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Author Spotlight: Advancing Prostate Cancer Research Through Improved Tissue Sampling and Biobanking
Published on: November 17, 2023
Prostate Specific Antigen and Biopsy Contamination in the Göteborg-1 Randomized, Population-Based, Prostate Cancer
K Stinesen Kollberg1,2, E Holmberg3,4, A Josefsson1,5,6
1Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Purpose:
Even when a screening study has demonstrated a mortality reduction, the degree of pre-testing and contamination is of importance as it can dilute the "true" effect of screening. Our object was to describe the level of pre-testing and contamination in the Göteborg-1 prostate cancer screening trial.
Materials And Methods:
A total of 20,000 men, 50-64 years old, were invited in 1994 and randomized to either a screening group (offered prostate specific antigen testing every 2 years) or to a control group. Follow-up was through December 31, 2014. Outcome measurement was overall testing in the screening group and control group. A positive prostate specific antigen test was defined as a prostate specific antigen ≥3 ng/ml.
Results:
In the study, 4.2% in the screening group and 4.6% men in the control group were tested before study start. During follow-up, 72% in the control group took at least 1 prostate specific antigen test (contamination) compared to 87% of men in the screening group. Of all prostate specific antigens, 24% in the screening group and 39% in the control group were above threshold. In total, 66% of the men underwent prostate biopsy within 12 months from a raised prostate specific antigen in the screening group and 28% in the control group.
Conclusions:
Similar proportions of men were prostate specific antigen-tested in both the screening group and control group, yet only a minority of contamination prostate specific antigens led to biopsy. Also, men in the screening group started screening at a younger age. These could both be explanations for our result that organized screening is more effective in reducing prostate cancer mortality than non-organized testing. When carried out properly and compared to an unscreened population, the effects of organized screening are likely even greater than previously shown in the Göteborg screening trial.
