(UroToday.com) The 2023 American Urological Association (AUA) annual meeting held in Chicago, IL between April 28 and May 1st, 2023, was host to a prostate cancer detection and screening moderated poster session. Dr. Alec Zhu presented the results of an analysis evaluating the use of Decipher® prostate biopsy testing in men with favorable-risk prostate cancer undergoing conservative management in The Surveillance, Epidemiology, and End Results (SEER) registry.
Recently, results of the Decipher 22-gene expression classifier (GC) for men with prostate cancer has become available for SEER registry individuals. It remains unclear whether the use of the Decipher GC is associated with management changes at a population level. As such, the objective of this study was to evaluate the use of conservative management (active surveillance/watchful waiting) in both GC tested and untested men and evaluate factors, including Decipher GC score, associated with adverse pathology at radical prostatectomy, defined as grade group 3 or worse disease, pathological stage pT3b or worse, or pathologic lymph node involvement.
The investigators identified men with favorable risk (i.e., Grade Group 1 and 2) prostate cancer from the SEER registry, diagnosed between 2016 and 2018. Available Decipher GC data from 2016 to 2020 (Veracyte, San Diego, CA) was subsequently linked to patients in this cohort. Decipher GC scores ranged between 0 and 1 (continuous variable), and this variable was further operationalized as a categorical variable: low, intermediate, and high-risk groups. The association between Decipher GC test results and the odds of undergoing conservative management, as well as the association between GC test results and the odds of adverse pathology on radical prostatectomy, were evaluated using multivariable logistic regression analyses.
This analysis included a total of 100,279 men of whom 2,889 underwent Decipher GC testing at biopsy (97,390 were untested).
Between 2016 and 2018, the utilization of conservative management increased from 20% to 23% in untested men, compared to 33% to 37% in tested patients. The corresponding figures in men aged <70 years were 20% to 24 and 35% to 37%, respectively. On multivariable analysis, Decipher GC testing was associated with significantly increased odds of conservative management utilization (OR: 2.1, 95% CI: 1.9 – 2.4, p<0.001). Conservative management use was highest for GC low-risk men (41%), followed by intermediate- (31%), and high-risk men (16%). Both higher Decipher GC score and percentage of positive cores, a surrogate of disease volume, were significantly associated with increased odds of undergoing a radical prostatectomy. However, for men treated with a radical prostatectomy, only higher GC score was significantly associated with increased odds of adverse pathology.
Dr. Zhu concluded that Decipher® GC testing was independently associated with a two-fold increase in the odds of conservative management utilization for favorable-risk prostate cancer patients. Men with lower Decipher GC scores had increased odds of undergoing conservative management. Both higher GC scores and tumor volume were associated with increased odds of undergoing a radical prostatectomy. However, only higher Decipher GC score was associated with significantly increased odds of adverse pathology on radical prostatectomy, whereas increased tumor volume was not.
Presented by: Alec Zhu, MD, Urology Resident Physician, Department of Urology, Weil Cornell Urology, New York, NY
Written by: Rashid K. Sayyid, MD, MSc – Society of Urologic Oncology (SUO) Clinical Fellow at The University of Toronto, @rksayyid on Twitter during the 2023 American Urological Association (AUA) Annual Meeting, Chicago, IL, April 27 – May 1, 2023