title: Head and neck squamous cell carcinoma (HNSCC)--detection of synchronous primaries with (18)F-FDG-PET/CT.
abstract: OBJECTIVE
  The aim of the study was to evaluate (18)F-FDG-PET/CT for the detection of synchronous primaries at initial staging of patients with head and neck squamous cell carcinoma (HNSCC).
  
  
  METHODS
  FDG-PET/CT images acquired between March 2001 and October 2007 in 589 consecutive patients (147 women, 442 men; mean age 61.5 years, age range 32-97 years) with proven HNSCC were reviewed for the presence of synchronous primaries. Cytology, histology and/or clinical and imaging follow-up served as reference standard.
  
  
  RESULTS
  FDG-PET/CT showed 69 suspected synchronous primaries in 62 patients of which 56 were finally confirmed in 44 patients. Of the 56 second cancers, 46 (82%) were found in the aerodigestive tract in the following locations: lung (26, 46%), head and neck (15, 17%), oesophagus (5, 9%). Ten second cancers (18%) were located outside the aerodigestive tract (colon, five; stomach, lymphoma, breast, thymus and kidney, one each). Six patients had three synchronous primaries and three patients had four synchronous cancers. Nine synchronous cancers were not detected by PET/CT (four head and neck, two lung, two oesophageal, one gastric). False-positive PET/CT findings were mainly related to benign FDG uptake in the intestine due to benign or precancerous polyps or physiological FDG uptake in other head and neck regions. Overall the prevalence of synchronous second primaries according to the reference standard was 9.5%, of which 84% were detected with FDG-PET/CT. In 80% of the patients, therapy was changed because of the detection of a synchronous primary.
  
  
  CONCLUSIONS
  FDG-PET/CT detects a considerable number of synchronous primaries (8.0% prevalence) at initial staging of patients with HNSCC. Synchronous cancers were predominantly located in the aerodigestive tract, primarily in the lung, head and neck and oesophagus. Detection of second primaries has an important impact on therapy. PET/CT should be performed before panendoscopy.
authors.affiliation: Division of Nuclear Medicine, Department of Medical Radiology, University Hospital Zurich, Zurich, Switzerland. klaus.strobel@usz.ch
authors.forename: Klaus
authors.initials: K
authors.lastname: Strobel
authors.forename: Stephan K
authors.initials: SK
authors.lastname: Haerle
authors.forename: Sandro J
authors.initials: SJ
authors.lastname: Stoeckli
authors.forename: Madeleine
authors.initials: M
authors.lastname: Schrank
authors.forename: Jan D
authors.initials: JD
authors.lastname: Soyka
authors.forename: Patrick
authors.initials: P
authors.lastname: Veit-Haibach
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Hany
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005189:False Positive Reactions; D005260:Female; D019788:Fluorodeoxyglucose F18; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009378:Neoplasms, Multiple Primary / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D016609:Neoplasms, Second Primary / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D018307:Neoplasms, Squamous Cell / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18