title: Rosette-forming glioneuronal tumor of the fourth ventricle.
abstract: Rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle has been reported recently as a novel type of primary CNS neoplasm. We present the case of a 35-year-old male patient with RGNT of the fourth ventricle. The tumor was found incidentally; the patient did not suffer from any neurological symptoms. The tumor mass involved the caudal cerebellar vermis, filled the fourth ventricle and protruded into the caudal part of the mesencephalic aquaeduct. Smaller tumor nodules were visible in the adjacent right cerebellar hemisphere. Histologically, prominent neurocytic rosettes with synaptophysin expression were embedded in a glial tumor component resembling pilocytic astrocytoma. Clinicopathological features of our case closely resemble those reported in the original description. Thus, our case confirms RGNT as a new distinct type of primary CNS neoplasm. Due to its distinct features, adoption of RGNT as a new entity into the WHO classification of tumors should be considered.
authors.affiliation: Institute of Neurology, University of Vienna, AKH 4J, Währinger Gürtel 18-20, POB 48, 1097, Vienna, Austria.
authors.forename: Matthias
authors.initials: M
authors.lastname: Preusser
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dietrich
authors.forename: Thomas
authors.initials: T
authors.lastname: Czech
authors.forename: Daniela
authors.initials: D
authors.lastname: Prayer
authors.forename: Herbert
authors.initials: H
authors.lastname: Budka
authors.forename: Johannes A
authors.initials: JA
authors.lastname: Hainfellner
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D020546:Fourth Ventricle / Q000378:metabolism / Q000473:pathology*; D018303:Ganglioglioma / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D018396:Mucin-1 / Q000378:metabolism; D016900:Neurofilament Proteins / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism / Q000473:pathology; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D012397:Rosette Formation; D013194:Staining and Labeling; D016708:Synaptophysin / Q000378:metabolism; D014746:Vimentin / Q000378:metabolism
chemical_list: D005904:Glial Fibrillary Acidic Protein; D019394:Ki-67 Antigen; D018396:Mucin-1; D016900:Neurofilament Proteins; D016708:Synaptophysin; D014746:Vimentin; D010751:Phosphopyruvate Hydratase