Heterogeneity of Outcomes in D'Amico Intermediate-Risk Prostate Cancer Patients after Radical Prostatectomy: Influence of Primary and Secondary Gleason Score

Abstract

AIM: The aim of this study was to clarify and examine the outcomes of prostate cancer patients classified as intermediate risk (IR) using the D'Amico risk classification system, specifically focusing on the influence of primary and secondary biopsy Gleason score (BGS). PATIENTS AND METHODS: An institutional review board-approved database of robotic-assisted radical prostatectomies performed after 2006 was stratified by standard D'Amico criteria. IR patients were then sub-stratified by BGS. Pathologic and intermediate-term biochemical disease-free survival (BDFS) outcomes were analyzed. RESULTS: Overall, 1,090 patients were classified as D'Amico low-risk, 896 as IR, and 240 as high-risk. Of the 896 IR patients, 63 had BGS 6, 630 were 3 + 4 = 7, and 203 4 + 3 = 7. Among IR patients, as the BGS increased, there was an increasing likelihood of extracapsular extension (21, 28, and 38%, respectively; p = 0.005), positive surgical margins (14, 26, 31%; p = 0.048), and worse 3-year BDFS (96, 94, 88%; p = 0.01). Multivariable logistic regression and Cox regression analyses confirmed differences among IR groups. CONCLUSION: D'Amico IR patients demonstrate significant heterogeneity in both pathologic outcomes and BDFS. IR patients with a BGS of 6 appear to have similar intermediate-term BDFS as low-risk patients. An increasing BGS from 3 + 3 to 3 + 4 to 4 + 3 results in a higher likelihood of locally-advanced disease and intermediate-term biochemical failure.