title: PET/CT may change diagnosis and treatment in cancer patients.
abstract: BACKGROUND
  The national focus on cancer has propelled the use of PET/CT for cancer imaging in Denmark. We believe that first-year experiences from a large PET centre may be of interest to new users.
  
  
  METHODS
  Data from all scans made in the period from February 28 2006 to March 1 2007 with a single PET/CT scanner and 18F-fluoro-deoxyglucose (FDG) were collected prospectively along with information on action diagnosis, study purpose, etc. Referring departments indicated if PET/CT had changed or confirmed diagnosis, staging and treatment plan.
  
  
  RESULTS
  A total of 970 scans were made in 826 patients, 14% had 2-5 scans performed. Diagnostic CT was performed in 53%. In all, 792 referrals came from Odense University Hospital. Nearly 85% were from the specialities of oncology (31%), haematology (24%), surgery (14%), internal medicine (9%) and gynaecology (6%). PET/CT for primary diagnosis was mainly used in lung cancer and in cases with unknown primary tumour. In malignant lymphomas and colorectal cancer, the technique was mainly employed for response evaluation. Use of PET/CT for staging and recurrence was more evenly distributed across specialities. PET/CT changed the primary diagnosis in 16% and induced a change in staging and treatment plan in 28% to 32% of cases, respectively.
  
  
  CONCLUSIONS
  FDG PET/CT was mainly used for diagnosis in lung cancer and in cases with an unknown primary tumour, and for response evaluation in lymphomas and colorectal cancer. PET/CT caused a change of staging and treatment plan in 25-33% of cases.
authors.affiliation: Odense University Hospital, Department of Nuclear Medicine, Denmark. hp@dadlnet.dk
authors.forename: Henrik
authors.initials: H
authors.lastname: Petersen
authors.forename: Mie Jung
authors.initials: MJ
authors.lastname: Nielsen
authors.forename: Mette
authors.initials: M
authors.lastname: Høilund-Carlsen
authors.forename: Oke
authors.initials: O
authors.lastname: Gerke
authors.forename: Werner
authors.initials: W
authors.lastname: Vach
authors.forename: Poul Flemming
authors.initials: PF
authors.lastname: Høilund-Carlsen
mesh_terms: D003718:Denmark; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D009369:Neoplasms / Q000175:diagnosis*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed; D051598:Whole Body Imaging
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18