Prostate Cancer: Localized: Surgical Therapy III (MP50): Moderated Poster 50: Sunday, September 12, 2021
MP50-04 DISCORDANCE OF HIGHER BIOPSY VERSUS PROSTATECTOMY CANCER GRADE IS ASSOCIATED WITH WORSENED CANCER-SPECIFIC SURVIVAL
INTRODUCTION AND OBJECTIVE:
Prostate biopsy is the golden standard for the diagnosis of prostate cancer (PCa). The discordance between the PCa Grade Group (GG) on biopsy (Bx) and the PCa GG from the radical prostatectomy (RP) specimen is quite common, with reported rates of 32-73%. RP GG is considered the most accurate pathologic reference for prognosis. In this study, we tested the hypothesis that a higher discordant preoperative Bx GG may be associated with poorer outcomes versus a concordant or lower Bx GG when examining post-RP cancer-specific survival (CSS).
The SEER-18 database was searched for patients diagnosed with prostate adenocarcinoma as the only malignancy from 2010-2015. Patients were included if they were diagnosed by Bx, received RP without pre-surgical radiation, and assigned pathologic grade on both Bx and RP specimen. The PCa GG system was used for analysis. The CSS was evaluated between patients who had a Bx GG>RP GG and Bx GG≤RP GG. Cox regression was used for the survival analysis.
76,936 patients were included in this study. When the preoperative Bx GG was compared to the RP GG, a total of 13,335 (17.3%) patients encountered downgrading from Bx GG to RP GG. A downgrading of one grade occurred in 10076 (75.6%) of these patients and of 2 or more grades occurred in 3259 (24.4%) patients. We examined if a history of higher Bx GG was associated with poorer PCa CSS controlling for RP GG and other covariates (age, race, preop PSA level, and pathologic TNM stages) and found a history of GG downgrading was independently associated with worsened CSS (HR 1.41, 95%CI 1.02-1.95, p=0.04). Figure 1 demonstrates CSS for downgraded vs non-downgraded PCa patients.
A history of higher Bx GG, and hence downgrading at the time of RP, was associated with worsened survival for a given RP GG.
Source of Funding:
None© 2021 by American Urological Association Education and Research, Inc.