Biochemical (prostate specific antigen) recurrence probability following radical prostatectomy for clinically localized prostate cancer

Abstract

Purpose: We retrospectively reviewed the clinical followup for a large series of men with clinically localized prostate cancer who underwent radical retropubic prostatectomy to identify clinical and/or pathological indicators of biochemical (prostate specific antigen [PSA]) recurrence. We then used those indicators to develop multivariate models for determination of recurrence probability following radical retropubic prostatectomy.

Materials and methods: From 1982 to 1999, 2,091 consecutive men underwent radical retropubic prostatectomy and pelvic lymphadenectomy for clinically localized adenocarcinoma of the prostate (clinical stage T1c or T2 disease with Gleason score 5 or greater). Actuarial analysis was performed comparing freedom from biochemical recurrence after radical retropubic prostatectomy (PSA 0.2 ng./ml. or greater.) using the Kaplan-Meier method. Event time distributions for the time to recurrence were compared using the log rank statistic or the Cox proportional hazards regression model. The first model was developed using preoperative variables only and the second model using all available variables. Observed and predicted recurrence-free survival curves for different models were compared to select a model for calculation of predicted recurrence-free probabilities and confidence intervals.

Results: With a median followup of 5.9 years (range 1 to 17) 360 men (17%) had biochemical recurrence. Overall actuarial 5, 10 and 15-year biochemical recurrence-free survival rates were 84%, 72% and 61%, respectively. The relative risk of biochemical recurrence following surgery decreased with time, even after adjusted for other perioperative parameters. Variables identified for the preoperative model were biopsy Gleason score, clinical TNM stage and PSA. Variables identified for the postoperative model were prostatectomy Gleason score, PSA and pathological organ confinement status. Nomograms were generated and corrected for the decreasing relative risk of biochemical recurrence over time.

Conclusions: Using 3 preoperative or postoperative parameters, these nomograms can easily be used to determine the 3, 5, 7 and 10-year biochemical recurrence-free survival probabilities among men who undergo radical retropubic prostatectomy for clinically localized prostate cancer in the modern era.