title: T2* relaxation time in the detection and assessment of aggressiveness of peripheral zone cancer in comparison with diffusion-weighted imaging.
abstract: OBJECTIVE
  To investigate the feasibility of T2* relaxation time for distinguishing benign from malignant regions, as well as tumour aggressiveness, within the peripheral zone (PZ) of the prostate in comparison with diffusion-weighted imaging (DWI).
  
  
  METHODS
  Fifty-eight patients with prostate cancer underwent 3 T magnetic resonance imaging using multi-echo T2* and DWI (maximum b-value, 2000 s/mm(2)). Parametric maps were obtained for apparent diffusion coefficient (ADC) and T2* values. Two radiologists reviewed these maps and measured ADC and T2* values in sextants positive for cancer at biopsy. Data were analysed using mixed-model analysis of variance and receiver operating characteristic curves.
  
  
  RESULTS
  Ninety-three sextants exhibited a Gleason score of 6; 59 exhibited a Gleason score of 7 or 8. The T2* value was significantly lower in cancerous sextants than in the benign PZ (48.69+0.60 versus 74.14+0.56, p<0.001), as well as in cancerous sextants with higher rather than lower Gleason scores (43.18+0.89 versus 52.18+0.55, p<0.001). The T2* value showed significantly greater specificity for differentiating cancerous sextants from benign PZ than ADC (93.1% versus 89.7%, p<0.001), with equal sensitivity (82.8% versus 81%, p>0.05). The T2* value exhibited significantly greater sensitivity and specificity for differentiating sextants with low- and high-grade cancer than ADC (79.6% versus 64.5% and 81.4% versus 72.9%, respectively; p<0.05). The T2* value had a significantly greater area under the receiver operating characteristic curve for differentiating sextants with low- and high-grade cancer than ADC (0.77 versus 0.71, p<0.01).
  
  
  CONCLUSIONS
  Preliminary findings suggest that the T2* relaxation time has increased diagnostic value compared with DWI in prostate PZ cancer assessment.
authors.affiliation: Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
authors.forename: L-M
authors.initials: LM
authors.lastname: Wu
authors.affiliation: Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
authors.forename: B
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
authors.forename: S-T
authors.initials: ST
authors.lastname: Suo
authors.affiliation: Department of Pathology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Radiology, Wayne State University, Detroit, MI 48201, USA.
authors.forename: J
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Radiology, Wayne State University, Detroit, MI 48201, USA.
authors.forename: E M
authors.initials: EM
authors.lastname: Haccke
authors.affiliation: Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
authors.forename: X-X
authors.initials: XX
authors.lastname: Chen
authors.affiliation: Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China. Electronic address: xujianr@yeah.net.
authors.forename: J-R
authors.initials: JR
authors.lastname: Xu
mesh_terms: D000368:Aged; D038524:Diffusion Magnetic Resonance Imaging; D005240:Feasibility Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000473:pathology*; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity