Prostate cancer grade downgrading at time of prostatectomy provides risk‐stratification insight into future tumor behavior after prostatectomy

Abstract

Background: Prostate biopsy (Bx) sampling-based diagnosis of prostate cancer (PCa) has well-described inaccuracy when compared against whole gland analysis upon prostatectomy. Although upgrading of PCa Grade Group (GG) is often described, the occurrence and prognostic implications of downgrading PCa GG at the time of radical prostatectomy (RP) is less understood. Our objective was to evaluate whether downgrading PCa GG at the time of RP was associated with future tumor behavior. Methods:The SEER database was searched from 2010 to 2017 and patients were included if they were assigned pathological grades on both Bx and RP specimen.Patients were stratified into Bx GG > RP GG and Bx GG ≤ RP GG groups, and tumor behavior after treatment was examined. Cox regression was used for the survival analysis.Results: Here, 99,835 patients were included in this study. A total of 18,516 (18.5%) patients encountered downgrading from Bx GG to RP GG. A downgrading of 1 grade occurred in 13,969 (75.4%) of these patients and of 2 or more grades occurred in 4547 (24.6%) patients. A history of higher Bx GG compared with RP GG increased the risk of cancer-specific mortality (CSM) for each given RP GG controlling for age, race, preop prostate-specific antigen level, percentage of positive biopsy cores, and pathologic TNM stages. Specifically, a history of high Bx GG conferred a 45% increased risk of CSM for any given RP GG (hazard ratio = 1.45 95% confidence interval = 1.16-1.82, p < 0.001). Conclusion:A history of higher Bx GG, and hence downgrading at the time of RP, demonstrates some value as a risk-stratification tool for future cancer outcomes after prostatectomy.

External Tertiary-Care-Hospital Validation of the Epidemiological SEER-Based Nomogram Predicting Downgrading in High-Risk Prostate Cancer Patients Treated with Radical Prostatectomy

“…The downgrading rates in our study (51% for any downgrading and 43% for significant downgrading) were in agreement with the rates reported by Wenzel et al (50% for any downgrading and 44% for significant downgrading) [15]. Previously reported downgrading rates in other tertiary-care-based RP cohorts of patients with Gleason grades of 4 ranged from 45% to 61.5% [26][27][28]. However, these rates cannot be directly compared to those in previous downgrading reports, since no other reports focused only on biopsied high-risk prostate cancer patients while also including Gleason grade group 5.…”

The 17-Gene Genomic Prostate Score Assay Is Prognostic for Biochemical Failure in Men With Localized Prostate Cancer After Radiation Therapy at a Community Cancer Center

“…In this study, higher GPS results were associated with greater risk of all relevant outcomes in both univariable and multivariable analyses that included key clinical factors. This confirms the finding in RP cohorts that a genomic assessment of tumor aggressiveness provides additional information beyond traditional clinical factors such as Gleason grade group (which is highly prone to reclassification 32 , 33 , 34 ), PSA (which is variable and affected by medications and other factors 35 , 36 ), or clinical T stage via digital rectal examination (the reproducibility of which has never been established). These results are also consistent with outcomes from the study of the GPS assay in patients post-RT from a Veterans Affairs cohort.…”

The role of PSMA PET/CT to predict upgrading in patients undergoing radical prostatectomy for ISUP grade group 1 prostate cancer

“…16 Despite the increasing trend in the use of AS, contemporary series revealed that almost 22%-33% of all RP surgeries were still performed for GG1 disease at prostate biopsy. 17,18 Therefore, it is of utmost importance to predict the patients who would most likely upgrade and benefit from active treatment in cases with a biopsy GG1 disease.…”

“…In recent years AS was also recommended to highly selected patients with GG 2 disease by the American Society of Clinical Oncology (ASCO) and European Association of Urology (EAU) guidelines 14,15 A Surveillance, Epidemiology, and End Result Program (SEER) analysis revealed that the use of AS increased from 22% in 2004–2005 to 50% in 2014–2015 in cases with GS ≤ 6 and increased from 9% in 2004–2005 to 13% in 2014–2015 for patients with a GS ≥ 7 16 . Despite the increasing trend in the use of AS, contemporary series revealed that almost 22%–33% of all RP surgeries were still performed for GG1 disease at prostate biopsy 17,18 . Therefore, it is of utmost importance to predict the patients who would most likely upgrade and benefit from active treatment in cases with a biopsy GG1 disease.…”