title: Low-dose non-enhanced CT versus full-dose contrast-enhanced CT in integrated PET/CT scans for diagnosing ovarian cancer recurrence.
abstract: OBJECTIVE
  To evaluate low-dose non-enhanced CT (ldCT) and full-dose contrast-enhanced CT (ceCT) in integrated 18F-fluorodeoxyglucose (FDG)-PET/CT studies for restaging of ovarian cancer.
  
  
  METHODS
  One hundred and twenty women who had undergone treatment for ovarian cancer underwent a conventional PET/CT scans with ldCT, and then ceCT. Two observers interpreted and decided in consensus on the PET/ldCT and PET/ceCT images by a 3-point scale (N: negative, E: equivocal, P: positive) per patient and lesion site. Final diagnoses were obtained by histopathological examinations, or clinical follow-up for at least 6 months.
  
  
  RESULTS
  Patient-based analysis showed that the sensitivity, specificity, and accuracy of PET/ceCT was 86.9% (40/46), 95.9% (71/74), and 92.5% (111/120), respectively, whereas those of PET/ldCT were 78.3% (36/46), 95.0% (70/74), and 88.3% (106/120), respectively. All sensitivity, specificity, and accuracy significantly differed between two methods (McNemar test, p<0.0005, p=0.023, and p<0.0001, respectively). The scales of detecting 104 recurrent lesion sites were N:14, E:6, P:84 for PET/ceCT, and N:15, E:17, P:72 for PET/ldCT, respectively. Eleven equivocal and one negative regions by PET/ldCT were correctly interpreted as positive by PET/ceCT.
  
  
  CONCLUSIONS
  PET/ceCT is a more accurate imaging modality with higher confidence for assessing ovarian cancer recurrence than PET/ldCT.
authors.affiliation: Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan. kitajima@med.kobe-u.ac.jp
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kitajima
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Ueno
authors.forename: Kayo
authors.initials: K
authors.lastname: Suzuki
authors.forename: Masato
authors.initials: M
authors.lastname: Kita
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Ebina
authors.forename: Hideto
authors.initials: H
authors.lastname: Yamada
authors.forename: Michio
authors.initials: M
authors.lastname: Senda
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Maeda
authors.forename: Kazuro
authors.initials: K
authors.lastname: Sugimura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000517:prevention & control*; D010051:Ovarian Neoplasms / Q000175:diagnosis* / Q000628:therapy*; D049268:Positron-Emission Tomography; D011379:Prognosis; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18