Glioblastoma arising within sites of encephalomalacia from cerebrovascular insult: two cases and a review of the literature.

Glioblastoma is the most common primary parenchymal brain malignancy, with median survival of less than one year. While there are likely multiple predisposing genetic and environmental factors in glioblastoma formation, chronic inflammation resulting from non-traumatic vascular brain injury is one proposed risk factor for oncogenesis. Here, we report two instances of glioblastoma arising within areas of encephalomalacia caused by remote vascular insults (one following aneurysmal subarachnoid hemorrhage and one following ischemic infarction), review the literature associating glioblastoma with prior brain injury, and discuss potential mechanisms for malignant transformation in injured brain tissue.