WHO grading of astrocytomas

The WHO grading system is currently most widely used for grading of astrocytomas. The last revision was published in 2007. It has four cathegories.

Grade Description Types
Grade I slow growing, benign, localised pilocytic astrocytoma, xanthoastrocytoma, subependymal giant cell astrocytoma, subependymoma
Grade II low grade, infiltrative, slow-growing low-grade (fibrillary) astrocytoma, mixed oligoastrocytoma
Grade III anaplastic, infiltrative anaplastic astrocytoma
Grade IV glioblastoma, necrosis glioblastoma multiforme


1. Louis DN, Ohgaki H, Wiestler OD, Cavenee WK, Burger PC, Jouvet A, et al. The 2007 WHO classification of tumours of the central nervous system. Acta Neuropathol. 2007 Aug;114(2):97–109.