High-grade astroblastoma initially misdiagnosed as papillary meningioma: a case report.

Astroblastoma is a well-circumscribed glial neoplasm that typically occurs in the cerebral hemisphere of children and young adults, usually presenting with symptoms of increased intracranial pressure such as headaches, vomiting, and seizures. It is characterized histologically by papillary or pseudopapillary architecture, astroblastic pseudorosettes, vascular hyalinization, and lack of fibrillarity. However, these morphological features are not considered pathognomonic to astroblastomas and may be encountered in several central nervous system tumors, such as ependymoma and papillary meningioma, complicating the diagnostic process. In this report, we describe the case of an astroblastoma in an 18-year-old male presenting with symptoms of intracranial hypertension. Imagery revealed a right cerebral hemispheric mass with a particularly misleading fronto-ethmoidal dural attachment, which, in conjunction with the deceptive papillary architecture, prompted the initial misdiagnosis of papillary meningioma on two consecutive occasions before diagnostic revision. This article aims to highlight the main reasons for this diagnostic confusion, along with providing key clinical, radiological, histological, and molecular features of relevance to the differential diagnostic approach.