Duplication of the FGFR1 TKD has also been reported in low-grade astrocytomas more suggestive of other specific histologic entities including pilocytic astrocytoma (typically extracerebellar) and dysembryoplastic neuroepithelial tumor (DNET, Fig. 2a, b) [23, 37, 40, 60, 77]. The gene discussed is FGFR1; the disease is pilocytic astrocytoma.