Five years ago, a large randomized trial was reported as not showing any effect of PSA screening on prostate cancer mortality. The study, called the PLCO (Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial) was a major factor in the recommendation of the U.S. Preventive Services Task Force’s (USPTSTF) decision to recommend against routine PSA screening in 2012. Contrary to the PLCO study, another large study concluded that there is a survival benefit to PSA screening. Over the years, there has been a lot of controversy about the role of PSA screening.
This week, a new analysis of these studies concludes that both actually show that PSA screening does reduce deaths from the disease. The new analysis showed that the original PLCO study did not properly analyze for differences in the methods and timing of screening (almost 90% of the supposed “control” group actually was screened), and when this was corrected for, the study also showed that mortality was reduced. The new analysis showed a 25 to 31% lower risk in one study, and 27 to 32% lower risk in the second study of patients dying from prostate cancer among men who were screened compared to men who were not screened. Thus both studies showed similar outcomes with improved survival in the patients who were screened.
These two data "have finally put to rest the question of whether PSA screening reduces prostate cancer mortality," writes Andrew J. Vickers PhD, and an accompanying editorial. However, he maintains that the implementation of PSA screening needs to be improved so that overdiagnosis and overtreatment, which may result from an appropriate PSA screening, can be reduced.
My interpretation of the data is that healthy men should obtain at least a baseline PSA level and have subsequent screening tailored to their individual risk. In addition, those men who are screened and have an elevated PSA but otherwise are expected to have a low risk of aggressive disease should discuss their options with their physician. There are new blood tests available which help decide which patients will benefit from a biopsy. Probably most important is careful decision-making about who needs treatment. A careful discussion with your physician about the benefits of waiting and watching the change in PSA versus treatment using either radiation or surgery is most important. The good news is that we now know much more about the value of PSA screening and how to use that information to improve the quality and duration of life for patients.