Neoplastic growth of cerebral cavernous malformation presenting with impending cerebral herniation: a case report and review of the literature on de novo growth of cavernomas.

BACKGROUND: Cerebral cavernomas are rare vascular anomalies and their expansile growth has been considered to be mainly due to recurrent hemorrhages. They are not generally reported to show aggressive behavior. CASE DESCRIPTION: A 27-year-old male presented with headache, visual disturbances, and a 17-year history of seizures. He was known to have a temporal lobe lesion on CT scan, consistent with a diagnosis of cavernous malformation but with no relevant family history. Serial clinical and radiological follow-up revealed a progressive increase in the size of the lesion with formation of a growing cyst of 7 cm in diameter, which produced mass effect, resulting in the clinical picture of cerebral herniation. The patient underwent emergency surgical resection with symptomatic relief. There was no evidence of significant hemorrhage at surgery.
CONCLUSION: Cavernous malformations can show expansile growth without any evidence of a presaging hemorrhagic event and, in the manner of a neoplastic lesion, present with raised intracranial pressure and cerebral herniation.