BRAF and pilomyxoid astrocytoma: All KIAA1549::BRAF fusion-positive LGGs were confirmed to have a PA (N = 158), pilomyxoid astrocytoma (PMA, N = 9), mixed pilocytic/pilomyxoid astrocytoma (N = 2), or fibrillary astrocytoma (N = 3) diagnosis (Figure S3).