Vascular tumors and malformations of the colon

Abstract

The term “hemangioma” refers to the common tumor of infancy that exhibits rapid postnatal growth and slow regression during childhood. It may cause confusion with venous malformations that are often incorrectly called “cavernous hemangioma”. Venous malformations comprise abnormally formed channels that are lined by quiescent endothelium. Accurate diagnosis is required for selecting the appropriate treatment.

Key Words: Hemangioma; Venous malformations; Surgery; Sclerotherapy; Colon

TO THE EDITOR

With regard to the article entitled “Large cavernous hemangioma in the cecum treated by laparoscopic ileocecal resection” by Huh et al[1] published recently on the World Journal of Gastroenterology, there are some pertinent considerations. In 1982, Mulliken and Glowacki[2] classified vascular lesions into vascular tumors (infantile hemangioma, rapidly involuting congenital hemangioma, non-involuting congenital hemangioma, kaposiform hemangioendothelioma and tufted angioma) and vascular malformations (arteriovenous malformation, venous malformation, lymphatic malformation, lymphatic-venous malformation, and capillary malformation). In 1996, the International Society for the Study of Vascular Anomalies approved this classification system to establish a common language for the many different medical specialists who are involved in the management of these lesions. A great variety of vascular anomalies is incorrectly referred to as “hemangiomas” in the medical literature and a significant number of patients receive ineffective and potentially harmful treatment based on misclassification. Hemangiomas are usually not present at birth; they proliferate during the first year of life; and then they involute. They are composed of proliferating endothelial cells. Venous malformations consist of dysplastic vessels and are present on a lifelong basis. Unlike hemangiomas, there is no proliferation phase. They seem to grow because the vessels progressively dilate and they do not present a regression phase[3]. Histological findings in venous malformations consist of large, dilated, blood-filled vessels lined by flattened endothelium as reported in the article.

After close examination of the reported case of “cavernous hemangioma”, we support the diagnosis of venous malformation in the cecum. Colonic venous malformations are often mistaken for tumors because of a similar presentation (from a vague blue patch to a soft blue mass as described in the article) and improper nomenclature. The term “cavernous hemangioma” is frequently used to name a venous malformation. These lesions may cause chronic and acute gastrointestinal hemorrhage.

Sclerotherapy of venous malformations is an effective treatment and seems to be the best therapeutic option, although the surgical resection is preferred for venous malformations localized in the colon in case of bleeding. Although these vascular malformations generally are incompletely resectable because of diffuse pelvic and mesenteric involvement, the goal is to abate bleeding by excluding the lesion from the gastrointestinal lumen. The minimally invasive surgical procedure performed by the authors of this article seems to be appropriate since the venous malformation was removed from the lumen. Other procedures like colectomy with mucosectomy and endorectal pull-through should be considered for diffuse venous malformations of the colorectum[4].