title: Diagnostic performance of fluorine-18-fluorodeoxyglucose positron emission tomography in patients with Merkel cell carcinoma: a systematic review and meta-analysis.
abstract: BACKGROUND
  Some studies reported the usefulness of fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and PET/computed tomography (CT) in patients with Merkel cell carcinoma (MCC).
  
  
  OBJECTIVE
  The aim of this study was to systematically review and meta-analyze published data about the diagnostic performance of 18F-FDG PET and PET/CT in patients with MCC.
  
  
  METHODS
  A comprehensive literature search of studies published through June 2013 regarding 18F-FDG PET and PET/CT in patients with MCC was performed. All retrieved studies were reviewed and qualitatively analyzed. Pooled sensitivity, specificity, positive and negative likelihood ratio (LR+ and LR−) and diagnostic odds ratio (DOR) of 18F-FDG PET or PET/CT in patients with MCC on a per examination-based analysis were calculated. The area under the summary receiver operating characteristic (ROC) curve was calculated to measure the accuracy of 18F-FDG PET or PET/CT in these patients.
  
  
  RESULTS
  Ten studies comprising 329 patients (549 scans) with MCC were included in the qualitative analysis (systematic review) and discussed. The quantitative analysis (meta-analysis) of six selected studies (including 92 patients with MCC) provided the following results on a per examination-based analysis: sensitivity was 90 % (95 % CI 80–96), specificity 98 % (95 % CI 90–100), LR+ 12 (95 % CI 4.3–33.0), LR− 0.15 (95 % CI 0.08–0.28), and DOR 86.8 (95 % CI 23–327). The area under the summary ROC curve was 0.96. No significant statistical heterogeneity between the studies was found.
  
  
  CONCLUSIONS
  In patients with MCC, 18F-FDG PET or PET/CT demonstrated high sensitivity and specificity, being accurate methods in this setting. Nevertheless, the literature focusing on the use of PET and PET/CT in MCC still remains limited. Prospective studies are needed to substantiate the high diagnostic accuracy of these methods in MCC.
authors: Giorgio
authors: G
authors: Treglia
authors: Vahid Reza Dabbagh
authors: VR
authors: Kakhki
authors: Luca
authors: L
authors: Giovanella
authors: Ramin
authors: R
authors: Sadeghi
mesh_terms: D015266:Carcinoma, Merkel Cell / Q000175:diagnosis* / Q000473:pathology; D019788:Fluorodeoxyglucose F18; D006801:Humans; D016013:Likelihood Functions; D049268:Positron-Emission Tomography / Q000379:methods*; D012372:ROC Curve; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18