title: Conventional and diffusion-weighted MRI features in diagnosis of metastatic lymphadenopathy in bladder cancer.
abstract: BACKGROUND
  To compare qualitative and quantitative imaging features from conventional and diffusion-weighted (DW) magnetic resonance imaging (MRI) in detection of metastatic pelvic lymph nodes in bladder cancer patients undergoing cystectomy.
  
  
  METHODS
  Thirty-six patients who had undergone cystectomy for bladder cancer with preoperative MRI with DWI sequence prior to surgery were included. Imaging features on conventional and DW-MRI were compared with histopathology at cystectomy.
  
  
  RESULTS
  Nodal features associated with metastatic lymphadenopathy were short axis (AUC = 0.85, p < 0.001; when SA > 5 mm: sensitivity = 88%, specificity = 75%), long axis (AUC = 0.80, p < 0.001; when LA > 6 mm: sensitivity = 88%, specificity = 71%), apparent diffusion coefficient (ADC) on DWI, normalized to muscle (AUC = 0.66, p = 0.113; when nADC < 1.35: sensitivity = 75%, specificity = 68%), and absence of fatty hilum on conventional imaging (AUC = 0.73, p = 0.012; when fatty hilum absent, sensitivity = 75%, specificity = 71%). ADC without normalization was not associated with metastasis (p = 0.303).
  
  
  CONCLUSIONS
  Imaging findings from conventional MRI and DWI achieved reasonable accuracy for detecting metastatic lymph nodes in bladder cancer, although sensitivity was higher than specificity. A short axis greater than 5 mm on conventional MRI had the highest accuracy of any individual finding. When using DWI, normalization of ADC values to muscle ADC may improve diagnostic performance.
authors.affiliation: NYU Langone Medical Center, New York, New York, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Wollin
authors.forename: Fang-Ming
authors.initials: FM
authors.lastname: Deng
authors.forename: William C
authors.initials: WC
authors.lastname: Huang
authors.forename: James S
authors.initials: JS
authors.lastname: Babb
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Rosenkrantz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D002277:Carcinoma / Q000556:secondary* / Q000601:surgery; D015653:Cystectomy; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010388:Pelvis; D012372:ROC Curve; D012189:Retrospective Studies; D001749:Urinary Bladder Neoplasms / Q000473:pathology* / Q000601:surgery