lymphomas, found most often in the lower small intestine, may impair bowel motility by invading nerves and in some cases are associated with a malabsorption syndrome. Less common tumors of the small intestine are carcinoids, usually found in the ileum, and sarcomas, including Kaposi's sarcoma, usually seen in the jejunum and ileum. A leiomyosarcoma may sometimes form a large extraluminal mass. Surgery, including a wide resection of mesenteric lymph nodes, is typically indicated for adenocarcinomas and carcinoids. Irradiation occasionally is indicated. Chemotherapy is often useful, particularly for lymphoma.