Which molecular subtype of medulloblastoma carries the best prognosis?
- A Group 3 with MYC amplification
- B SHH-activated with TP53 mutation
- C WNT-activated ✓
- D Group 4
Correct answer: C. WNT-activated
Explanation
WNT-activated medulloblastomas carry CTNNB1 mutations, occur in older children, rarely metastasise, and have long-term survival above 90 percent. The worst prognosis belongs to Group 3 tumours with MYC amplification, which are common in infants and show early metastatic spread. SHH-activated tumours with TP53 mutation have an intermediate to poor outlook because of radiotherapy-induced second malignancies. Group 4 is the most common subtype overall with an intermediate prognosis.
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.