Declining Rates of Extracapsular Extension After Radical Prostatectomy: Evidence for Continued Stage Migration

Abstract

PURPOSE: Prostate-specific antigen (PSA)-based screening is responsible for a profound clinical stage migration in newly detected prostate cancers. Extracapsular extension (ECE) is an important predictor of outcome after radical prostatectomy (RP). We examined trends in the rate of ECE for cancers detected by PSA screening in 731 RP specimens between 1987 and 1997, when screening became routine urologic practice in the United States. METHODS: The rates of ECE were examined in 311 prostates with nonpalpable (stage T1c) disease and 420 with palpable but clinically localized (stage T2) disease. Specimens were step-sectioned and examined by a senior pathologist. Rates of ECE were compared with respect to time, and logistic regression was used to identify predictors of ECE. RESULTS: The rate of ECE decreased from 81% to 36% during the 10-year observation period. Multivariateanalysis involving clinical tumor stage, preoperative serum PSA level, and Gleason score demonstrated that year of treatment was an independent predictor of ECE, with a two-fold reduction of risk occurring during the study period (P < .001; odds ratio, 1.96; 95% confidence interval, 1.37 to 2.78). CONCLUSION: PSA screening has resulted in a downward trend in pathologic stage in clinically localized prostate cancer, independent of preoperative PSA level, tumor stage, and Gleason score. This time-dependent downward stage migration suggests the need for continuous updating of predictive nomograms and caution in interpreting differences in contemporarily treated patients compared with historical controls. Further study is needed to determine whether this trend will translate into improved disease-free survival.