New prostate cancer screening guidelines clarify benefits, risks

Men ages 55 to 69 who are considering prostate cancer screening should talk with their doctors about the benefits and harms of prostate-specific antigen testing and proceed based on their personal values and preferences, according to a new clinical practice guidelines released recently by the American Urological Association. Dr. Ruth Etzioni of the Public Health Sciences Division served on the panel that developed the guidelines.
 
The highest quality evidence for screening benefit (lower prostate cancer mortality) was in men ages 55 to 69 years screened at two- to four-year intervals; data demonstrated that one man per 1,000 screened prevented a prostate cancer death over a decade. However, over a lifetime, this benefit could be much greater. There are also men outside this target age range who could benefit from screening because they are at a higher risk of prostate cancer due to race, family history, etc. These men should discuss their risk with their physicians and assess the benefits and risks of testing.
 
The guidelines indicate:

• PSA screening in men under age 40 years is not recommended.
  
• Routine screening in men between ages 40 to 54 years at average risk is not recommended.
  
• For men ages 55 to 69 years, the decision to undergo PSA screening involves weighing the benefits of preventing prostate cancer mortality in one man for every 1,000 men screened over a decade against the known potential harms associated with screening and treatment. For this reason, shared decision-making is recommended for men age 55 to 69 years who are considering PSA screening and proceeding based on patients' values and preferences.
  
• To reduce the harms of screening, a routine screening interval of two years or more may be preferred over annual screening in those men who have participated in shared decision-making and decided on screening. As compared to annual screening, it is expected that screening intervals of two years preserve the majority of the benefits and reduce overdiagnosis and false positives.
  
• Routine PSA screening is not recommended in men over age 70 or any man with less than a 10- to 15-year life expectancy.

"I think the guidelines will help men to have a realistic view of the threat that prostate cancer presents to their health and the likelihood that PSA screening will reduce that risk," Etzioni said. "It will help them to determine at what ages and how often to be screened should they decide that the benefits outweigh the risks. Most of all, it will clarify the point that there are potential harms associated with screening that increase as men age, and their decision about whether to be screened should be an informed one based on the available evidence regarding harm and benefit."

The new guidelines are significantly different from AUA's 2009 PSA best-practice statement as they were developed using evidence from a systematic literature review rather than consensus opinion; they provide rating and interpretation of the evidence based on randomized controlled trials with modeled and population data as supporting evidence; and the developed statements that do not go beyond the available evidence. In developing the guidelines, the panel acknowledged that ongoing research (including studies on biomarkers other than PSA) might lead to changes in the guidelines statements. They plan to update the guidelines regularly based on new evidence.

[Adapted from an American Urological Association news release]