title: Preoperative rectal cancer staging with phased-array MR.
abstract: BACKGROUND
  We retrospectively reviewed magnetic resonance (MR) images of 96 patients with diagnosis of rectal cancer to evaluate tumour stage (T stage), involvement of mesorectal fascia (MRF), and nodal metastasis (N stage).Our gold standard was histopathology.
  
  
  METHODS
  All studies were performed with 1.5-T MR system (Symphony; Siemens Medical System, Erlangen, Germany) by using a phased-array coil. Our population was subdivided into two groups: the first one, formed by patients at T1-T2-T3, N0, M0 stage, whose underwent MR before surgery; the second group included patients at Tx N1 M0 and T3-T4 Nx M0 stage, whose underwent preoperative MR before neoadjuvant chemoradiation therapy and again 4-6 wks after the end of the treatment for the re-staging of disease.Our gold standard was histopathology.
  
  
  RESULTS
  MR showed 81% overall agreement with histological findings for T and N stage prediction; for T stage, this rate increased up to 95% for pts of group I (48/96), while for group II (48/96) it decreased to 75%.Preoperative MR prediction of histologically involved MRF resulted very accurate (sensitivity 100%; specificity 100%) also after chemoradiation (sensitivity 100%; specificity 67%).
  
  
  CONCLUSIONS
  Phased-array MRI was able to clearly estimate the entire mesorectal fat and surrounding pelvic structures resulting the ideal technique for local preoperative rectal cancer staging.
authors.affiliation: Department of Diagnostic Radiology, University of Pisa, Via Roma 67, 56100-Pisa, Italy. s.giusti@med.unipi.it
authors.forename: Sabina
authors.initials: S
authors.lastname: Giusti
authors.forename: Piero
authors.initials: P
authors.lastname: Buccianti
authors.forename: Maura
authors.initials: M
authors.lastname: Castagna
authors.forename: Elena
authors.initials: E
authors.lastname: Fruzzetti
authors.forename: Silvia
authors.initials: S
authors.lastname: Fattori
authors.forename: Elisa
authors.initials: E
authors.lastname: Castelluccio
authors.forename: Davide
authors.initials: D
authors.lastname: Caramella
authors.forename: Carlo
authors.initials: C
authors.lastname: Bartolozzi
mesh_terms: D005205:Fascia / Q000473:pathology*; D006801:Humans; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D009367:Neoplasm Staging; D011300:Preoperative Care; D012004:Rectal Neoplasms / Q000473:pathology*; D012189:Retrospective Studies