title: Does positron emission tomography/computed tomography change management in colorectal cancer?
abstract: BACKGROUND
  Positron emission tomography/computed tomography (PET/CT) is used pre-operatively in patients with metastatic or recurrent colorectal cancer to identify those who have potentially curative disease. However, a recent randomized trial questioned the added benefit of PET/CT over conventional imaging in patients with liver metastases. The aim of this study was to determine the proportion of patients with colorectal cancer in whom PET/CT altered surgical management, in a single tertiary centre.
  
  
  METHODS
  This was a retrospective study of all patients with colorectal cancer who had a PET/CT for colorectal cancer, funded by the Canterbury District Health Board between 2010 and 2014.
  
  
  RESULTS
  Some 111 PET/CT scans were performed on 105 patients. A total of 38% of PET/CT were for patients with known or suspected liver metastases, 23% for suspected local recurrence and 18% for known or suspected lung metastases. Five scans were for post-operative patients with a rising carcinoembryonic antigen and no attributable source on conventional imaging. PET/CT identified additional extrahepatic sites of disease in 19 of 111 (17%) scans in patients deemed to have potentially operable disease. Overall, PET/CT altered surgical management following six of 42 (14%) scans for patients with liver metastases, four of 20 (20%) scans for patients with lung metastases and six of 26 (23%) scans for patients with local recurrence.
  
  
  CONCLUSIONS
  PET/CT remains a useful adjunct to conventional imaging in the pre-operative workup of patients with colorectal cancer.
authors: Department of General Surgery, Christchurch Hospital, Christchurch, New Zealand.
authors: Rachel
authors: R
authors: Falconer
authors: Department of General Surgery, Christchurch Hospital, Christchurch, New Zealand.
authors: Saxon
authors: S
authors: Connor
authors: Department of Diagnostic and Interventional Radiology, Christchurch Hospital, Christchurch, New Zealand.
authors: Adrian
authors: A
authors: Balasingam
authors: Department of Surgery, University of Otago, Christchurch, New Zealand.
authors: Tim
authors: T
authors: Eglinton
mesh_terms: D000066491:Clinical Decision-Making; D003082:Colectomy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging; D018579:Patient Selection; D000072078:Positron Emission Tomography Computed Tomography; D012189:Retrospective Studies; D062606:Tertiary Care Centers
keywords: colorectal cancer; liver metastases; positron emission tomography/computed tomography