title: Clinical utility of PET/CT in the evaluation of head and neck squamous cell carcinoma with an unknown primary: a prospective clinical trial.
abstract: BACKGROUND
  Metastatic head and neck squamous cell carcinoma with an unknown primary is an uncommon but important problem. PET/CT, as an adjunct to diagnosis, is potentially useful but has never been studied in a prospective, single-blinded clinical trial.
  
  
  METHODS
  In all, 20 subjects with cervical metastases from an unknown head and neck primary were enrolled in a prospective clinical trial. A standard protocol was used in both clinic and operating room (OR). Study surgeons were blinded to the PET/CT result upon completion of the standard work-up.
  
  
  RESULTS
  PET/CT increased the detection of a primary site from 25% to 55% (5 vs 11 subjects). This difference was statistically and clinically significant (p = .03, McNemar's test). There was 1 false negative PET/CT scan.
  
  
  CONCLUSIONS
  An unknown primary should be diagnosed only after a complete head and neck examination, flexible endoscopy, and CT or MRI. PET/CT performed prior to panendoscopy will increase the diagnostic yield in the unknown head and neck primary population, leading to more targeted, and less morbid, treatment.
authors.affiliation: Division of Otolaryngology-Head & Neck Surgery, Department of Surgery, University of Calgary, Calgary, Canada.
authors.forename: Luke
authors.initials: L
authors.lastname: Rudmik
authors.forename: Harold Y
authors.initials: HY
authors.lastname: Lau
authors.forename: T Wayne
authors.initials: TW
authors.lastname: Matthews
authors.forename: J Douglas
authors.initials: JD
authors.lastname: Bosch
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kloiber
authors.forename: Christine P
authors.initials: CP
authors.lastname: Molnar
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Dort
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000556:secondary*; D005260:Female; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000556:secondary; D006801:Humans; D008297:Male; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary / Q000175:diagnosis*; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D057234:Preoperative Period; D011446:Prospective Studies; D000077195:Squamous Cell Carcinoma of Head and Neck; D014057:Tomography, X-Ray Computed