Table 2. Typical histological features of benign nerve sheath tumors: schwannoma and neurofibroma.

	Schwannoma	Neurofibroma
Cellularity	Moderate to high	Low to moderate
Cytology	Spindle cells with extensive nuclear palisading and Verocay bodies (Antoni A areas) alternating with hypocellular, loosely myxoid regions (Antoni B areas)	Wavy nuclei, focal nuclear atypia
Immunophenotype	S100+; CD34-	CD34+; S100 +/– (variable); NFTP stains residual axonal processes
Additional features	Hyalinized vessels with occasional thrombosis; degenerative areas may be histiocyte-rich with hemosiderin representing ischemic infarction	Collagenous background stroma may be myxoid