Utilization of genomic prostate score with prostate specific antigen density in patients on active surveillance for low-risk prostate cancer

Philadelphia, PA

Introduction and objectives: Prostate cancer is prevalent in men and the second leading cause of cancer related death. However, not all prostate cancer is lethal. and active surveillance is an accepted treatment approach in appropriately risk stratified patients. Nonetheless, there is a subset of patients on active surveillance (AS) that escalates to treatment and a paucity of data to identify patients requiring treatment intensification Biomarkers such as Oncotype DX have been utilized in multiple malignancies including prostate cancer and aid in shared decision-making regarding treatment. In this study, we present real world data on the use of Oncotype DX Genomic Prostate Score (GPS) and the likelihood of progression to treatment in prostate cancer patients on AS.

Methods: A multi-institutional retrospective chart review was performed from 2017-2024 for patients with low-risk prostate cancer on AS. Thos patients that escalated to treatment (surgery, radiation, or hormonal therapy) were compared to those that stayed on active surveillance. Patient demographics, prostate biopsy specific data, GPS data, and PSAD was analyzed between the two groups. Descriptive analysis was performed using t-test for continuous variables and Chi-square for categorical variables and a multivariate logistic regression was performed to predict progression.

Results: A total of 301 patients were included in the study, and among the total, 34.6% of patients escalated to treatment while 65.4% stayed on AS. There was no difference in mean age of diagnosis, race, and family history. Factors associated with progression to treatment included a higher GPS score was noted (21.6 vs. 17.2) for the treatment group. On the adjusted analysis, number of positive cores (OR 2.15, SD 1.25 - 3.72, p< 0.01), GPS (OR 1.21, SD 1 - 1.47, P = 0.05), and HLD (OR 3.41, SD 1.93 - 6.24, P< 0.001) (Figure 1). There were no statistical differences with % high grade disease, % risk of metastasis, % non-organ confined, and PSAD. On the ROC curve, we show that GPS had higher sensitivity and specificity for predicting escalation to treatment compared to PSAD or PSAD with GPS (Figure 2).

Conclusions: GPS can be a predictive biomarker for those patients on active surveillance for prostate cancer. We show that the mean score for the treatment group was 21.6 compared to the 17.2 of the AS group. Shared decision making with the patients after risk stratification can be vital in low-risk prostate cancer. We show that the number of cores positive, HLD, and GPS are the independent factors associated with progression to treatment. The addition of PSAD to GPS score does not significantly improve the ability to predict those patients on AS who progress to treatment.