In the WHO CNS5, pDLGG is classified into four distinct tumor types, namely, (1) diffuse astrocytoma, MYB- or MYBL1-altered; (2) angiocentric glioma (AG); (3) polymorphous low-grade neuroepithelial tumor of the young (PLNTY); and (4) diffuse low-grade glioma, MAPK pathway-altered (Table 1). This evidence concerns the gene MYBL1 and diffuse astrocytoma.