BRAF and pilomyxoid astrocytoma: While the BRAF V600E mutation is found in about 60% of pleomorphic xanthoastrocytoma (PXA), 50% of gangliomas, 9% of PA and 2–12% glioblastoma, the KIAA1549–BRAF fusion is frequently found roughly in 50–80% of PA and pilomyxoid astrocytomas (PMA), which is an aggressive variant of PA [16].