title: Forced diuresis improves the diagnostic accuracy of 18F-FDG PET in abdominopelvic malignancies.
abstract: Our aim was to evaluate the role of forced diuresis in improving the diagnostic accuracy of abdominopelvic (18)F-FDG PET.
  
  
  METHODS
  Thirty-two patients were enrolled. Besides the presence of known intravesical tumors or undefined renal lesions on the initial PET scan, the inclusion criterion was the appearance of indeterminate or equivocal (18)F-FDG foci that extended along the course of the urinary tract and could not confidently be separated from urinary activity. For each patient, a second abdominopelvic PET study was performed after intravenous injection of 0.5 mg of furosemide per kilogram of body weight (maximum, 40 mg) coupled with parenteral infusion of physiologic saline.
  
  
  RESULTS
  Forced diuresis coupled with parenteral hydration eliminated any significant (18)F-FDG activity from the lower urinary tract in 31 (97%) of 32 patients after the bladder had been voided 3 successive times. Twelve intravesical lesions were visualized with outstanding clarity, whereas radiologic suspicion of locally recurrent bladder tumors was ruled out in 3 patients. Among 14 indeterminate or equivocal extravesical foci, 7 were deemed of no clinical value because they disappeared after furosemide challenge, whereas 7 persisting foci were proven to be true-positive PET findings. The performance of (18)F-FDG PET in characterizing 3 renal-space-occupying lesions could not be improved by our protocol.
  
  
  CONCLUSIONS
  Furosemide challenge has the potential to noninvasively resolve the inherent (18)F-FDG contrast handicap in the lower urinary tract.
authors.affiliation: Department of Nuclear Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. Mohamed-Ehab.Kamel@chuv.ch
authors.forename: Ehab M
authors.initials: EM
authors.lastname: Kamel
authors.forename: Patrice
authors.initials: P
authors.lastname: Jichlinski
authors.forename: John O
authors.initials: JO
authors.lastname: Prior
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Meuwly
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Delaloye
authors.forename: Laurent
authors.initials: L
authors.lastname: Vaucher
authors.forename: Jerome
authors.initials: J
authors.lastname: Malterre
authors.forename: Sandra
authors.initials: S
authors.lastname: Castaldo
authors.forename: Hans-Juerg
authors.initials: HJ
authors.lastname: Leisinger
authors.forename: Angelika Bischof
authors.initials: AB
authors.lastname: Delaloye
mesh_terms: D000328:Adult; D004231:Diuresis; D005260:Female; D019788:Fluorodeoxyglucose F18; D005665:Furosemide / Q000494:pharmacology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods; D010386:Pelvic Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000532:radiotherapy; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods; D001749:Urinary Bladder Neoplasms / Q000188:drug therapy
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005665:Furosemide