title: Diffusion tensor imaging of prostate at 3.0 Tesla.
abstract: BACKGROUND
  The feasibility of diffusion tensor imaging (DTI) of prostate has been confirmed by several studies. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values of prostate with healthy or pathological changes remain controversial.
  
  
  OBJECTIVE
  To investigate the efficacy of DTI at 3.0 T in diagnosing prostate cancer in the peripheral zone and to determine the normative ADC and FA values of the normal prostate.
  
  
  METHODS
  T2-weighted imaging (T2WI) and DTI of the prostate was performed in 33 cases with diagnosis confirmed by biopsy at 3.0 T MR. ADC and FA values of cancerous and non-cancerous sextants were compared. Receiver-operating characteristic (ROC) curves were used to compare the ability of ADC, FA and the two values combined in diagnosing prostate cancer in the peripheral zone. DTI data of 20 healthy young volunteers were also acquired. ADC and FA values of the normal central gland and the peripheral zone were compared.
  
  
  RESULTS
  ADC value (1.10 ± 0.09 × 10(-3) mm(2)/s) was lower while FA value (0.37 ± 0.05) was higher in normal central gland, compared with that in normal peripheral zone (1.63 ± 0.15 × 10(-3) mm(2)/s, 0.21 ± 0.07, respectively) (P < 0.0001, P < 0.0001, respectively). Sixteen of 33 cases were confirmed to be malignant while 17 of 33 cases were benign. All the 198 sextants were confirmed by biopsy, including 136 non-cancerous sextants and 62 cancerous sextants. There were significant differences between cancerous sextants (1.02 ± 0.16 × 10(-3) mm(2)/s, 0.38 ± 0.09) and non-cancerous sextants (1.22 ± 0.14 × 10(-3) mm(2)/s, 0.31 ± 0.06) for both ADC and FA values (P <0.0001, P <0.0001, respectively). Significant differences were noted between the AUC of DTI and FA alone (0.86 vs. 0.76, P = 0.0009), but no differences between the AUC of DTI and ADC alone (0.86 vs. 0.84, P = 0.1595).
  
  
  CONCLUSIONS
  ADC and FA values of normal prostate may be compatible with the microstructural organization of prostate. Furthermore, DTI may be a potential tool in diagnosing prostate cancer in the peripheral zone.
authors.affiliation: Department of Radiology, Beijing Hospital, China.
authors.forename: Chunmei
authors.initials: C
authors.lastname: Li
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Saying
authors.initials: S
authors.lastname: Li
authors.forename: Xuna
authors.initials: X
authors.lastname: Zhao
authors.forename: Chen
authors.initials: C
authors.lastname: Zhang
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhou
mesh_terms: D000328:Adult; D016880:Anisotropy; D019540:Area Under Curve; D001706:Biopsy; D003937:Diagnosis, Differential; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D012372:ROC Curve