title: Targeted biopsy based on ADC map in the detection and localization of prostate cancer: a feasibility study.
abstract: OBJECTIVE
  To investigate the feasibility of targeted biopsy based on an apparent diffusion coefficient (ADC) map in the detection and localization of prostate cancer.
  
  
  METHODS
  This study included 288 consecutive patients with high or increasing serum prostate-specific antigen (PSA) levels who underwent prostatic magnetic resonance imaging (MRI) examination with an ADC map. Four core-targeted biopsies of low ADC lesions were performed under transrectal-ultrasound guidance with reference to ADC map. The positive predictive values (PPVs) of low ADC lesions were calculated and compared for the peripheral zone (PZ), transition zone (TZ), and anterior portion, respectively. Comparisons of ADC values and sizes between malignant and nonmalignant lesions were also performed.
  
  
  RESULTS
  A total of 313 low ADC lesions were detected in 195 patients and sampled by targeted biopsies. The PPVs were 55.3% (95% confidence interval [CI]: 50-61) in total, 61.0% (95% CI: 53-69) for PZ, 50.6% (95% CI: 43-58) for TZ, and 90.9% (95% CI: 81-100) for the anterior portion. The most common nonmalignant pathology of low ADC lesions was hyperplasia, followed by chronic prostatitis. There were significant differences in ADC values and sizes between malignant and nonmalignant low ADC lesions.
  
  
  CONCLUSIONS
  Targeted biopsies could be capable of detecting cancers well wherever they may be in the prostate, although the PPVs varied depending on the location of low ADC lesions.
authors.affiliation: Department of Radiology, Kurashiki Central Hospital, Kurashiki, Japan. yw5904@kchnet.or.jp
authors.forename: Yuji
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Masako
authors.initials: M
authors.lastname: Nagayama
authors.forename: Tohru
authors.initials: T
authors.lastname: Araki
authors.forename: Akito
authors.initials: A
authors.lastname: Terai
authors.forename: Akira
authors.initials: A
authors.lastname: Okumura
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Amoh
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ishimori
authors.forename: Satoru
authors.initials: S
authors.lastname: Nakashita
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Dodo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D062005:Biopsy, Large-Core Needle / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D061705:Image-Guided Biopsy / Q000379:methods*; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010363:Pattern Recognition, Automated / Q000379:methods*; D011471:Prostatic Neoplasms / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity