ANALYSIS OF VASCULARITY OF HUMAN NEUROFIBROMAS

Background: A common misperception is that the vascularity of a tumor can be determined by its gross appearance. Neurofibromas are grossly w hite in appearance. The degree of vascularity of neurofibromas has not been determined. Objective: The purpose of this study was to determin e the extent of neovascularization of neurofibromas. Methods: Neurofib romas from patients with neurofibromatosis-1 or spontaneous neurofibro mas were stained with antibodies against von Willebrand factor (factor VIII-related antigen) and vascular endothelial growth factor (VEGF). Results: Neurofibromas, both spontaneous and congenital, exhibit a hig h degree of vascularity. In addition, perivascular cells in neurofibro mas stain with antibodies to VEGF, an angiogenic factor. Conclusion: N eurofibromas, despite their gross appearance, are highly vascular. The ir vascularity may be mediated, in part, through the angiogenic factor VEGF.