Evaluation of prostatic specific antigen and digital rectal examination asscreening tests for prostate cancer

BACKGROUND. The 11,811 first visits and 46,751 annual follow-up visits perf ormed since 1988 were analyzed in order to assess the efficacy of serum pro static specific antigen (PSA) and digital rectal examination (DRE) for diag nosis of prostate cancer. METHODS. At first visit, screening included DRE and measurement of PSA usin g 3.0 ng/ml as upper limit of normal, demonstrated as optimal value in the course of the study. Transrectal echography of the prostate (TRUS) was perf ormed only if PSA and/or DRE was abnormal. For elevated PSA, biopsy was per formed only if PSA was above the value predicted from prostatic volume meas ured by TRUS. At follow-up visits, it was decided during the course of the study to use PSA alone. RESULTS. PSA was above 3.0 ng/ml in 16.6% and 15.6% of men at first and fol low-up visits, respectively. Prostate cancer was found in 2.9% of men invit ed for screening at first visit and in only 0.4% of men at follow-up visits for a 7.1-fold decrease at follow-up visits done up to 11 years. PSA alone allowed to find 90.5% and 90.0% of cancers at first and follow-up visits, respectively, compared to 41.1% and 25.0% by DRE alone. In the presence of normal PSA, 344 and 1,919 DREs are needed to find one prostate cancer at fi rst and follow-up visits, respectively. A significant improvement in stage of the disease is found at follow-up (215 cancers) compared to first visits (337 cancers). Comparison made between men invited for screening and those who were not invited but screened showed no significant difference in term s of incidence and prevalence of prostate cancer as well as diagnosis of ca ncer as a function of age or as a function of PSA, DRE, and TRUS data. The cost for finding one case of prostate cancer is estimated at Can $2,420 and Can $7,105 (first and follow-up visits, respectively, when PSA is used as prescreening). CONCLUSIONS. PSA used as prescreening and followed by DRE and TRUS when PSA is abnormal is highly efficient in detecting prostate cancer at a localize d (potentially curable) stage since 99% of the cancers diagnosed were at su ch a localized stage, thus practically eliminating the diagnosis of metasta tic and noncurable prostate cancer. The approach used is highly reliable, s ensitive, efficient, and acceptable by the general population. The detectio n of clinically nonsignificant cancer is an exception. (C) 2000 Wiley-Liss, Inc.