title: Accuracy of multidetector computed tomography in identifying poor prognostic factors in colonic cancer.
abstract: BACKGROUND
  Recent neoadjuvant strategies for high-risk colonic tumours have renewed interest in accurate preoperative staging. The aim of this study was to validate prospectively the accuracy of multidetector computed tomography (MDCT) in stratifying patients into good and poor prognostic groups in a multicentre setting.
  
  
  METHODS
  Staging MDCT scans of 84 patients with colonic cancer were reviewed by two independent radiologists and stratified into low-risk (T1/T2 and T3 with extramural tumour depth (EMD) of less than 5 mm) and high-risk (T3 with EMD of at least 5 mm and T4) tumours. Nodal status and extramural venous invasion (EMVI) were also assessed.
  
  
  RESULTS
  The accuracy, sensitivity, specificity and positive predictive value of stratification by CT compared with histological examination was 74 (95 per cent confidence interval 64 to 82), 78 (65 to 87), 67 (49 to 81) and 81 (68 to 89) per cent respectively. Accuracy for detecting malignant lymph nodes and EMVI was 58 and 70 per cent respectively. The agreement for predicting prognostic stratification was moderate (kappa = 0.54).
  
  
  CONCLUSIONS
  As the ability of CT to identify node status is poor, the depth of tumour invasion beyond the muscularis propria is the most accurate way to identify patients with a poor prognosis who may be suitable for neoadjuvant treatment.
authors.affiliation: Department of Surgery, Mayday University Hospital, Croydon, UK.
authors.forename: S
authors.initials: S
authors.lastname: Dighe
authors.forename: H
authors.initials: H
authors.lastname: Blake
authors.forename: M-D
authors.initials: MD
authors.lastname: Koh
authors.forename: I
authors.initials: I
authors.lastname: Swift
authors.forename: A
authors.initials: A
authors.lastname: Arnaout
authors.forename: L
authors.initials: L
authors.lastname: Temple
authors.forename: Y
authors.initials: Y
authors.lastname: Barbachano
authors.forename: G
authors.initials: G
authors.lastname: Brown
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000000981:diagnostic imaging / Q000473:pathology; D009367:Neoplasm Staging; D015588:Observer Variation; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards*