Screening decreases prostate cancer mortality: 11-year follow-up of the 1988 Quebec prospective randomized controlled trial

PURPOSE: This clinical trial is aimed at evaluating the impact of prostate cancer screening on cancer-specific mortality. SUBJECTS AND METHODS: Forty-six thousand four hundred and eighty-six (46,486) men aged 45-80 years registered in the electoral roll of the Quebec city area were randomized in 1988 between screening and no screening. Screening included measurement of serum prostatic specific antigen (PSA) using 3.0 ng/ml as upper limit of normal and digital rectal examination (DRE) at first visit. At follow-up visits, serum PSA only was used. RESULTS: Seventy-four (74) deaths from prostate cancer occurred in the 14,231 unscreened controls while 10 deaths were observed in the screened group of 7,348 men during the first 11 years following randomization. Median follow-up of screened men was 7.93 years. A Cox proportional hazards model of the age at death from prostate cancer shows a 62% reduction (P < 0.002, Fisher's exact test) of cause-specific mortality in the screened men (P = 0.005). These results are in agreement with the continuous decrease of prostate cancer mortality observed in North America.