At what age should Prostate-Specific Antigen (PSA) screening start?

PSA Screening Age Recommendations

PSA screening should begin at age 50 for average-risk men, at age 45 for high-risk men (African Americans and those with a family history), and at age 40 for very high-risk men (those with multiple first-degree relatives diagnosed before age 65). 1

Risk-Stratified Screening Initiation

The recommended age to begin PSA screening varies based on risk factors:

1. Average-risk men:

   • Begin at age 50 2, 1
   • Should have at least 10-15 years life expectancy 1

2. High-risk men:

   • Begin at age 45 2, 1
   • Includes:
     • African American men
     • Men with a first-degree relative diagnosed with prostate cancer before age 65

3. Very high-risk men:

   • Begin at age 40 2, 1
   • Includes men with multiple first-degree relatives diagnosed with prostate cancer before age 65

Screening Intervals Based on Initial PSA

After initial PSA testing, the screening interval should be determined by the baseline PSA value:

• PSA < 1.0 ng/mL: Rescreen at age 45 1
• PSA 1.0-2.5 ng/mL: Rescreen every 2 years 1
• PSA ≥ 2.5 ng/mL: Screen annually 1

Important Considerations

• Baseline PSA testing at age 40 can help with risk stratification for future screening 1, 3
• Men with PSA levels in the top 10% for their age group (approximately ≥1.5 ng/mL before age 50) are at particularly high risk and should receive more intensive monitoring 3
• PSA screening should only be offered after thorough informed decision-making, as it involves weighing potential benefits against harms 1, 4

Screening Limitations and Cautions

• PSA screening is not recommended for men over age 70 or those with less than 10-15 years life expectancy 1, 4
• The USPSTF gives a "C" recommendation for men aged 55-69, indicating that the decision should be individualized 1, 4
• While screening may reduce prostate cancer mortality by approximately 1.3 deaths per 1000 men screened over 13 years, this must be balanced against potential harms 4

Potential Pitfalls

• Avoid PSA testing within 2 days of ejaculation or vigorous exercise, as these may cause false elevations 1
• A single elevated PSA should not prompt immediate biopsy and should be verified by a second test 1
• Certain medications like finasteride and dutasteride can lower PSA levels, potentially masking elevated values 1
• PSA is not specific for prostate cancer, which can lead to unnecessary biopsies and overdiagnosis 5, 6

By following these risk-stratified recommendations for when to begin PSA screening, clinicians can help balance the potential mortality benefit against the risks of overdiagnosis and overtreatment.