Generalized juvenile polyposis can be inherited or sporadic. The polyps may be found anywhere in the intestinal tract and are characterized by their microscopic appearance. Large polyps may present with symptoms of obstruction or bleeding and there is a small increased risk of developing gastrointestinal cancer. The polyps are most commonly found in the small intestine and usually do not become malignant. Adenocarcinoma Adenocarcinoma of the small bowel probably develops mainly from adenomas.
Most tumors occur at the ampulla in the duodenum.
Patients can present with obstruction or bleeding. Treatment depends on the location, size and shape of the tumor, and whether it has spread. Intestinal lymphoma of the small bowel is a recognized complication of celiac sprue, and can occur in immunodeficiency syndromes. These lymphocytic tumors are also more common in men, occur in middle age or later years. Symptoms include crampy-like abdominal pain, weight loss, features of malabsorption , bleeding, or even bowel obstruction.