Introduction:
High prostate cancer tumor volume is associated with greater biologic aggressiveness and is commonly accepted as prognostic of worse outcomes. Decipher, a 22-marker genomic risk classifier (GC), correlates with worse cancer biology and is included in contemporary guidelines to improve risk stratification. We characterized the relationship between tumor volume (measured by percent positive cores, PPC) and cancer biology (measured by GC) in men who underwent prostate biopsy in a population-based tumor registry.
Methods:
Prostate biopsies from 52,272 men profiled with Decipher captured in a population-based prospective tumor registry collected from 2016 to 2021. The significance of differences in distribution across grade group (GG) strata was assessed via the Mann-Whitney U-test, and the correlation of PPC with GC score across GG strata was examined using the Pearson correlation coefficient and multivariable linear regression controlled for clinicopathologic characteristics.
Results:
A total of 38,921 (74%) biopsies passed quality control (14,331 GG1; 16,159 GG2; 5,661 GG3; 1,775 GG4; and 995 GG5). Median PPC and GC increased with sequentially higher GG. There was an increasingly positive correlation (r) between PPC and GC in GG2-5 prostate cancer (r [95% CI] 0.07 [0.5, 0.8] in GG2, 0.15 [0.12, 0.17] in GG3, 0.20 [0.15, 0.24] in GG4, and 0.25 [0.19, 0.31] in GG5), with no correlation in GG1 disease (r=0.01 [-0.001,0.03]). In multivariable linear regression, GC was significantly associated with higher PPC for GG2-5 (all p<0.05) but was not significantly associated with PPC for GG1. Limitations include retrospective design and lack of final pathology from radical prostatectomy specimens.
Conclusion:
Higher tumor volume was associated with worse GC for GG2-5 prostate cancer, whereas tumor volume was not associated with worse GC for GG1 disease. The finding that tumor volume is not associated with worse cancer biology in GG1 disease encourages active surveillance for most patients irrespective of tumor volume.
Funding: N/A
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PROSTATE CANCER TUMOR VOLUME AND GENOMIC RISK
Category
Prostate Cancer > Potentially Localized
Description
Poster #127
Thursday, December 1
2:00 p.m. - 3:00 p.m.
Presented By: Ashwin Ramaswamy
Authors:
Ashwin Ramaswamy
James A. Proudfoot
Ashley E. Ross
Elai Davicioni
Edward M Schaeffer
Jim C Hu