Objectives: To determine the percentage of localized and potentially curable prostate cancers diagnosed at follow-up screening visits compared with the first screening visit.
Methods: Within the context of a prospective screening study performed in randomly chosen men aged between 45 and 80 years, up to 6-year follow-up screening visits have been performed with serum prostate-specific antigen (PSA) measurement and digital rectal examination (DRE) followed by transrectal ultrasonography of the prostate when PSA or DRE is abnormal.
Results: Of the 117 prostate cancers diagnosed at 14,554 annual follow-up visits, only 1 cancer (0.9%) was metastatic compared with 8% (26/322) at 8029 first visits. Moreover, 97% of the cancers detected at follow-up visits could be identified by PSA alone compared with 86% at first visit. The incidence of 0.8% per year during 15 years of screening between the ages of 55 and 70 years would diagnose localized prostate cancer in 12% of the population, a value not too different from the 10% diagnosed with prostate cancer during life-time in the absence of screening.
Conclusions: The present data show that annual screening with PSA diagnoses clinically localized prostate cancer in more than 95% of cases, thus almost completely eliminating the diagnosis of metastatic prostate cancer. Moreover, the number of prostate cancers diagnosed is not significantly increased by screening.