title: PET/CT in the assessment of previously treated skull base malignancies.
abstract: BACKGROUND
  Altered anatomy, radiotherapy, hardware, and reconstructive materials distort the posttreatment ventral skull base. The diagnostic characteristics of positron emission tomography/CT (PET/CT) studies in those with suspected recurrent malignancy were assessed.
  
  
  METHODS
  A retrospective review was undertaken of patients with head and neck cancer who had PET/CT for ventral skull base disease.
  
  
  RESULTS
  Thirty-four PET/CTs were performed for suspected recurrent malignancy in the skull base (mean age, 59.6 +/- 10.7 years; female 38%). The group comprised mainly minor salivary (35.3%), squamous (32.3%), and neuroectodermal (23.6%) tumors. Mean clinical follow-up after PET/CT was 256 +/- 173 days. Sensitivity was 100% but specificity was 40%. Standard uptake values (SUVs) for true positives were higher than for those without disease (p = .03).
  
  
  CONCLUSIONS
  PET/CT is a highly sensitive test for malignant disease. The mucosal lining of the reconstructed skull base is a common source for inflammatory pathologies that may lead to false-positive PET/CT. Defining SUV thresholds for malignancy may improve specificity.
authors.affiliation: Department of Otolaryngology/Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA. richard@richardharvey.com.au
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Harvey
authors.forename: Geoff
authors.initials: G
authors.lastname: Pitzer
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Nissman
authors.forename: Luke
authors.initials: L
authors.lastname: Buchmann
authors.forename: Zoran
authors.initials: Z
authors.lastname: Rumboldt
authors.forename: Terry
authors.initials: T
authors.lastname: Day
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Schlosser
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000473:pathology; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D019291:Skull Base / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed