title: Direct comparison of (18)F-FDG PET and PET/CT in patients with colorectal carcinoma.
abstract: The purpose of this study was to compare (18)F-FDG PET and PET/CT in a population of patients with colorectal cancer.
  
  
  METHODS
  PET and PET/CT images from 45 patients (17 women, 28 men; mean age +/- SD, 60.8 +/- 11.1 y) with known colorectal cancer referred for PET from June to November 2001 were retrospectively reviewed. Images were acquired with a PET/CT scanner, and (68)Ge attenuation correction was applied. PET images and fused (68)Ge attenuation-corrected PET and CT images were independently and separately interpreted by a moderately experienced reader unaware of the clinical information. Certainty of lesion characterization was scored on a 5-point scale (0 = definitely benign, 1 = probably benign, 2 = equivocal, 3 = probably malignant, 4 = definitely malignant). Lesion location was scored on a 3-point scale (0 = uncertain, 1 = probable, 2 = definite). The presence or absence of tumor was subsequently assessed using all available clinical, pathologic, and follow-up information. Analysis was provided for lesions detected by both PET and PET/CT.
  
  
  RESULTS
  The frequency of equivocal and probable lesion characterization was reduced by 50% (50 to 25) with PET/CT, in comparison with PET. The frequency of definite lesion characterization was increased by 30% (84 to 109) with PET/CT. The number of definite locations was increased by 25% (92 to 115) with PET/CT. Overall correct staging increased from 78% to 89% with PET/CT on a patient-by-patient analysis.
  
  
  CONCLUSIONS
  PET/CT imaging increases the accuracy and certainty of locating lesions in colorectal cancer. More definitely normal and definitely abnormal lesions (and fewer probable and equivocal lesions) were identified with PET/CT than with PET alone. Staging and restaging accuracy improved from 78% to 89%.
authors: Russell H Morgan Department of Radiology and Radiological Sciences, Johns Hopkins Hospital, Baltimore, Maryland 21287, USA.
authors: Christian
authors: C
authors: Cohade
authors: Medhat
authors: M
authors: Osman
authors: Jeffrey
authors: J
authors: Leal
authors: Richard L
authors: RL
authors: Wahl
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D014055:Tomography, Emission-Computed; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18