Rosette-forming glioneuronal tumors (RGNT) of the fourth ventricle are rare mixed glio-neuronal tumors included in the revised WHO classification of CNS tumors and show histopathological features similar to pilocytic astrocytomas. To evaluate at molecular level potential affinities between these tumors, we investigated a case of RGNT, arising in the cerebellum of a young patient, for the presence of transcriptional products originating from the KIAA1549-BRAF fusion. However, the analysis did not show any fusion. Further studies in larger RGNT case series are needed in order to demonstrate the possible presence of KIAA1549-BRAF fusion and better delineate its relationship with pilocytic astrocytomas.
© 2011 Japanese Society of Neuropathology.