Abstracts from the New England Section of the AUA 2020: A Virtual Experience

© The Canadian Journal of Urology TM : International Supplement, August 2020 39 The Impact of Pre-Treatment PSAon Risk Stratification inMen with Gleason 6 Prostate Cancer: Implications for Active Surveillance Sina Monfared, BS 1 , Aaron Fleishman, MPH 2 , Ruslan Korets, MD 2 , Peter Chang, MD, MPH 2 , Andrew Wagner, MD 2 , Glenn Bubley, MD 2 , Irving Kaplan, MD 2 , Aria Olumi, MD 2 , Boris Gershman, MD 2 1 Boston University School of Medicine, Boston, MA; 2 Beth Israel Deaconess Medical Center, Boston, MA Introduction: The optimal treatment for men with Gleason 6 prostate cancer and a PSA above 10 ng/mL is uncertain. Although active surveillance is the preferred management strategy for menwith low-risk disease, there are limited data to support the safety of active surveillance in men with favorable-intermediate risk disease due only to a discordant PSA above 10 ng/mL. We therefore evaluated the impact of pre-treatment PSA on risk- stratification in men with Gleason 6 prostate cancer. Materials &Methods: We identified men aged 18-75 with cT1-2 cN0 cM0, pre-treatment PSA < 20 ng/mL, Gleason 6 prostate cancer diagnosed from 2010-2016 in the National Cancer Database (NCDB) who underwent radical prostatectomy. The primary outcomes were Gleason score upgrading to 7-10 and adverse pathologic features at prostatectomy (i.e., pT3a, pT3b, or pN1). The associations of patient and disease features with each outcome were evaluated using bivariate analyses as well as univariable andmultivariable logisticregression.Toevaluatefornon-linearrelationshipsbetweenPSAandeachoutcome, we examined predictedmarginal event rates standardized for baseline characteristics with PSAmodeled using restricted cubic splines with four knots. Results: Atotalof79,036patientswere included inthecohort.Meanageatdiagnosiswas59.5 (SD6.8)years,andmedianpre-treatmentPSAwas5.1(IQR4.1-6.8)ng/mL.Atprostatectomy, Gleason score upgrading was identified in 49.7% of patients, including 41.2%with Gleason 3+4, 5.3%with Gleason 4+3, and 1.5%with Gleason 8-10.Adverse pathologic features were identified in 10.5% of patients, including 8.9% with pT3a disease, 1.4% with pT3b disease, and 0.2% with pN1 disease. In unadjusted analyses, patients with pre-treatment PSA ≥ 10 ng/mLhad higher ratesof Gleason coreupgrading (58.8%vs. 47.9%,p <0.001) and adverse pathologic features (19.7% vs. 10.0%, p < 0.001) compared to patients with a PSA < 10 ng/ mL. In multivariable analyses that adjusted for patient and disease features, PSA ≥ 10 ng/ mLwasassociatedwithstatisticallysignificantly increasedrisksofGleasonscoreupgrading (OR 1.47, 95% CI 1.39-1.55) and adverse pathologic features (OR 2.14, 95% CI 2.00-2.29). When modeled as a non-linear continuous covariate, PSA was associated with increased adjustedratesofGleasonscoreupgrading(Figure1)andadversepathologicfeatures(Figure 2) without a clear dichotomization at a threshold of 10 ng/mL. Conclusions: In this surgical cohort, higher pre-treatment PSA was independently associated with increased risks of Gleason score upgrading and adverse pathological features at prostatectomy in men with Gleason 6 prostate cancer. Flexible modeling of the relationship between PSA and each outcome did not support dichotomization at a threshold of 10 ng/mL. These results can be used to improve patient risk-stratification for active surveillance. Risk Stratification by Prostate Health Index Prior to MRI-Ultrasound Fusion Targeted Biopsy Benjamin Press, MD , Ghazal Khajir, MD, Michael S. Leapman, MD, Preston Sprenkle, MD Yale University School of Medicine, New Haven, CT Introduction: Serum biomarkers that improve upon prostate specific antigen (PSA) for the prediction of prostate cancer, and may therefore help improve selection for prostate biopsy. Limited information exists to guide how these tools should be integrated in the context of prostate magnetic resonance imaging (MRI) in the MR-targeted biopsy era. We aimed to identify a biomarker threshold for the detection of GG2 or higher prostate cancer at MRI ultrasound fusion-targeted biopsy (MRF-TB). Materials & Methods: Between June 2015 and July 2019, 192 men received biomarker testing with the prostate health index (phi), a measurement that combines %free PSA, total PSA, and the -2proPSA isoform of PSA, prior to undergoing MRF-TB at our institution. Findings on prostate biopsy (including Grade Group [GG]), PI-RADS, and phi were prospectively recorded. Cancer detection rates (CDR) at pre-determined phi ranges were evaluated. The interaction of PI-RADS and phi was also evaluated at phi level of 27 (previously reported and widely used cutoff) versus the phi cutoff value calculated at our institution. Results: The median phi score was 51 (interquartile range 36-70). Sensitivity of phi for detecting any prostate cancer at a cutoff of 27 and 36 was 92.54% and 85.82%, respectively. Sensitivity of phi for detecting any GG2 or higher prostate cancer at a cutoff of 27 and 36 was 95.06% and 88.89%, respectively. In the subset of men with PSA between 4 and 10 ng/mL, CDR of GG2 and higher prostate cancer was significantly higher at a phi > 36 than < 36 (18.7 vs. 47.8%, p = 0.01) (Table 1). Among all men who obtained phi prior to MRF-TB, no men who had PI-RADS ≤ 3 and a negative phi were found to have GG2 or higher prostate cancer both at phi cutoffs of 27 and 36 (Table 2). Conclusions: We evaluated the performance of the prostate health index among patients with suspicion of prostate cancer undergoingMRI ultrasound fusion biopsy. This analysis supports the use of a phi cutoff of ≤ 36 to avoid biopsy among patients whose prostate MRI has a low suspicion for prostate cancer. 38 18 Scientific Session IV: Oncology II