Background: The ability of vascular anomalies to induce neoplastic transformation in normal brain parenchyma has been suggested but not demonstrated. We present a novel case in which a patient with a pre-existing cavernous malformation developed an adjacent ependymoma.
Case description: A 72-year-old man developed an anaplastic ependymoma at the site of a pre-existing cavernous malformation. This is the first documented instance of an ependymoma developing at the site of an existing cavernous malformation. The colocalization of both lesions and the low incidence of supratentorial ependymomas in this age group makes it unlikely that their coexistence represents a random event. Immunohistochemistry demonstrated vascular endothelial growth factor (VEGF) production by the cavernous malformation and robust VEGF receptor expression by the ependymoma.
Conclusions: Based on these findings, we suggest that production of VEGF by vascular malformations may play a role in the neoplastic transformation of adjacent tissue.