Objective: Screening using a standardized protocol may improve outcomes of patients undergoing treatment for prostate cancer. We compared the 7- year progression-free survival rates after radical retropubic prostatectomy in patients whose prostate cancer was detected through a formal screening program with those of patients referred for treatment by other physicians who did not use a standardized screening/referral protocol.
Methods: A single surgeon (W.J.C.) performed radical retropubic prostatectomy in 3,177 consecutive patients between 1989 and 2003. Of these patients, 464 had cancer detected in a screening study, and 2,713 were referred from outside institutions. We compared the screened and referred cohorts for age at surgery, clinical stage, pathologic stage, Gleason sum, preoperative prostate-specific antigen (PSA) levels, and adjuvant radiation therapy. Kaplan-Meier product limit estimates were used to calculate 7-year progression-free probabilities, and Cox proportional hazards models were used to determine the clinical and pathologic parameters associated with cancer progression in each group.
Results: The overall 7-year progression-free survival rates were 83% for the screened patients compared with 77% for the referred patients (P = 0.002). Preoperative PSA, Gleason sum, clinical stage, pathologic stage, and adjuvant radiotherapy were all significantly associated with cancer progression. There was a significantly higher proportion of referred patients with a preoperative PSA > or =10, Gleason sum > or =7, and nonorgan-confined disease.
Conclusions: Patients with screened-detected prostate cancer have more favorable clinical and pathologic features, and 7-year progression-free survival rates than referred patients. On multivariate analysis, including other clinical variables, screening status was a significant independent predictor of biochemical outcome.