Retiform hemangioendothelioma: An uncommon vascular neoplasm

Retiform hemangioendothelioma is a rare vascular neoplasm of intermediate grade, the diagnosis of which can be challenging. We report a case of 35-year-old man with swelling in the postauricular region. He had undergone FNAC which had revealed blood only. Microscopic examination showed narrow, arborizing, vascular channels resembling normal rete testis. Evidence of mitoses or cytological atypia were lacking. Immunohistochemistry showed diffuse and strong staining for CD34 along with CD31 positivity. Immunostains for D240 and GLUT1 were negative. A diagnosis of retiform hemangioendothelioma was made. Histologically, it should be distinguished from Kaposiform hemangioendothelioma, Dabska tumor, epithelioid hemangioendothelioma, and angiosarcoma.