title: Combined multimodal co-registration of PET/CT and MRI images increases diagnostic accuracy in squamous cell carcinoma staging.
abstract: OBJECTIVE
  The purpose of our study was to assess the diagnostic value of multi-modal imaging through co-registration of short tau inversion recovery (STIR) and diffusion-weighted imaging (DWI) MRI with (18)FDG-PET/CT in T and N staging of head and neck tumours.
  
  
  METHODS
  25 patients with head and neck squamous cell carcinoma who had undergone MRI and PET/CT before treatment were retrospectively evaluated. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PET/CT, MRI and their combined use were assessed in T and N staging. Histopathology and follow-up imaging results were used as the gold standard.
  
  
  RESULTS
  In assessing trans-compartmental extensions, PET-MRI showed 93 % sensitivity, 88 % specificity, 94 % PPV, and 88 % NPV, as compared to the 94 and 53 % sensitivity, 75 and 75 % specificity, 89 and 82 % PPV, and 86 and 43 % demonstrated by MRI and PET, respectively. In the identification of pathological lymph nodes, PET-MRI showed 92 % sensitivity, 89 % specificity, 96 % PPV, and 89 % NPV, whereas PET/CT displayed 72 % sensitivity, 89 % specificity, 95 % PPV and 53 % NPV. The corresponding figures for DWI and STIR sequences were 84 and 100 % sensitivity, 67 and 56 % specificity, 88 and 86 % PPV, and 60 and 100 % NPV, respectively.
  
  
  CONCLUSIONS
  Multi-modal imaging assessment of co-registered MRI and PET/CT images provides more accurate results for trans-compartmental extensions in T and N staging than the individual techniques alone.
authors.affiliation: Radiology Department, University of Eastern Piedmont, "Maggiore della Carità" Hospital, Corso Mazzini 18, 28100, Novara, Italy. a.stecco@libero.it.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Stecco
authors.affiliation: Radiology Department, University of Eastern Piedmont, "Maggiore della Carità" Hospital, Corso Mazzini 18, 28100, Novara, Italy.
authors.forename: Silvio
authors.initials: S
authors.lastname: Ciolfi
authors.affiliation: Radiology Department, University of Eastern Piedmont, "Maggiore della Carità" Hospital, Corso Mazzini 18, 28100, Novara, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Buemi
authors.affiliation: Radiology Department, University of Eastern Piedmont, "Maggiore della Carità" Hospital, Corso Mazzini 18, 28100, Novara, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Cassarà
authors.affiliation: Nuclear Medicine Department, University of Eastern Piedmont, "Maggiore della Carità" Hospital, Novara, Italy.
authors.forename: Gian Mauro
authors.initials: GM
authors.lastname: Sacchetti
authors.affiliation: Medical Physics Department, University of Eastern Piedmont, "Maggiore della Carità" Hospital, Novara, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Brambilla
authors.affiliation: Radiology Department, University of Eastern Piedmont, "Maggiore della Carità" Hospital, Corso Mazzini 18, 28100, Novara, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Carriero
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D009367:Neoplasm Staging; D000072078:Positron Emission Tomography Computed Tomography; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
keywords: Co-registration; MRI; PET-MRI; PET/CT; SCC