AstrocytomaOptic Nerve NeoplasmsHypothalamic NeoplasmsBrain NeoplasmsCerebellar NeoplasmsInfratentorial NeoplasmsCranial Nerve NeoplasmsGenes, Neurofibromatosis 1Neurofibromatosis 1Neurofibromin 1GliomaGlioblastomaOligodendrogliomaImmunohistochemistryThalamic DiseasesBrain Stem NeoplasmsOptic ChiasmEpendymomaAntineoplastic ProtocolsCentral Nervous System NeoplasmsHypothalamus, AnteriorProto-Oncogene Proteins B-rafCraniopharyngiomaSupratentorial NeoplasmsGangliogliomaAnaplasiaSpinal Cord NeoplasmsMagnetic Resonance ImagingTumor Markers, BiologicalMeningiomaImmunoenzyme TechniquesNeoplasm GradingGene Expression Regulation, NeoplasticComparative Genomic HybridizationGene DosageDNA, NeoplasmNimustineTuberous SclerosisMeningeal NeoplasmsChromosomes, Human, Pair 19BrainReverse Transcriptase Polymerase Chain ReactionIsocitrate Dehydrogenase