Current prostate cancer (PCa) risk stratification tools perform reasonably well in predicting PCa death, but certain tools are more discriminating than others, according to results from a new study.
Using the nationwide PCa data Base Sweden (PCBaSe) 4.0, Renata Zelic, MD, MSc, PhD candidate, of Karolinska Institutet in Stockholm, Sweden, and colleagues performed a head-to-head comparison of 9 frequently used pretreatment risk stratification tools: the D’Amico, National Institute for Health and Care Excellence (NICE), European Association of Urology (EAU), Genito-Urinary Radiation Oncologists of Canada (GUROC), American Urological Association (AUA), National Comprehensive Cancer Network (NCCN), and Cambridge Prognostic Groups (CPG) risk group systems; the Cancer of the Prostate Risk Assessment (CAPRA) score; and the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram.
Of 139,515 Swedish men diagnosed with nonmetastatic PCa during 1998 to 2016, 15,961 (11%) died from their cancer. The concordance-index at 10 years ranged from 0.73 to 0.81 across the tools and generally increased with the granularity of the risk stratification tool, according to results published in European Urology. The top predictors of PCa death included the MSKCC nomogram (C-index: 0.81), CAPRA score (C-index: 0.80), and CPG system (C-index: 0.78).
“Most tools used clinically and in guidelines are refined versions of the D’Amico system,” Dr Zelic’s team stated. “Our data show that the D’Amico and D’Amico-derived tools are inferior to the MSKCC, CAPRA, and CPG tools.”
“Current risk stratification tools are good and will get better, but the best—we are not there yet,” Annika Herlemann, MD, of the University of California, San Francisco, commented in an accompanying editorial.
“With the growing number of additional risk parameters, such as multiparametric prostate magnetic resonance imaging with fusion-targeted biopsy, and genomic classifiers, existing tools may be refined and new risk stratification tools will likely be introduced to help overcome these limitations,” Dr Herlemann wrote. “Moreover, let us not forget about the readily available data points such as PSA density, or extent and histologic subtypes of Gleason pattern 4.”
Limitations of the study include the relatively short follow up period (median 5.8 years) and the homogenous population (Swedish men). In addition, only a third of men had complete information on all variables used. Missing values were imputed, including clinical T2/T3 substages.
Zelic R, Garmo H, Zugna D, et al. Predicting prostate cancer death with different pretreatment risk stratification tools: A head-to-head comparison in a nationwide cohort study. Eur Urol. 2020;77:180-188. doi: 10.1016/j.eururo.2019.09.027
Herlemann A. Pretreatment risk stratification tools for prostate cancer—Moving from good to better, toward the best. Eur Urol. 2020 77:189-190. doi: 10.1016/j.eururo.2019.10.016