The authors evaluated the histologic, immunohistochemical, and ultrastructural characteristics of two eyes with
retinal hemangioblastoma from patients with von Hippel-Lindau and von Hippel disease. Results of histologic evaluation showed the eyes to have degenerative changes and residual
retinal hemangioblastoma. Immunohistochemical stains performed for MAC-387,
factor XIIIa,
lysozyme, alpha 1 anti-
chymotrypsin (histiocyte markers),
factor VIII-associated
antigen, ulex europeaus (endothelial markers),
neuron-specific enolase,
chromogranin, neurofilament (neuroectodermal/neural/neuroendocrine markers) and
glial fibrillary acid protein (glial marker) showed normal
retinal vascular endothelium, neurons, and glial cells to
stain where expected. Vascular endothelium in the
retinal hemangioblastomas stained for
factor VIII and ulex europeaus. Interstitial cells in the stroma of the
tumors failed to
stain for the histiocyte markers,
chromogranin, and neurofilament. The stromal cells stained for
glial fibrillary acid protein and
neuron specific enolase. Ultrastructural findings in both eyes included endothelial/pericyte-lined vascular channels, elongated stromal cells, and plump, vacuolated stromal cells with ultrastructural features consistent with glial cells. This study supports the concept that
retinal hemangioblastoma is composed of a proliferation of capillaries and glial cells.