neuroepithelial neoplasm neuronal tumor Neuronal brain tumors are an uncommon group of central nervous system tumors that arise from cells with neuronal differentiation. These tumors may be purely neuronal in origin or have mixed neuronal and glial components, which comprise a subset of glioneuronal tumors. Orphanet:251924 UMLS:CN201974 Term added in response to Mondo restructuring. To be considered for replacement or obsoletion in EFO also.