title: Evaluation of the role of pre-operative magnetic resonance imaging in the management of rectal cancer.
abstract: OBJECTIVE
  This study assesses the ability of body coil magnetic resonance imaging (MRI) to pre-operatively stage mural penetration, nodal status and circumferential resection margin (CRM) involvement of rectal cancer.
  
  
  METHODS
  Between 1995 and 1997, MRI using a body coil was performed in consecutive patients with primary rectal carcinomas. Group A: 67 patients underwent surgery without long course neo-adjuvant therapy. Predicted tumour stage was compared to the histology of the specimen. Group B: 21 patients with MRI evidence of advanced disease, underwent long course neo-adjuvant therapy followed by repeat MRI prior to surgery. The second scan assessed response to treatment and likelihood of CRM involvement at subsequent surgery.
  
  
  RESULTS
  Group A: Accuracy of pre-operative staging was: 'T' stage - 54%, 'N' stage - 77%, involvement of CRM by tumour - 97%. Group B: After long course neo-adjuvant therapy the second MRI scan was 95% accurate in predicting CRM involvement by tumour.
  
  
  CONCLUSIONS
  In this study pre-operative rectal cancer staging with MRI and a body coil lacks accuracy in predicting mural penetration and nodal involvement. Body coil MRI can accurately predict the potential for CRM involvement. This technique may help determine which patients require long course neo-adjuvant therapy.
authors.affiliation: Department of Surgery, The Centre for Digestive Diseases, The General Infirmary at Leeds, Leeds, UK. idbotterill@netscapeonline.co.uk
authors.forename: I D
authors.initials: ID
authors.lastname: Botterill
authors.forename: D M
authors.initials: DM
authors.lastname: Blunt
authors.forename: P
authors.initials: P
authors.lastname: Quirke
authors.forename: D
authors.initials: D
authors.lastname: Sebag-Montefiore
authors.forename: P M
authors.initials: PM
authors.lastname: Sagar
authors.forename: P J
authors.initials: PJ
authors.lastname: Finan
authors.forename: A G
authors.initials: AG
authors.lastname: Chalmers