Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Centre, Montreal, Canada.Department of Urology, Vita Salute San Raffaele University, Milan, Italy.
Initial treatment options for low-risk clinically localized prostate cancer (PCa) include radical prostatectomy (RP) or observation.
To examine cancer-specific mortality (CSM) after accounting for other-cause mortality (OCM) in PCa patients treated with either RP or observation.
Using the Surveillance Epidemiology and End Results Medicare-linked database, a total of 44 694 patients ≥65 yr with localized (T1/2) PCa were identified (1992-2005).
Intervention: RP and observation.
Propensity-score matching was used to adjust for potential selection biases associated with treatment type. The matched cohort was randomly divided into the development and validation sets. Competing-risks regression models were fitted and a competing-risks nomogram was developed and externally validated.
Overall, 22 244 (49.8%) patients were treated with RP versus 22450 (50.2%) with observation. Propensity score-matched analyses derived 11 669 matched pairs. In the development cohort, the 10-yr CSM rate was 2.8% (2.3-3.5%) for RP versus 5.8% (5.0-6.6%) for observation (absolute risk reduction: 3.0%; relative risk reduction: 0.5%; p< 0.001). In multivariable analyses, the CSM hazard ratio for RP was 0.48 (0.38-0.59) relative to observation (p< 0.001). The competing-risks nomogram discrimination was 73% and 69% for prediction of CSM and OCM, respectively, in external validation. The nature of observational data may have introduced a selection bias.
On average RP reduces the risk of CSM by half in patients aged ≥65 yr, relative to observation. The individualized protective effect of RP relative to observation may be quantified with our nomogram.
Abdollah F, Sun M, Schmitges J, Tian Z, Jeldres C, Briganti A, Shariat SF, Perrotte P, Montorsi F, Karakiewicz PI. Are you the author?
Reference: Eur Urol. 2011 Jun 29. Epub ahead of print.