Causes of PSA Elevation
Multiple conditions can cause elevated PSA levels, with the most common being benign prostatic hyperplasia (BPH), prostatitis, and prostate cancer. 1
Common Causes of PSA Elevation
Prostatic Conditions
- Prostate cancer: PSA is elevated in most men with prostate cancer, though the degree of elevation correlates with tumor volume and stage 1
- Benign prostatic hyperplasia (BPH): About 25% of men with BPH have elevated PSA levels 1
- Prostatitis: Both acute and chronic inflammation can significantly raise PSA levels, sometimes to extremely high values 2, 3
Iatrogenic/Procedural Causes
- Prostate biopsy: Causes substantial PSA elevation; testing should be postponed for at least 3-6 weeks after biopsy 1
- Urethral or prostatic trauma: Including traumatic catheterization 1
- Prostate massage: Can increase PSA levels approximately 1.5-2 times 4
- Transurethral resection: Can significantly increase PSA 4
Other Factors Affecting PSA Levels
- Recent ejaculation: May cause variable increases in PSA 1
- Laboratory variability: Can range from 20-25% depending on standardization used 1
Important Considerations When Interpreting PSA
Medication Effects
- 5α-reductase inhibitors (finasteride, dutasteride):
- Typically reduce PSA by approximately 50% within 6-12 months 1, 5
- Effect is highly variable - after 12 months, only 35% of men show the expected 40-60% decrease 1
- For interpretation, PSA values should be doubled for comparison with normal ranges in untreated men 5
- Failure to achieve significant PSA decrease while taking these medications may indicate increased prostate cancer risk 1
Age-Related Factors
- PSA levels naturally increase with age due to increasing prostate volume 1
- Age-specific PSA thresholds may improve cancer detection sensitivity 1
Clinical Pearls and Pitfalls
Important Caveats
- PSA is not cancer-specific: No PSA level definitively indicates cancer 6
- Normal PSA doesn't rule out cancer: Approximately 1 in 7 men with PSA levels below 4.0 ng/mL have prostate cancer 1
- Elevated PSA doesn't confirm cancer: Only about 25% of men with PSA between 4-10 ng/mL have prostate cancer on subsequent biopsy 1
- PSA kinetics matter: The rate of PSA increase over time (PSA velocity) may be more important than absolute values in predicting cancer risk 1
When Evaluating Elevated PSA
- Consider confirming an abnormal PSA before proceeding to biopsy 1
- Use the same PSA assay for longitudinal monitoring as assays are not interchangeable 1
- Empiric antibiotic use has limited value for improving test performance in asymptomatic men with elevated PSA 1
- For men with suspected prostatitis and elevated PSA, antimicrobial treatment may lower PSA to normal range 3
By understanding these various causes of PSA elevation and considering them in clinical context, clinicians can better interpret PSA results and determine appropriate next steps in patient management.