title: Non-Gaussian water diffusion kurtosis imaging of prostate cancer.
abstract: OBJECTIVE
  To evaluate the non-Gaussian water diffusion properties of prostate cancer (PCa) and determine the diagnostic performance of diffusion kurtosis (DK) imaging for distinguishing PCa from benign tissues within the peripheral zone (PZ), and assessing tumor lesions with different Gleason scores.
  
  
  METHODS
  Nineteen patients who underwent diffusion weighted (DW) magnetic resonance imaging using multiple b-values and were pathologically confirmed with PCa were enrolled in this study. Apparent diffusion coefficient (ADC) was derived using a monoexponential model, while diffusion coefficient (D) and kurtosis (K) were determined using a DK model. Differences between the ADC, D and K values of benign PZ and PCa, as well as those of tumor lesions with Gleason scores of 6, 7 and ≥8 were assessed. Correlations between parameters D and K in PCa were analyzed using Pearson's correlation coefficient. ADC, D and K values were correlated with Gleason scores of 6, 7 and ≥8, respectively.
  
  
  RESULTS
  ADC and D values were significantly (p<0.001) lower in PCa (0.79±0.14μm(2)/ms and 1.56±0.23μm(2)/ms, respectively) compared to benign PZ (1.23±0.19μm(2)/ms and 2.54±0.24μm(2)/ms, respectively). K values were significantly (p<0.001) greater in PCa (0.96±0.20) compared to benign PZ (0.59±0.08). D and K showed fewer overlapping values between benign PZ and PCa compared to ADC. There was a strong negative correlation between D and K values in PCa (Pearson correlation coefficient r=-0.729; p<0.001). ADC and K values differed significantly in tumor lesions with Gleason scores of 6, 7 and ≥8 (p<0.001 and p=0.001, respectively), although no significant difference was detected for D values (p=0.325). Significant correlations were found between the ADC value and Gleason score (r=-0.828; p<0.001), as well as the K value and Gleason score (r=0.729; p<0.001).
  
  
  CONCLUSIONS
  DK model may add value in PCa detection and diagnosis. K potentially offers a new metric for assessment of PCa.
authors.affiliation: Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
authors.forename: Shiteng
authors.initials: S
authors.lastname: Suo
authors.affiliation: Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
authors.forename: Xiaoxi
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
authors.forename: Lianming
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
authors.forename: Qiuying
authors.initials: Q
authors.lastname: Yao
authors.affiliation: Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Fan
authors.affiliation: Global Applied Science Laboratory, GE Healthcare, Shanghai 201203, China.
authors.forename: He
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China. Electronic address: xujianrong_renji@163.com.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Xu
mesh_terms: D000369:Aged, 80 and over; D000465:Algorithms; D001834:Body Water / Q000378:metabolism*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016011:Normal Distribution; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Diffusion; Kurtosis; Magnetic resonance imaging; Non-Gaussian; Prostate cancer