1: Low magnification with central nerve surrounded by haphazard spindle cells (nerve arrowed).
2 and 3: Higher magnifications characterized by a nerve centrally with increased cellularity (Schwann cell proliferation) surrounded circumferentially by a dense band of variably haphazardly oriented bundles of extracellular matrix of low cellularity with minimal cellular pleomorphism. The cells are predominately delicate spindle cells with scant eosinophilic cytoplasm and often elongate, wavy nuclei.
4: Neurofilament immunohistochemistry: The central, remnant nerve is evident and the axons are variably swollen and thick. There is also disorganized growth.
5: Bielschowsky silver stain: Remnant nerve at the edge of the mass with variably dilated axons.