title: Development and External Validation of the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer: Comparison with Two Western Risk Calculators in an Asian Cohort.
abstract: OBJECTIVE
  We developed the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer (KPCRC-HG) that predicts the probability of prostate cancer (PC) of Gleason score 7 or higher at the initial prostate biopsy in a Korean cohort (http://acl.snu.ac.kr/PCRC/RISC/). In addition, KPCRC-HG was validated and compared with internet-based Western risk calculators in a validation cohort.
  
  
  METHODS
  Using a logistic regression model, KPCRC-HG was developed based on the data from 602 previously unscreened Korean men who underwent initial prostate biopsies. Using 2,313 cases in a validation cohort, KPCRC-HG was compared with the European Randomized Study of Screening for PC Risk Calculator for high-grade cancer (ERSPCRC-HG) and the Prostate Cancer Prevention Trial Risk Calculator 2.0 for high-grade cancer (PCPTRC-HG). The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC) and calibration plots.
  
  
  RESULTS
  PC was detected in 172 (28.6%) men, 120 (19.9%) of whom had PC of Gleason score 7 or higher. Independent predictors included prostate-specific antigen levels, digital rectal examination findings, transrectal ultrasound findings, and prostate volume. The AUC of the KPCRC-HG (0.84) was higher than that of the PCPTRC-HG (0.79, p<0.001) but not different from that of the ERSPCRC-HG (0.83) on external validation. Calibration plots also revealed better performance of KPCRC-HG and ERSPCRC-HG than that of PCPTRC-HG on external validation. At a cut-off of 5% for KPCRC-HG, 253 of the 2,313 men (11%) would not have been biopsied, and 14 of the 614 PC cases with Gleason score 7 or higher (2%) would not have been diagnosed.
  
  
  CONCLUSIONS
  KPCRC-HG is the first web-based high-grade prostate cancer prediction model in Korea. It had higher predictive accuracy than PCPTRC-HG in a Korean population and showed similar performance with ERSPCRC-HG in a Korean population. This prediction model could help avoid unnecessary biopsy and reduce overdiagnosis and overtreatment in clinical settings.
authors.affiliation: Department of Urology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae Young
authors.identifier: http://orcid.org/0000-0002-6664-6846
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea.
authors.forename: Sungroh
authors.initials: S
authors.lastname: Yoon
authors.affiliation: Department of Statistics, College of Natural Sciences, Sungshin Women's University, Seoul, Republic of Korea.
authors.forename: Man Sik
authors.initials: MS
authors.lastname: Park
authors.affiliation: Department of Urology, Korea University Ansan Hospital, Ansan, Republic of Korea.
authors.forename: Hoon
authors.initials: H
authors.lastname: Choi
authors.affiliation: Department of Urology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae Hyun
authors.initials: JH
authors.lastname: Bae
authors.affiliation: Department of Urology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Du Geon
authors.initials: DG
authors.lastname: Moon
authors.affiliation: Department of Urology, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sung Kyu
authors.initials: SK
authors.lastname: Hong
authors.affiliation: Department of Urology, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sang Eun
authors.initials: SE
authors.lastname: Lee
authors.affiliation: Anesthesia Consultants of Indianapolis, Indiana, United States of America.
authors.forename: Chanwang
authors.initials: C
authors.lastname: Park
authors.affiliation: Department of Urology, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Seok-Soo
authors.initials: SS
authors.lastname: Byun
mesh_terms: D000368:Aged; D019540:Area Under Curve; D044466:Asian People; D001706:Biopsy; D002138:Calibration; D015331:Cohort Studies; D051517:Digital Rectal Examination; D055088:Early Detection of Cancer / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000208:ethnology*; D012044:Regression Analysis; D056910:Republic of Korea; D018570:Risk Assessment
chemical_list: D017430:Prostate-Specific Antigen