'Smarter' PSA Testing May Reduce Harms of Testing While Preserving Life-saving Benefits

Using a selective screening strategy for prostate cancer may reduce the harms associated with testing while preserving the number of lives saved.

Measuring blood levels of prostate-specific antigen (PSA) can help doctors determine which patients may be at risk for prostate cancer. Patients with an elevated PSA level may require a biopsy to determine if cancer is present. However, biopsies are associated with many troublesome side effects and still cannot tell a doctor with certainty which cases of prostate cancer are life-threatening and require treatment.

Current prostate cancer screening guidelines have been the source of controversy. While only one guideline recommends against screening altogether, others are less clear, recommending informed decision-making on an individual level.

This can be difficult because there is sparse data available to help doctors have nuanced conversations with their patients about whether and how often to have prostate cancer screening. Researchers used a computer model to compare 35 screening strategies that varied in terms of age of first and last screening, screening intervals, and PSA thresholds for biopsy referral.

The researchers looked at false-positive results, cancer detected, overdiagnoses (cancers detected that would otherwise never become clinically significant), deaths from prostate cancer, lives saved, and months of life saved. They found that compared with a standard screening strategy, using higher thresholds for biopsy referral for older men and screening men with initially low PSA levels less frequently may be a way to improve the tradeoff between screening and overdiagnosis.

The author of an accompanying editorial does not believe this study will do much to quiet the debate on whether to screen for prostate cancer. The author notes the many limitations of the model which does not consider important factors such as race and family history, patient preferences, or potential complication of incontinence or impotence.

As the debate rages on, the author suggests that physicians engage in shared decision-making with patients with regard to prostate cancer screening.