Objectives: Randomized controlled trials are currently conducted to assess whether the mortality from prostate cancer is reduced by early detection with the use of prostate-specific antigen (PSA) measurements in serum. To be effective, such a program should be able to reduce the absolute number of men diagnosed with metastatic prostate cancer (for which no cure is available). The aim of the present report is to evaluate whether PSA-based screening reduces the risk of being diagnosed with metastatic prostate cancer.
Methods: A population-based, prospective, randomized, controlled screening trial for prostate cancer started in 1995 (the Göteborg branch of the European Randomized Study of Screening for Prostate Cancer [ERSPC]). Ten thousand, randomly selected men aged 50-66 yr were invited for biennial PSA testing, with 10,000 men serving as passive controls for whom diagnosis of metastatic prostate cancer was monitored by using the Swedish Cancer Registry.
Results: After a follow-up of 10 yr, the risk of being diagnosed with metastatic prostate cancer was reduced by 48.9%-that is, decreasing from 47 cases in the control group to 24 cases in the group randomized to PSA-based screening (p=0.0084). However, the risk of being diagnosed with prostate cancer increased 1.8-fold with PSA-based screening.
Conclusions: Biennial PSA screening reduces the risk of being diagnosed with metastatic prostate cancer, the first prerequisite for achieving decreased cancer mortality in younger men. This putative benefit is balanced by a 1.8-fold increased risk for diagnosis of prostate cancer.