Lethal Prostate Cancer in the PLCO Cancer Screening Trial

The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial randomized men to usual care or annual prostate-specific antigen (PSA) screening for 6 yr and digital rectal examination for 4 yr. This trial found no difference between the intervention and usual care arms of the study in the primary end point of prostate cancer (PCa)-specific mortality. The PLCO trial results have had a major impact on health policy and the rate of PSA screening in the United States. We analyzed the 13-yr screening and outcomes data from the 151 participants who died of PCa in the screening arm of the trial to better understand how randomization to screening failed to prevent PCa death in these men. We found that of these men, 81 (53.6%) either were never screened as part of the trial or had an initial positive screen. Only 17 (11.3%) of those who died reached year 6 of the trial with a PSA <4.0 ng/ml. The men who died in the screening arm were also older at study entry than the average PLCO participant (66 vs 62 yr; p < 0.001). Our analysis should inform the interpretation of the PLCO trial and provide insight into future trial design.