title: A prostate biopsy strategy based on a new clinical nomogram reduces the number of biopsy cores required in high-risk patients.
abstract: BACKGROUND
  The nomograms used for prostate cancer risk assessment in Western countries are not directly applicable to Chinese males; consequently, we have developed a new model to evaluate the risk of them developing this disease.
  
  
  METHODS
  A total of 1104 patients who had undergone trans-rectal ultrasound (TRUS)-guided 12 + 1-core prostate biopsy were retrospectively evaluated in the first stage of the study. Age, prostate-specific antigen (PSA), the free/total PSA ratio (f/t), digital rectal examination (DRE) findings, the presence of a hypoechoic mass revealed using ultrasound, ultrasonic detection of microcalcifications, prostate volume (PV) and PSA density were considered as predictive factors. Multiple logistic regression analysis involving a backward elimination selection procedure was used to select independent predictors. We compared positive rates regarding 6-core and 12-core biopsy schemes at different risk levels. In the second stage of the study, 238 cases were evaluated using our nomogram. In higher risk patients, we employed a 6 + 1 core biopsy. Positive rates in the first and second stages of the study were compared.
  
  
  RESULTS
  Age, the baseline median natural logarithm of PSA (Ln[PSA]), Ln(PV), f/t, rate of abnormal DRE findings and rate of hypoechoic masses detected using TRUS were the factors that were finally submitted into our nomogram. A significantly greater area under the receiver-operating characteristic curve was obtained for the nomogram than for PSA level alone (0.853 vs. 0.761). A cancer probability cutoff value of 0.5 suggested no significant difference between the 6-core and 12-core biopsy schemes at higher risk levels. In the second stage of the study we verified that in patients with a cancer probability cutoff value >0.5, a 6 + 1-core biopsy could be used without a reduction in the positive detection rate, and significantly reducing the number of biopsy cores required.
  
  
  CONCLUSIONS
  A nomogram based on data from Chinese males was developed to predict the positive detection rate, ratio of positive cores and Gleason score at each risk level. According to this nomogram, a reasonable biopsy strategy could be constituted to reduce the number of biopsy cores required in subjects at high risk.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Huang
authors.forename: Gong
authors.initials: G
authors.lastname: Cheng
authors.forename: Bianjiang
authors.initials: B
authors.lastname: Liu
authors.forename: Pengfei
authors.initials: P
authors.lastname: Shao
authors.forename: Chao
authors.initials: C
authors.lastname: Qin
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Rd, Nanjing 210029, China. drlxhua@gmail.com.
authors.forename: Lixin
authors.initials: L
authors.lastname: Hua
authors.forename: Changjun
authors.initials: C
authors.lastname: Yin
mesh_terms: D000368:Aged; D000465:Algorithms; D062005:Biopsy, Large-Core Needle / Q000379:methods* / Q000706:statistics & numerical data*; D003936:Diagnosis, Computer-Assisted / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D049451:Nomograms; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000473:pathology*; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity