A 6-year-old girl presents with hydrocephalus. MRI reveals a heterogeneous fourth ventricular mass. Histology shows uniform tumor cells arranged radially around blood vessels, with tapering processes extending toward the vessel wall. What is this specific pattern called?
- A Homer Wright rosets
- B Flexner-Wintersteiner rosets
- C Perivascular pseudorosettes ✓
- D True ependymal rosets
Correct answer: C. Perivascular pseudorosettes
Explanation
The fourth ventricular mass in a child is an ependymoma. The hallmark histological feature is the perivascular pseudorosette, where tumor cells radially arrange around blood vessels. Homer Wright rosets are seen in medulloblastoma, and Flexner-Wintersteiner rosets are seen in retinoblastoma.
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.