title: Hybrid peripheral nerve sheath tumors, including a malignant variant in type 1 neurofibromatosis.
abstract: The authors report a small case series of hybrid nerve sheath tumors occurring in the setting of type 1 neurofibromatosis. Four lesions were benign and consisted of plexiform neurofibromas with considerable areas of perineuriomatous differentiation in patients with type 1 neurofibromatosis. In these lesions, biphasic (Schwannian and perineuriomatous) differentiation was apparent on immunohistochemistry, with the perineuriomatous areas staining for epithelial membrane antigen, glut-1, and claudin-1 and being negative for S-100 protein. Three patients were members of a single family, with a history of various malignant neoplasms. Included in the series is 1 hybrid lesion in which neurofibromatous and perineuriomatous areas were clearly visible on hematoxylin- and eosin-stained slides. The lesion was unique in that it manifested malignant change in the S-100 protein-positive component, which was classified as malignant peripheral nerve sheath tumor. The malignant component showed areas with an epithelioid cell morphology.
authors.affiliation: Sikl's Department of Pathology, Charles University in Prague, Faculty of Medicine in Pilsen, Pilsen, Czech Republic. kazakov@medima.cz
authors.forename: Denisa
authors.initials: D
authors.lastname: Kacerovska
authors.forename: Michal
authors.initials: M
authors.lastname: Michal
authors.forename: Naoto
authors.initials: N
authors.lastname: Kuroda
authors.forename: Azusa
authors.initials: A
authors.lastname: Tanaka
authors.forename: Radek
authors.initials: R
authors.lastname: Sima
authors.forename: Natalja
authors.initials: N
authors.lastname: Denisjuk
authors.forename: Boris
authors.initials: B
authors.lastname: Kreuzberg
authors.forename: Renata
authors.initials: R
authors.lastname: Ricarova
authors.forename: Dmitry V
authors.initials: DV
authors.lastname: Kazakov
mesh_terms: D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D002454:Cell Differentiation; D015622:Epithelioid Cells / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D018317:Nerve Sheath Neoplasms / Q000737:chemistry / Q000473:pathology*; D009456:Neurofibromatosis 1 / Q000378:metabolism / Q000473:pathology*; D012583:Schwann Cells / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor