Genomic Prostate Score (GPS), a 17-gene molecular assay, strongly and independently predicts adverse pathology and time to biochemical recurrence in men with low- to intermediate-risk prostate cancer (PCa), a new study confirms.
Investigators led by Jennifer Cullen, MPh, PhD, of the Department of Defense, Center for Prostate Disease Research, in Rockville, Md., tested the validity of GPS using biopsies from 431 men with very low to intermediate-risk PCa from 2 U.S. military medical centers. The researchers assessed GPS’ abilities to predict adverse pathology at radical prostatectomy, biochemical recurrence, and metastasis.
According to findings published in European Urology, 163 men had adverse pathology, 62 experienced biochemical recurrence, and 5 developed metastases during a median 5-year follow up period. GPS predicted time to biochemical recurrence and time to metastasis. GPS was also strongly linked with adverse pathology and predicted both high-grade (primary Gleason pattern 4 or any pattern 5) and non-organ-confined disease (pT3). Notably, GPS was predictive for both Caucasian and African American patients (other racial groups were not adequately represented).
The strong independent association of GPS with these near- and longer-term clinical endpoints “establishes this assay as a robust measure of PCa aggressiveness,” the researchers stated. The test predicted both early and late biochemical recurrence and metastasis. Together, GPS gives physicians a “more accurate risk assessment to guide treatment decisions for men with newly diagnosed disease.”
The GPS assay includes genes representing “multiple, distinct biologic pathways involved in prostate tumorigenesis,” the researchers noted. All 4 gene groups predicted adverse pathology in this study. Downregulation of androgen signaling and upregulation of stromal response gene groups were also strongly linked with time to biochemical recurrence.