Brain tumor staging
WHO histologic grading for CNS tumors:
'
Grade I:
- Lesions with low proliferative potential, a frequently discrete nature, and the possibility of cure following surgical resection alone
- Juvenile pilocytic astrocytoma, subependymal giant cell astrocytoma
Grade II:
- Lesions that are generally infiltrating and low in mitotic activity but recur; some tumor types tend to progress to higher grades of malignancy
- Diffuse astrocytoma, oligodendroglioma, oligoastrocytoma
Grade III:
- Lesions with histologic evidence of malignancy, generally in the form of mitotic activity, clearly expressed infiltrative capabilities, and anaplasia
- Anaplastic astrocytoma, anaplastic oligoastrocytoma, anaplastic oligoastrocytoma
Grade IV:
- Lesions that are mitotically active, necrosis-prone, and generally associated with a rapid preoperative and postoperative evolution of disease
- Glioblastoma