ABSTRACT
Papillary glioneuronal tumor (PGNT) most commonly occurs in the cerebral hemisphere, including the frontal lobe, temporal lobe, parietal lobe, and periventricular site. Although PGNT mainly manifests in young adults, it has occurred in a wide range of ages, including children and the elderly. The rarity of PGNT and scarcity of tissue for genetic or molecular analysis accounts for the as-yet poor understanding of its biological behavior. Patients with PGNT often present with headaches, seizures, nausea/vomiting, visual disturbance, speech disturbance, hemiparesis, loss of consciousness, vertigo/ataxia, or no symptoms. PGNT does not harbor cytogenetic alterations, as observed in conventional glial tumors. Radiologically, the differential diagnosis includes all tumors that may present with a cystic component and mural nodule, for example, pilocytic astrocytoma, ganglioglioma, dysembryoplastic neuroepithelial tumor (DNET), and ependymoma. Histologically, the differential diagnosis includes ganglioglioma and central neurocytoma. The presence of pseudopapillary structures and hyalinized blood vessels are suggestive of PGNT, as described by Komori.
