title: Apparent diffusion coefficient as a prognostic biomarker of upper urinary tract cancer: a preliminary report.
abstract: OBJECTIVE
  To investigate the role of apparent diffusion coefficient (ADC) as a biomarker reflecting the aggressiveness of upper urinary tract urothelial cell carcinoma (UUT-UCC).
  
  
  METHODS
  Thirty-four consecutive patients treated with nephroureterectomy for non-metastatic disease were prospectively enrolled in this study. ADC was compared with clinicopathological variables including Ki-67 labelling index (LI) and cancer-specific survival (CSS).
  
  
  RESULTS
  The overall 3-year CSS rate was 82 % (median follow-up, 36 months). ADC was significantly lower in grade 3 disease than in grades 1-2 disease (P = 0.011) and significantly and inversely correlated with Ki-67 LI (ρ = -0.59, P = 0.0002). Low ADCs (<1.10 × 10(-3) mm(2)/s) were significantly associated with shorter CSS (P = 0.039). Multivariate analysis of preoperative variables identified ADC and MRI-based clinical T stage as independent indicators of shorter CSS; the patients were stratified into high-risk (8 patients with low ADC and at least clinical T3) and low-risk (26 patients with high ADC or not more than clinical T2) groups with 3-year CSS rates of 43 % and 93 % (P = 0.0003).
  
  
  CONCLUSIONS
  Our preliminary data suggest the potential role of ADC as a quantitative biomarker reflecting the aggressiveness of UUT-UCC. ADC might be useful for preoperative risk stratification of UUT-UCC patients.
  
  
  CONCLUSIONS
  • Diffusion-weighted MRI offers new information about the aggressiveness of urinary tract cancers. • The apparent diffusion coefficient acts as a quantitative biomarker for upper urinary tract cancers. • ADC inversely correlates with immunohistochemical and histological grading of UUT-UCC. • ADC offers a prognosis for UUT-UCC patients treated with nephroureterectomy.
authors.affiliation: Department of Urology, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-Ku, Tokyo, 113-8519, Japan.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Yoshida
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Koga
authors.forename: Junichiro
authors.initials: J
authors.lastname: Ishioka
authors.forename: Chikako
authors.initials: C
authors.lastname: Ishii
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Nakanishi
authors.forename: Yoh
authors.initials: Y
authors.lastname: Matsuoka
authors.forename: Noboru
authors.initials: N
authors.lastname: Numao
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Saito
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Masuda
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Fujii
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kihara
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D004058:Diffusion; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009362:Neoplasm Metastasis; D011446:Prospective Studies; D011859:Radiography; D012306:Risk; D013997:Time Factors; D014571:Urologic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D019459:Urothelium / Q000473:pathology*
chemical_list: D015415:Biomarkers; D019394:Ki-67 Antigen