BACKGROUND: The objective of the current study was to evaluate the impact of socioeconomic disparities on prostate cancer presentation, treatment, and prognosis in Geneva, Switzerland, in which healthcare costs, medical coverage, and life expectancy are considered to be among the highest in the world. METHODS: This population-based study included all patients diagnosed with invasive prostate cancer among the resident population between 1995 and 2005. Patients were divided into 3 socioeconomic groups according to their last known occupation. Compared were patient and tumor characteristics and treatment patterns between socioeconomic groups. Cox multivariate regression analysis was used to assess and explain socioeconomic inequalities in prostate cancer-specific mortality. RESULTS: Compared with patients of high socioeconomic class, those of low socioeconomic class were more often foreigners, were found less frequently to have screen-detected cancer, were found to have a more advanced stage of disease at diagnosis, and less often had information regarding disease characteristics and staging. These patients underwent prostatectomy less frequently and were more often managed with watchful waiting. The risk of dying as a result of prostate cancer (hazards ratio [HR]) in patients of a low versus high socioeconomic status was increased 2-fold (95% confidence interval [95% CI], 1.5-2.6). After adjustment for patient and tumor characteristics and treatment, the mortality risk was no longer found to be significantly increased (HR, 1.2; 95% CI, 0.8-1.6). CONCLUSIONS: In the current study, patients of low socioeconomic class were found to be at increased risk of dying as a result of their prostate cancer. This increased mortality is largely attributable to delayed diagnosis, poor diagnostic workup, and less invasive treatments in these individuals.