USPSTF recommends informed patient preference to guide PSA screening
EBM Focus - Volume 13, Issue 25
- The United States Preventive Services Task Force (USPSTF) recommendations from 2012 discouraged prostate-specific antigen (PSA) screening for prostate cancer.
- The recommendations have been recently updated due to new evidence and the increased use of active surveillance which may decrease concerns regarding harms associated with unnecessary treatment.
- The 2018 USPSTF update recommends shared decision making for periodic PSA screening after discussion of potential benefits and harms based on family history, race/ethnicity, comorbidities, patient values, and other health needs in men aged 55-69 years. Periodic PSA screening is not recommended for men ≥ 70 years old.
In 2012, the USPSTF recommended against prostate-specific antigen (PSA) screening in all men regardless of age (Ann Intern Med 2012). The recommendations were recently updated in light of the increasing use of active surveillance rather than immediate treatment for low-risk prostate cancer, which may decrease treatment-related harms, and the availability of longer follow-up data suggesting that the benefit of screening to prevent death from prostate cancer increases over time. The supporting evidence for the updated 2018 USPSTF Recommendation Statement was published in a recent systematic review of 63 studies evaluating PSA prostate cancer screening, treatment for localized prostate cancer, and prebiopsy risk calculators in 1,904,950 men. Meta-analyses for outcomes evaluating benefits and harms of PSA screening were not performed due to heterogeneity in the populations and interventions in the included studies. Three randomized trials in the review compared PSA screening vs. no screening in 647,906 asymptomatic men. The median follow-up time ranged from 10 to 14.8 years. The screening intervals in the intervention arm ranged from a single invitation to every 1-4 years, and the PSA thresholds prompting biopsy varied across trials. The age of the men evaluated was 50-69 years, 55-69 years, and 55-74 years in one trial each.
There was no significant difference between groups in all-cause mortality in any of the three trials. Inconsistent results were observed for prostate cancer mortality. PSA screening at 2-4 year intervals was associated with reduced prostate cancer mortality in 1 trial with 162,243 men (0.48% vs. 0.6% with no screening, relative risk [RR] 0.79, 95% CI 0.69-0.91). The number needed to invite (NNI) for PSA screening ranged from 490 to 1,929 over a median follow-up of 13 years. No significant difference in this risk was found in the other 2 trials. Screening every 2 to 4 years was associated with decreased risk of metastatic cancer in a subgroup analysis of 4 centers in 1 trial at a median follow-up of 12 years in 146,322 men (RR 0.7, 95% CI 0.6-0.82, NNI 227-556). False-positive results among screened men ranged from 10.4% to 17.8% in 2 trials, estimates of overdiagnosis of cancer detected by screening ranged from 16.4% to 50.4% in all 3 trials, and overall complication rate ranged from 2% to 5.6% of men undergoing biopsy in 2 studies.
The findings outlined in the systematic review suggest that PSA screening may not reduce all-cause mortality. The evidence for prostate cancer mortality is inconsistent and may reflect the differences in adherence to protocol among the 3 trials. There was high adherence to screening in the 1 trial finding a difference. In the other 2 trials, 1 trial had high crossover from the no-screening arm to the screening arm, and the other had low adherence to the single invitation for a PSA screen. It should be noted that the evidence evaluating screening in men > 70 years old is very limited and the potential harms and benefits should be weighed in light of existing comorbidities. The evidence is also limited among men who are African American or who have a family history of prostate cancer. This is of importance as these groups may be at increased risk of prostate cancer death compared to the general population (SEER Cancer Stat Facts: Prostate Cancer. National Cancer Institute). Further research is needed to evaluate whether these high risk groups would benefit from earlier screening, and whether there is clinical benefit to be derived from the use of prebiopsy risk calculators or other tests in combination with PSA screening. In summary, the decision to undergo PSA screening should balance the potential reduction in prostate cancer mortality with potential harms such as false-positive results, overdiagnosis, and biopsy-related complications in view of the patient’s personal risk profile, comorbidities, and preferences. Decision aids to facilitate these types of discussions with patients are available.
For more information, see the Prostate cancer screening topic in DynaMed Plus. DynaMed users click here. Also see the USPSTF infographic and the Prostate specific antigen (PSA) test - Option Grid in DynaMed Plus.