Digital rectal examination-associated alterations in serum prostate-specific antigen.

Area of Science:

• Urology
• Oncology
• Clinical Chemistry

Background:

• Prostate-specific antigen (PSA) is a key biomarker for prostate cancer screening.
• Digital rectal examination (DRE) is a common component of prostate cancer screening programs.
• The potential impact of DRE on PSA levels requires clarification to ensure accurate screening results.

Purpose of the Study:

• To investigate the effect of digital rectal examination (DRE) on serum prostate-specific antigen (PSA) measurements.
• To determine the clinical significance of PSA level changes following DRE.
• To assess the reliability of PSA testing in the context of prior DRE.

Main Methods:

• A prospective study involving 2,736 ambulatory men undergoing prostate cancer screening.
• Serum PSA levels were measured immediately before and after DRE.
• Nonparametric Wilcoxon signed rank test was used to compare pre- and post-DRE PSA values.
• Analysis of PSA changes in relation to initial PSA levels and patient diagnoses (benign prostatic hyperplasia, prostatitis, prostate cancer).

Main Results:

• A small but statistically significant increase in PSA levels was observed after DRE.
• The magnitude of PSA increase due to DRE was clinically insignificant.
• Patients with higher initial PSA levels or specific conditions (prostatitis, prostate cancer) showed larger increases post-DRE.
• Less than 2% of patients experienced a PSA rise across the 4 micrograms/L threshold, with most remaining below 5 micrograms/L post-DRE.

Conclusions:

• Digital rectal examination (DRE) does not significantly elevate prostate-specific antigen (PSA) levels to a clinically concerning degree.
• Clinicians can be reassured that DRE is unlikely to cause falsely high PSA readings.
• The study supports the continued use of PSA testing in screening programs that include DRE.