1. ¹Department of Pathology, Children's Hospital, Harvard Medical School, Boston, MA, USA
2. ²Department of Surgery, Children's Hospital, Harvard Medical School, Boston, MA, USA
3. ³Department of Medicine, Children's Hospital, Harvard Medical School, Boston, MA, USA

Correspondence: Dr LV Debelenko, MD, PhD, Department of Pathology, Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA. E-mail: Larisa.Debelenko@childrens.harvard.edu

Received 19 October 2004; Revised 15 April 2005; Accepted 15 April 2005; Published online 20 May 2005.

Abstract

Kaposiform hemangioendothelioma is a distinctive vascular neoplasm affecting predominantly children and neonates. In neonates it needs to be differentiated from common infantile hemangioma and other vascular lesions of infancy. Kaposiform hemangioendothelioma immunoreacts with vascular endothelial growth factor receptor 3, and partial lymphothelial differentiation of this lesion has been suggested. D2-40 has been recently proposed as a selective marker of lymphatic endothelium. We performed immunohistochemical analysis with the D2-40 antibody on 24 kaposiform hemangioendotheliomas and 48 other pediatric vascular lesions including common infantile hemangioma (n=10), rapidly involuting congenital hemangioma (n=10), noninvoluting congenital hemangioma (n=9), verrucous hemangioma (n=9), and pyogenic granuloma (n=10) to define whether this marker can be applied in the diagnosis of vascular lesions of infancy. In all, 23 of 24 (96%) kaposiform hemangioendotheliomas exhibited a distinct staining, while none of the other lesions immunoreacted with D2-40. D2-40 stained the neoplastic spindled cells and lymphatic channels adjacent to vascular lobules of kaposiform hemangioendothelioma. These findings support D2-40 as a new determinate marker for kaposiform hemangioendothelioma, useful in differentiating it from other vascular lesions of infancy and suggest lymphothelial differentiation of the neoplastic component of kaposiform hemangioendothelioma. Further studies are necessary to define the identity of the D2-40 antigen and to elucidate the biologic significance of its selective lymphothelial reactivity.