title: Clinically important detection of infection as an 'incidental' finding during cancer staging using FDG-PET/CT.
abstract: BACKGROUND
  FDG-PET/CT is widely used in the management of a variety of malignancies with excellent overall accuracy, despite the potential for false positive results related to infection and inflammation.
  
  
  OBJECTIVE
  As cancer patients can develop clinically inapparent infections, we evaluated the prevalence and nature of incidental findings reported to be suggestive of infections that had been identified during clinical cancer staging with FDG-PET/CT.
  
  
  METHODS
  The study involved a retrospective analysis of 60 patients managed primarily at our facility from a total of 121 cases identified as having possible infection on clinical reporting of more than 4500 cancer staging investigations performed during the calendar year of 2008.
  
  
  RESULTS
  Occult infections were uncommon overall (≤1%), but most often because of pneumonia (31.6%), upper respiratory tract infections (21.1%) or wound infections (15.8%). Abnormal scans contributed to patients' management in 52.7% of cases. Two out of 13 patients whose scan abnormalities were not investigated further had worsening changes on repeated scan and one of these patients had clinical deterioration.
  
  
  CONCLUSIONS
  In patients with FDG-PET/CT scans suggestive of infection and in whom a final diagnosis could be reached, the positive predictive value for FDG-PET/CT scans was 89% suggesting that abnormal scans indicative of infection should be investigated further in this population.
authors.affiliation: Department of Medicine, Hospital Pulau Pinang, Pulau Pinang, Malaysia. drwongps@yahoo.com
authors.forename: P S
authors.initials: PS
authors.lastname: Wong
authors.forename: W F E
authors.initials: WF
authors.lastname: Lau
authors.forename: L J
authors.initials: LJ
authors.lastname: Worth
authors.forename: K A
authors.initials: KA
authors.lastname: Thursky
authors.forename: E
authors.initials: E
authors.lastname: Drummond
authors.forename: M A
authors.initials: MA
authors.lastname: Slavin
authors.forename: R J
authors.initials: RJ
authors.lastname: Hicks
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D009367:Neoplasm Staging / Q000379:methods*; D049268:Positron-Emission Tomography; D012141:Respiratory Tract Infections / Q000000981:diagnostic imaging* / Q000453:epidemiology; D014057:Tomography, X-Ray Computed; D014946:Wound Infection / Q000000981:diagnostic imaging* / Q000453:epidemiology; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18