title: Positron emission tomography of schwannomas: emphasizing its potential in preoperative planning.
abstract: OBJECTIVE
  In this article, we describe FDG uptake in schwannoma as measured on positron emission tomography (PET). FDG uptake is compared with tumor cellularity, tumor size, and tumor proliferation rate (Ki-67 index).
  
  
  CONCLUSIONS
  Schwannomas generally have a high tumor-to-background ratio on FDG PET. Semiquantitative analysis with standardized uptake values (SUVs) reveals a wide variation in SUVs that can be explained by variations in the degree of cellularity. No correlation was found between FDG uptake and tumor size or tumor proliferation rate (Ki-67 index). Because these tumors often have a high level of FDG uptake, distinguishing schwannomas from malignant peripheral nerve sheath tumors before biopsy or surgery is not possible. Even in cases in which the maximum SUV or average SUV is greater than 6.0, schwannomas cannot be excluded. Therefore, schwannoma should be included in the differential diagnosis of peripheral nerve sheath tumors with low, intermediate, or high SUVs.
authors.affiliation: Department of Radiology, Division of Nuclear Medicine, Box 356113, University of Washington Medical Center, 1959 NE Pacific St., Seattle, WA 98195, USA.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Beaulieu
authors.forename: Brian
authors.initials: B
authors.lastname: Rubin
authors.forename: David
authors.initials: D
authors.lastname: Djang
authors.forename: Ernest
authors.initials: E
authors.lastname: Conrad
authors.forename: Eric
authors.initials: E
authors.lastname: Turcotte
authors.forename: Janet F
authors.initials: JF
authors.lastname: Eary
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D011300:Preoperative Care; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D014055:Tomography, Emission-Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18