title: External validation of the cancer of the prostate risk assessment-s score in koreans undergoing radical prostatectomy.
abstract: OBJECTIVE
  To evaluate the validity of the University of California San Francisco Cancer of the Prostate Risk Assessment-S score (CAPRA-S score), a biochemical indicator of recurrent prostate cancer that uses histopathologic data, in Korean prostate cancer patients.
  
  
  METHODS
  A total of 203 prostate cancer patients who underwent radical prostatectomy between February 1997 and November 2010 were observed for longer than 6 months. The CAPRA-S score of 134 patients for whom records were available for preoperative prostate-specific antigen (PSA), pathologic specimen Gleason score, surgical margin, seminal vesicle invasion, extracapsular extension, and lymph node invasion were calculated. Biochemical recurrence was defined as repetitive measurement of PSA ≥0.2 ng/mL at least 6 months after surgery with at least a 4-week interval. The Cox proportional hazard model and Kaplan-Meier analysis were used for the statistical testing.
  
  
  RESULTS
  The CAPRA-S scores were divided into nine groups. The 5-year disease-free survival rate was reduced as the CAPRA-S score increased compared with the group with a CAPRA-S score of 0-1. The CAPRA-S score in this study was more sensitive to biochemical recurrence than was the CAPRA score conducted at this institution (CAPRA-S concordance index, 0.776; CAPRA concordance index, 0.728).
  
  
  CONCLUSIONS
  The CAPRA-S score is judged to be a useful tool for predicting the disease-free survival rate of Korean prostate cancer patients and is thought to assist in establishing postoperative management.
authors.affiliation: Department of Urology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Ki Taek
authors.initials: KT
authors.lastname: Seong
authors.forename: Ju Hyun
authors.initials: JH
authors.lastname: Lim
authors.forename: Chang Myon
authors.initials: CM
authors.lastname: Park
authors.forename: Han Kwon
authors.initials: HK
authors.lastname: Kim
authors.forename: Jong Yeon
authors.initials: JY
authors.lastname: Park
keywords: Disease-free survival; Prostatectomy; Prostatic neoplasms