title: Is [F-18]-fluorodeoxyglucose FDG-PET/CT better than ct alone for the preoperative lymph node staging of muscle invasive bladder cancer?
abstract: OBJECTIVE
  To evaluate whether the use of [F-18]-FDG-PET/CT can accurately predict pelvic lymph node metastasis in patients with muscle invasive TCC of the bladder undergoing radical cystectomy.
  
  
  METHODS
  Fifteen patients with muscle invasive bladder cancer had undergone FDG-PET/CT scan from the skull base to the mid-thighs after IV injection of 6.5MBq (Mega-Becquerel)/Kg of FDG. After intravenous hydration IV furosemide was given to overcome the difficulties posed by urinary excretion of 18F-FDG. PET/ CT data were analyzed as PET and CT images studied separately as well as fused PET/ CT images. The imaging findings were correlated with the histopathology of the nodes (gold standard).
  
  
  RESULTS
  CT and FDG-PET had demonstrated positive lymph nodes in 9 & 8 patients respectively. Among the 15 patients 3 had documented metastasis on histopathology. Both CT and PET could detect the nodes in all these 3 patients (100% sensitivity). Nodes were histologically negative amongst 6&5 patients who had node involvement by CT and PET respectively. Therefore, specificity, positive predictive value (PPV) & negative predictive value (NPV) for CT and PET/CT were 50%, 33.3%, 100% and 58.3%, 37.5%, 100% respectively.
  
  
  CONCLUSIONS
  The theoretical advantage of this cutting edge technology for whole body imaging has not been translated into clinical practice as we found minimal advantage of combined FDG-PET/CT over CT alone for nodal staging of muscle invasive bladder cancer. This may be due to substantial overlap between standardized uptake values (SUVs) from active inflammatory processes with those of malignant lesion.
authors.affiliation: Department of Urology, PGIMER, Chandigarh.
authors.forename: Mete
authors.initials: M
authors.lastname: Uttam
authors.affiliation: Department of Urology, PGIMER, Chandigarh.
authors.forename: Nayak
authors.initials: N
authors.lastname: Pravin
authors.affiliation: Department of Nuclear Medicine PGIMER, Chandigarh.
authors.forename: Bhattacharya
authors.initials: B
authors.lastname: Anish
authors.affiliation: Department of Histopathology, PGIMER, Chandigarh.
authors.forename: Kakkar
authors.initials: K
authors.lastname: Nandita
authors.affiliation: Department of Urology, PGIMER, Chandigarh.
authors.forename: Mandal
authors.initials: M
authors.lastname: Arup
mesh_terms: D000328:Adult; D000368:Aged; D002295:Carcinoma, Transitional Cell / Q000000981:diagnostic imaging* / Q000473:pathology*; D015653:Cystectomy / Q000379:methods; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D001749:Urinary Bladder Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18