The following microscopic appearance is that of schwannoma—a nerve sheath tumor most commonly involving the cerebellopontine angle. What does the area marked with arrow represent?
A. Myxoid tissue
B. Antony A pattern
C. Schwannoma Antoni type B
D. Antony C pattern Verocay body
Ans: C. schwannoma Antoni type B
(Ref Robbins 9/e p257. 854, 8/e p1340).
- Area marked with arrow represents growth pattern.
- Here tumor is less densely cellular & consists of loose meshwork of cells, microcysts and myxoid stroma, Antoni B pattern of growth.
Schwannoma – Histopathology:
- Verocay bodies- “Nuclear-free zones” of processes lie between regions of nuclear palisading.
In Antoni Agrowth pattern:
- Elongated cells with cytoplasmic processes are arranged in fascicles in areas of moderate to high cellularity and scant stromal matrix.
In Antoni B growth pattern:
- Tumor less densely cellular & consists of a loose meshwork of cells, microcysts and myxoid stroma.