Figure 3

Histological findings of the excised specimen. A. Hematoxylin and eosin staining (×40). Hematoxylin and eosin staining (×40). The tumor consisted of varying hypertrophic peripheral nerve fascicules showing a plexiform pattern, along with fibrous connective tissues.B. Hematoxylin and eosin staining (×100). Hematoxylin and eosin staining (×100). Antoni A areas, which composed main part of the tumor. A nuclear palisading pattern was focally observed. C. Masson trichrome staining (×100). Masson trichrome staining (×100). The fibrous connective tissues around the tumor were roughly stained. Immunohistochemistry for S-100 protein (×100). Immunohistochemistry for S-100 protein (×100). The tumor cells were strongly positive for S-100 protein.