title: Hybrid neurofibroma/schwannoma is overrepresented among schwannomatosis and neurofibromatosis patients.
abstract: We analyzed the histologic features of peripheral nerve sheath tumors occurring in 14 patients with schwannomatosis. Among a total of 31 tumors, 19 tumors (61%) showed schwannoma-like nodules within a neurofibroma-like tumor, corresponding to hybrid neurofibroma/schwannoma. At least 1 hybrid tumor occurred in 10 of 14 (71%) schwannomatosis patients. We then retrieved cases of hybrid tumors without documented relation to schwannomatosis from our database and identified 41 tumors arising in 23 patients. More than half of these patients (14/23) were reported to suffer from multiple peripheral nerve sheath tumors, favoring a tumor syndrome. Indeed, analysis of clinical records revealed the diagnosis of neurofibromatosis type 2 (NF2) in 26% (6/23), neurofibromatosis type 1 (NF1) in 9% (2/23), definite schwannomatosis in 4% (1/23), and possible schwannomatosis in 13% (3/23) of patients with multiple nerve sheath tumors. Our findings suggest that hybrid neurofibroma/schwannoma represents a common tumor type in schwannomatosis and shows a striking association with neurofibromatoses.
authors.affiliation: Institute of Neuropathology, University Hospital Münster, Germany. anja.harder@ukmuenster.de
authors.forename: Anja
authors.initials: A
authors.lastname: Harder
authors.forename: Martin
authors.initials: M
authors.lastname: Wesemann
authors.forename: Christian
authors.initials: C
authors.lastname: Hagel
authors.forename: Jens
authors.initials: J
authors.lastname: Schittenhelm
authors.forename: Susan
authors.initials: S
authors.lastname: Fischer
authors.forename: Marcos
authors.initials: M
authors.lastname: Tatagiba
authors.forename: Christoph
authors.initials: C
authors.lastname: Nagel
authors.forename: Astrid
authors.initials: A
authors.lastname: Jeibmann
authors.forename: Axel
authors.initials: A
authors.lastname: Bohring
authors.forename: Victor-Felix
authors.initials: VF
authors.lastname: Mautner
authors.forename: Werner
authors.initials: W
authors.lastname: Paulus
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000378:metabolism / Q000473:pathology*; D009455:Neurofibroma / Q000378:metabolism / Q000473:pathology; D017253:Neurofibromatoses / Q000378:metabolism / Q000473:pathology*; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor