A 45-year-old man has a brain tumor showing pseudopalisading necrosis, microvascular proliferation, and pleomorphic glial cells. The molecular profile of IDH-wildtype glioblastoma includes:

• A IDH1/IDH2 mutation with 1p/19q co-deletion
• B EGFR amplification, PTEN loss, and TERT promoter mutation ✓
• C BRAF V600E mutation
• D NF2 mutation with loss of merlin

Explanation

Glioblastoma (WHO grade 4) is defined by pseudopalisading necrosis, microvascular proliferation, and pleomorphism. Primary (de novo) IDH-wildtype glioblastoma typically shows EGFR amplification, PTEN loss, and TERT promoter mutation — conferring very poor prognosis. IDH mutation with 1p/19q codeletion defines oligodendroglioma (better prognosis). BRAF V600E is in pediatric low-grade gliomas; NF2 mutation is in meningioma and schwannoma.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.