BRAF and pilocytic astrocytoma: The BRAF V600E mutation was observed in CNS tumors, e.g., in 66% of pleomorphic xanthoastrocytoma [26], 51% of dysembryoplastic neuroepithelial tumor [27], 18-57% of ganglioglioma [28], 5-15% of pilocytic astrocytoma [16, 17], and 1% of glioblastoma [26].