Professional
Technical
IVT
WHO grade
The World Health Organization's standardized classification system for brain tumor malignancy levels from I to IV.
Full Definition
WHO grade refers to the World Health Organization's classification system for central nervous system tumors, ranging from Grade I (least malignant) to Grade IV (most malignant). This grading system is based on histological features including cellular atypia, mitotic activity, microvascular proliferation, and necrosis. Grade I tumors are typically benign with excellent prognosis, while Grade IV tumors like glioblastoma multiforme have poor prognosis. The WHO grade is a crucial prognostic indicator and guides treatment planning in neurosurgical oncology.
Usage
Usage note: Always capitalize WHO and use Roman numerals for grade levels.
In Context
- "Pathology confirmed a WHO grade II oligodendroglioma with favorable molecular markers." — Pathology report
- "The WHO grade directly influenced the adjuvant treatment recommendations." — Multidisciplinary team meeting notes
Also known as
WHO classification
histological grade
tumor grade
Don't confuse with
Karnofsky score
tumor staging
ECOG performance status