A glioma with an arteriovenous malformation: an association or a different entity?

A 58-year-old male was admitted with headache to our neurosurgery clinic. His neurological examination revealed slight left hemiparesis. The radiological evaluation with contrast administred magnetic resonance imaging (MRI) scan demonstrated a right temporo-parietal ring enhancing mass lesion surrounded by edema which was resembling a typical glioma (Fig. 1). The patient was operated on via a temporo-parietal craniotomy and an arteriovenous malformation surrounded by abnormal glial tissue was observed during the exposure. A nidus supplied by several branches arising from the middle cerebral artery (MCA) was obvious. The venous drainage of the malformation was to the superficial venous system. The observed arterial feeders and the draining vein were coagulated and the nidus was macroscopically totally excised. The frozen examination from surrounding glial tissue revealed a high grade glioma. The tumor was also macroscopically totally excised. Postoperatively, the cerebral angiogram demonstrated a right temporal arteriovenous malformation with a centrally excised nidus. The remaining major feeders involved the angular gyrus and the posterior temporal arteries. The venous drainage was to the straight and sigmoid sinuses (Fig. 2). The final histopathological examination of the specimen revealed an arteriovenous malformation surrounded by a high grade glioma (Fig. 3). The patient refused a second operation for total removal of the AVM. Postoperatively, he is doing well with improvement of his left hemiparesis.