Lack of expression of podoplanin by microvenular hemangioma.

Microvenular hemangioma (MH) is not a very common type of hemangioma, and it can occasionally be difficult to distinguish it from other benign vascular tumors and malignant tumors such as Kaposi's sarcoma. The latter has been shown to be negative for the marker D2-40. Nevertheless, the status of MH for D2-40 has not been established yet. We therefore studied the expression of podoplanin in three cases of MH using D2-40 antibody. No expression was seen, while the dermal lymphatics were clearly immunostained. Nevertheless, the vessels of the MHs were positive for CD34, CD31, and von Willebrand Factor. This study adds MH to the list of vascular lesions that fail to express the allegedly lymphatic marker podoplanin.