PURPOSE: To evaluate whether annual updating of the Prostate Cancer Prevention Trial Risk Calculator (PCPTRC) would improve institutional validation over static use of the PCPTRC alone.
MATERIALS AND METHODS: Data from five international cohorts, SABOR, Cleveland Clinic, ProtecT, Tyrol, and Durham VA, comprising n = 18,400 biopsies were used to evaluate an institution-specific annual recalibration of the PCPTRC. Using all prior years as a training set and the current year as the test set, the annual recalibrations of the PCPTRC were compared to static use of the PCPTRC in terms of areas underneath the receiver operating characteristic curves (AUC) and Hosmer-Lemeshow goodness-of-fit statistic (H-L).
RESULTS: For predicting high-grade disease, the median AUC (higher is better) of the recalibrated PCPTRC (static PCPTRC) across all test years for the five cohorts were 67.3 (67.5), 65.0 (60.4), 73.4 (73.4), 73.9 (74.1), 69.6 (67.2), respectively, and the median H-L statistics indicated better fit for recalibration compared to the static PCPTRC for Cleveland Clinic, ProtecT and the Durham VA, but not for SABOR and Tyrol. For predicting overall cancer, median AUCs were 63.5 (62.7), 61.0 (57.3), 62.1 (62.5), 66.9 (67.3), and 68.5 (65.5), respectively, and the median H-L statistics indicated better fit for recalibration on all cohorts except for Tyrol.
CONCLUSIONS: A simple to implement method has been provided to tailor the PCPTRC to individual hospitals in order to optimize its accuracy for the patient population at hand.
Strobl AN, Thompson IM, Vickers AJ, Ankerst DP. Are you the author?
Department of Mathematics of the Technical University Munich, Munich, Germany; Department of Urology of the University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA; Memorial Sloan-Kettering Cancer Center, New York City, New York, USA; Department of Urology of the University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA; Department of Epidemiology and Biostatistics of the University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.
Reference: J Urol. 2015 Jan 27. pii: S0022-5347(15)00184-6.