title: Symmetry based prostate cancer detection.
abstract: OBJECTIVE
  To retrospectively assess the value of left and right half symmetry analysis in prostate T2 weighted images (T2WI) for improving prostate cancer (PCa) screening.
  
  
  METHODS
  T2WI and other data of a total of 66 males were collected; the control group and cancer group had 33 patients each. Thresholding geometric active contours algorithm was used for prostate region segmentation, and the measure of local reflectional symmetry algorithm was applied to extract the longitudinal symmetry axes. After that, cross-correlation coefficients (CCs) of the left and right halves of each prostate were obtained.
  
  
  RESULTS
  Data analysis showed that the mean and variance of the value of the left and right half CCs of prostate T2WI in the cancer group and control group were 0.73 ± 0.05 and 0.82 ± 0.06, respectively. The area under the receiver operating characteristic curve was 0.87, and the specificity and the sensitivity were 91% and 70%, respectively. The p < 0.001 indicated that the value of CCs of the prostates between the two groups was significantly different.
  
  
  CONCLUSIONS
  The symmetry in T2WI is a potential useful index for PCa screening and has a potential value for PCa detection and localizations of tumours for biopsy.
  
  
  CONCLUSIONS
  Texture bilateral symmetry of prostate T2WI is employed to screen the suspected prostate tumour.
authors.affiliation: 1 College of Electronic Engineering, Chengdu University of Information Technology, Chengdu, Sichuan, China.
authors.forename: L
authors.initials: L
authors.lastname: Yang
authors.forename: Y
authors.initials: Y
authors.lastname: Xie
authors.forename: B
authors.initials: B
authors.lastname: Li
authors.forename: M
authors.initials: M
authors.lastname: Xie
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001706:Biopsy; D016022:Case-Control Studies; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity