Eighteen-year follow-up of the Goteborg Randomized Population-based Prostate Cancer Screening Trial: effect of sociodemographic variables on participation, prostate cancer incidence and mortality

Objective: This study examined whether previously reported results, indicating that prostate-specific antigen (PSA) screening can reduce prostate cancer (PC) mortality regardless of sociodemographic inequality, could be corroborated in an 18-year follow-up. Materials and methods: In 1994, 20,000 men aged 50-64 years were randomized from the Goteborg population register to PSA screening or control (1:1) (study ID: ISRCTN54449243). Men in the screening group (n = 9950) were invited for biennial PSA testing up to the median age of 69 years. Prostate biopsy was recommended for men with PSA >= 2.5ng/ml. Last follow-up was on 31December 2012. Results: In the screening group, 77% (7647/9950) attended at least once. After 18 years, 1396 men in the screening group and 962 controls had been diagnosed with PC [hazard ratio 1.51, 95% confidence interval (CI) 1.39-1.64]. Cumulative PC mortality was 0.98% (95% CI 0.78-1.22%) in the screening group versus 1.50% (95% CI 1.26-1.79%) in controls, an absolute reduction of 0.52% (95% CI 0.17-0.87%). The rate ratio (RR) for PC death was 0.65 (95% CI 0.49-0.87). To prevent one death from PC, the number needed to invite was 231 and the number needed to diagnose was 10. Systematic PSA screening demonstrated greater benefit in PC mortality for men who started screening at age 55-59 years (RR 0.47, 95% CI 0.29-0.78) and men with low education (RR 0.49, 95% CI 0.31-0.78). Conclusions: These data corroborate previous findings that systematic PSA screening reduces PC mortality and suggest that systematic screening may reduce sociodemographic inequality in PC mortality.