Trends in prostate cancer survival in Spain: results from population-based cancer registries

Abstract

Introduction: The aim of this study is to analyse the evolution of the survival of patients diagnosed with prostate cancer during the period 1995-2003.

Material and methods: This is a population survival study of incident cases of prostate cancer in four Spanish areas: Basque Country, Girona, Murcia and Navarra. We calculated the relative survival (RS) at 5 years and its 95% confidence intervals using a cohort analysis and adjusted for age. To assess the trend in survival between the periods (1995-1999 and 2000-2003) a Poisson regression model was used, adjusting for age, region and period, obtaining the relative risk of death.

Results: The number of patients diagnosed during the 1995- 1999 period was 6493 and 8331 in the period 2000-03. The RS at 5 years adjusted for age increased significantly, from 75.3% (95% CI 73.3-77.2) in the period 1995-99 to 85% (95% CI 83.4-86.4) in the period 2000-03.

Conclusion: In Spain the survival of patients with prostate cancer has increased significantly from 1999 to 2003, probably due to the advancement in diagnosis produced by the opportunistic screening of prostate-specific antigen (PSA). Differences in the dissemination and use of the PSA level could explain the observed geographic differences in the increase of survival. It would be necessary to carry out studies to quantify the produced overdiagnosis by screening with PSA in prostate cancer.