A 60-year-old woman presents with progressive headache, seizures, and right-sided weakness. MRI shows a well-circumscribed, homogeneously enhancing dural-based mass with a dural tail sign. Histology shows whorled pattern of meningothelial cells with psammoma bodies. Which of the following is the correct CNS WHO grade for a typical meningioma with these features?

• A CNS WHO grade 4
• B CNS WHO grade 2
• C CNS WHO grade 3
• D CNS WHO grade 1 ✓

Explanation

Meningioma is the most common primary brain tumor, arising from arachnoid cap cells. The typical meningioma with whorls, psammoma bodies, and a meningothelial pattern without high mitotic rate or brain invasion is CNS WHO grade 1. Grade 2 (atypical) requires mitotic count of 4-19 per 10 high-power fields or brain invasion. Grade 3 (anaplastic) requires 20 or more mitoses per 10 HFP or frankly sarcomatous/carcinomatous appearance.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.