Intestinal lipoma. Endoscopic view of the interior of a patient's ileum (small intestine), showing a lipoma (right) on the ileocaecal valve. A lipoma is a benign (non-cancerous) tumor composed of adipose tissue (body fat). The ileocaecal valve is a sphincter muscle situated at the junction of the ileum and the caecum, the beginning of the large intestine. Its critical function is to limit the reflux of colonic contents into the ileum.