A letter published in the May 5, 2016 issue of the New England Journal of Medicine questions the findings of what has been called a landmark study on the value of prostate specific antigen (PSA) testing to screen for prostate cancer.
Jonathan E. Shoag, MD, and Sameer Mittal, MD, of New York Presbyterian Hospital, and Jim C. Hu, MD, MPH, of Weill Cornell Medical College evaluated methodology employed in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial conducted from 1993 though 2001. The trial's findings, which concluded no significant difference in prostate cancer mortality over a seven year follow-up between men who received usual care and those who were screened with annual PSA testing for six years and digital rectal examination for four years, were the basis of an updated statement by the U.S. Preventive Service Task Force in 2012 that recommended against PSA-based screening for the disease.
According to responses to a follow-up survey administered to a subgroup of patients, the portion of control participants who reported having received at least one PSA test prior to or during the trial approached 90%. "We demonstrate that the PLCO study did not compare a group of men who received PSA screening to a group of men who were not screened, but compared men who were screened to other men who were screened, and we should therefore reconsider any decisions based on the study," Dr Shoag stated.
"We expect this article to have a profound impact on the debate over the value of PSA screening," Dr Hu predicted. "While there are risks of over-diagnosis and over-treatment associated with PSA testing, it can play an important role in preventing prostate cancer deaths as part of a personalized approach to cancer screening. We're going to have to reconsider this issue."