PSA cancer screening: A case for shared decision-making
Whether to screen for prostate cancer using PSA testing is a difficult decision for many men. Here’s the information you need to help them make an educated choice.
PRACTICE RECOMMENDATIONS
› Recommend individualized decision-making to men ages 55 to 69 years after discussing the potential benefits and risks of prostate-specific antigen (PSA)-based screening. B
› Do not use a PSA-based screening method for prostate cancer in men ages < 50 years or > 70 years or men with a life expectancy < 10 years. C
› Do not routinely recommend PSA-based screening to men with a family history of prostate cancer or to men who are African American. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
In the ERSPC 13-year follow-up publication, the authors concluded that a substantial reduction in prostate cancer mortality is attributable to testing with PSA.18 Despite limitations in the study design (eg, France entered after 2 years, screening intervals varied between 2 and 4 years, biopsy indications varied, and screening was discontinued at different times), PSA screening detected more prostate cancer than was detected in the control arm (10.2% vs 6.8%).
In the initial 11 years of follow-up, the study group experienced a 21% reduction in prostate cancer mortality, even though the absolute decrease ranged from only 0.6% (545 per 89,352) to 0.5% (355 per 72,891). The updated absolute risk reduction of death from prostate cancer at 13 years of follow-up showed a larger benefit: 0.11 per 1000 person-years or 1.28 per 1000 men randomized, which is equivalent to 1 prostate cancer death averted per 781 (95% confidence interval [CI], 490-1929) men invited for screening, or 1 per 27 (17-66) additional prostate cancers detected.
The PLCO trial did not show any significant difference in prostate cancer detection (11.1% screened vs 9.9% control), and there was no improvement in prostate cancer mortality (3.7 vs 3.4 death per 10,000 person-years).10 However, the PLCO trial suffered from issues of contamination, which may have influenced the overall results. About 52% of men in the control (usual care) group received a PSA test at some point during the study. And more than two-thirds of the men who had a prostate biopsy because of a positive PSA test did not have prostate cancer.
Community standards for the PSA threshold for biopsy were applied in various centers (> 4 ng/ml in general) in PLCO, whereas in ERSPC, a cut-off PSA value ≥ 3 ng/mL was used for biopsy. Because of the lower PSA threshold, ERSPC may have identified cancers that would have had good outcomes without any intervention.
The harms of PSA screening
While it is unclear whether PSA screening results in any improvement in patient-centered outcomes, it does lead to downstream intervention due to overdiagnosis, which precipitates unnecessary anxiety, biopsies, and overtreatment (eg, excess radiation, overuse of androgen deprivation therapy).19 Biopsies carry the risk of hematuria (22.6%), hematospermia (50.4%), and urinary tract infection.20 Data from SEER-Medicare showed that prostate biopsy was associated with a 2.65-fold increased risk of hospitalization within 30 days of the procedure compared to a control population.21
Continue to: Overdiagnosis leads to overtreatment...
