title: Functional imaging of head and neck squamous cell carcinoma with diffusion-weighted MRI and FDG PET/CT: quantitative analysis of ADC and SUV.
abstract: OBJECTIVE
  Head and neck squamous cell carcinoma (HNSCC) may cause a decreased apparent diffusion coefficient (ADC) on diffusion-weighted magnetic resonance imaging (DW MRI) and an increased standardized uptake value (SUV) on fluorodeoxyglucose (FDG) positron emission tomography (PET/CT). We analysed the reproducibility of ADC and SUV measurements in HNSCC and evaluated whether these biomarkers are correlated or independent.
  
  
  METHODS
  This retrospective analysis of DW MRI and FDG PET/CT data series included 34 HNSCC in 33 consecutive patients. Two experienced readers measured tumour ADC and SUV values independently. Statistical comparison and correlation with histopathology was done. Intra- and inter-observer agreement for ADC and SUV measurements was assessed.
  
  
  RESULTS
  Intraclass correlation coefficient (ICC) analysis showed almost perfect reproducibility (>0.90) for ADCmean, ADCmin, SUVmax and SUVmean values for intra-observer and inter-observer agreement. Mean ADCmean and ADCmin in HNSCC were 1.05 ± 0.34 × 10(-3) mm(2)/s and 0.65 ± 0.29 × 10(-3) mm(2)/s, respectively. Mean SUVmean and mean SUVmax were 7.61 ± 3.87 and 12.8 ± 5.0, respectively. Although statistically not significant, a trend towards higher SUV and lower ADC was observed with increasing tumour dedifferentiation. Pearson's correlation analysis showed no significant correlation between ADC and SUV measurements (r -0.103, -0.051; p 0.552, 0.777).
  
  
  CONCLUSIONS
  Our data suggest that ADC and SUV values are reproducible and independent biomarkers in HNSCC.
authors: Department of Radiology, Geneva University Hospital, Geneva 14, Switzerland.
authors: Arthur
authors: A
authors: Varoquaux
authors: Olivier
authors: O
authors: Rager
authors: Karl-Olof
authors: KO
authors: Lovblad
authors: Karen
authors: K
authors: Masterson
authors: Pavel
authors: P
authors: Dulguerov
authors: Osman
authors: O
authors: Ratib
authors: Christoph D
authors: CD
authors: Becker
authors: Minerva
authors: M
authors: Becker
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D002454:Cell Differentiation; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000494:pharmacology*; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D015588:Observer Variation; D011877:Radionuclide Imaging; D012008:Recurrence; D015203:Reproducibility of Results; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D019788:Fluorodeoxyglucose F18