Radical prostatectomy vs radiotherapy vs observation among older patients with clinically localized prostate cancer: a comparative effectiveness evaluation

Authors


  • MS and J.D.S contributed equally to the work.

Abstract

Objective

  • To compare efficacy between radical prostatectomy (RP), radiotherapy and observation with respect to overall survival (OS) in patients with clinically localized prostate cancer (PCa).

Methods

  • Using data (1988–2005) from the Surveillance, Epidemiology, and End Results–Medicare linked database, 67 087 men with localized PCa were identified.
  • The prevalence of the initial treatment strategy was quantified according to patients' life expectancy ([LE] <10 vs ≥10 years) at initial diagnosis and according to tumour stage. To reduce the unmeasured bias associated with treatment, we performed an instrumental variable analysis.
  • Stratified (by stage and LE) Cox regression and competing-risks regression analyses were generated for the prediction of OS and cancer-specific mortality, respectively.

Results

  • Among patients with <10 years of LE, most were treated with radiotherapy (49%) or observation (47%). Among patients with ≥10 years of LE, most received radiotherapy (49%), followed by RP (26%).
  • In men with <10 years of LE, RP and radiotherapy were not different with respect to OS (hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.45–1.48, P = 0.499). Conversely, in men with ≥10 years of LE, RP was associated with an improved OS compared with observation (HR: 0.59, 95% CI: 0.49–0.71, P < 0.001) and radiotherapy (HR: 0.66, 95% CI: 0.56–0.79, P < 0.001).
  • Similar results were recorded in competing-risks regression analyses.

Conclusion

  • In patients with an estimated LE ≥10 years at initial diagnosis, RP was associated with improved survival compared with radiotherapy and observation, regardless of disease stage.

Ancillary