Prostate-specific antigen and long-term prediction of prostate cancer incidence and mortality in the general population

Background

It is largely unknown whether prostate-specific antigen (PSA) level at first date of testing predicts long-term risk of prostate cancer (PCa) incidence and mortality in the general population.

Objective

Determine whether baseline PSA levels predict long-term risk of PCa incidence and mortality.

Design, setting, and participants

We examined 4383 men aged 20–94 yr from the Danish general population in the prospective Copenhagen City Heart Study. PSA was measured in plasma samples obtained in 1981–1983.

Measurements

PCa incidence and mortality as a function of baseline PSA was assessed using Kaplan-Meier plots of cumulative incidence and competing risk subhazard ratios.

Results and limitations

During 28 yr of follow-up, 170 men developed PCa, and 94 men died from PCa. Median follow-up was 18 yr (range: 0.5–28 yr). For PCa incidence, the subhazard ratio was 3.0 (95% confidence interval [CI], 1.9–4.6) for a PSA level of 1.01–2.00 ng/ml, 6.8 (95% CI, 4.2–11) for PSA 2.01–3.00 ng/ml, 6.6 (95% CI, 3.4–13) for PSA 3.01–4.00 ng/ml, 16 (95% CI, 10.4–25) for PSA 4.01–10.00 ng/ml, and 57 (95% CI, 32–104) for PSA >10.00 ng/ml versus 0.01–1.00 ng/ml. For PCa mortality, corresponding subhazard ratios were 2.2 (95% CI, 1.3–3.9), 5.1 (95% CI, 2.8–9.0), 4.2 (95% CI, 1.8–10), 7.0 (95% CI, 3.8–14), and 14 (95% CI, 6.0–32). For men with PSA levels of 0.01–1.00 ng/ml, the absolute 10-yr risk of PCa was 0.6% for ages <45 yr, 0.7% for ages 45–49 yr, 1.1% for ages 50–54 yr, 1.2% for ages 55–59 yr, 1.3% for ages 60–64 yr, 1.1% for ages 65–69 yr, 1.3% for ages 70–74 yr, and 1.5% for ages ≥75 yr; corresponding values for PSA levels >10.00 ng/ml were 35%, 41%, 63%, 71%, 77%, 69%, 75%, and 88%, respectively.

Conclusions

Stepwise increases in PSA at first date of testing predicted a 3–57-fold increased risk of PCa, a 2–16-fold increased risk of PCa mortality, and a 35–88% absolute 10-yr risk of PCa in men with PSA levels >10.00 ng/ml. Equally important, the absolute 10-yr risk of PCa in men with PSA levels 0.01–1.00 ng/ml was only 0.6–1.5%.