Diffuse cavernous hemangioma of the colon in the Klippel-Trenaunay syndrome.

Large, infiltrative cavernous hemangiomas of the distal colon were present in 3 children with the Klippel-Trenaunay syndrome, 2 of whom are the subject of this report. The lesion is manifested clinically as intermittent rectal bleeding starting in the first 5 years of life. The radiographic features include (a) varicose lesions in the wall of the rectosigmoid, ranging from a network of distended submucosal veins to nodular defects, (b) narrowing of the rectum by the surrounding extramural portion of the hemangioma, and (c) phleboliths within the lesion. Inferior mesenteric angiography and sigmoidoscopy are useful for preoperative confirmation. The occurrence of visceral hemangiomas in the Klippel-Trenaunay syndrome and its relevant diagnostic and therapeutic implications are discussed.