title: The incremental value of dual modality PET/CT imaging over PET imaging alone in advanced colorectal cancer.
abstract: BACKGROUND
  (18)Fluoro-2-Deoxy Glucose (18 FDG) positron emission tomography (PET) impacts upon the management of recurrent colorectal cancer (CRC) but is limited by anatomical localisation. The development of integrated positron emission and computerised tomography (PET/CT) yields high anatomical resolution combined with the PET data. We evaluate the added value of PET/CT over PET alone.
  
  
  METHODS
  Thirty-one consecutive patients had PET/CT for suspected recurrent CRC. Two blinded observers (A and B) reported images from PET alone and from integrated PET/CT. Lesion detection, lesion localisation, diagnostic certainty and impact on surgical management was assessed for each data set and then compared. The minimum clinical follow up was for 8 months (median 9.6 months) and 7 patients had histological confirmation of diagnosis.
  
  
  RESULTS
  Compared to PET alone, PET/CT the percentage of lesions accurately localised increased from 96% to 99% for observer A and 86% to 99% for Observer B. PET/CT increased the number of lesions reported as definitely abnormal or normal from 78% to 95% for Observer A and from 72% to 94% for Observer B. Surgical management was changed in 6 patients (19%). Inter-observer variability was reduced with PET/CT.
  
  
  CONCLUSIONS
  PET/CT improves the accuracy of reporting in recurrent colorectal cancer and influences surgical management in a significant proportion of patients when compared to PET only imaging.
authors.affiliation: Department of Colorectal and Laparoscopic Surgery, Chase Farm Hospital, Enfield, USA.
authors.forename: A H
authors.initials: AH
authors.lastname: Engledow
authors.forename: G E L
authors.initials: GE
authors.lastname: Bond-Smith
authors.forename: D
authors.initials: D
authors.lastname: Francis
authors.forename: F
authors.initials: F
authors.lastname: Pakzad
authors.forename: J
authors.initials: J
authors.lastname: Bomanji
authors.forename: A
authors.initials: A
authors.lastname: Groves
authors.forename: P J
authors.initials: PJ
authors.lastname: Ell
keywords: Advanced colorectal cancer; PETCT; Surgical management