Abstracts from the New England Section of the AUA 2021

© The Canadian Journal of Urology TM : International Supplement, October 2021 Concurrent Scientific Session IV: Oncology II 42 The NCDB Forgot about DRE? Esther L. Finney, MD 1 , Harras B. Zaid, MD 1 , David Canes, MD 1 , Alireza Moinzadeh, MD, MBA 1 , Kristian B. Stensland, MD, MPH 2 1 Lahey Hospital and Medical Center, Burlington, MA, USA; 2 University of Michigan, Ann Arbor, MI, USA Introduction: The digital rectal exam (DRE) is currently included in the AUA/NCCN risk strata for prostate cancer. Specifically, a patient cannot be “low risk” if they have palpable disease in more than half of one side of the prostate (cT2b or higher), which may render them ineligible for surveillance or other lower intensity treatments. However, it is unclear how frequently DRE findings are reported, particularly with respect to substaging (i.e., cT2a, cT2b, cT2c). We hypothesized that there is no documentation of tumor substage for a large number of patients, and that the rate of reporting has decreased over the last decade. Materials & Methods: We queried the National Cancer Database for nonmetastatic prostate cancer cases from2004-2016. We evaluated the number of cases missing clinical T2 substaging for each year (cTx). To estimate the potential change in risk grouping if DREwere missing, we also calculated the number of patients whose risk stratification would change based on clinical exam alone (i.e., PSA and Gleason score) for patients whose Gleason Grade Group, PSA, and clinical T2 substage were available. Results: A total of 335,852 cases were included, of which 65,376 (20%) were missing a substage. The rate of missing substage documentation increased from 15% of cT2 cases in 2004 to 25% in 2015, then dropped to 10% in 2016. Of the patients with available cT2 substage (cT2a-c), 2,591 (11%) of 23,706 otherwise low risk patients were upstaged to unfavorable intermediate risk based on DRE alone. Similarly, of 30,385 otherwise favorable intermediate risk patients, 8,479 (28%) were upstaged to unfavorable intermediate risk based on DRE alone. Conclusions: One in five prostate cancer cases ismissing clinical T substaging, knowledge of which changes risk stratification in 20% of patients with otherwise low or favorable intermediate risk. This disconnect may reflect poor recording or reporting of DRE for palpable disease, or suggests that this level of accuracy in the DRE for risk stratification purposes may need to be reevaluated. Even if this finding only applies to the NCDB, given one in five localized prostate cancer cases is missing key staging information, use of the AUA/NCCN risk stratification with the NCDB should be done with caution. MRI Monitoring for Focal Ablation Series James Nie, BS , SoumLokeshwar, MD-MBA, Daniel Segal, MD, Ghazal Khajir, MD, Benjamin Press, MD, Preston Sprenkle, MD Yale School of Medicine, New Haven, CT, USA Introduction: We report the utility of MRI-based follow-up and short-term outcomes of primary focal ablation for localized low-risk prostate cancer (PCa). Materials & Methods: We conducted retrospective analysis of 19 men who underwent focal targeted cryoablation (n=16) or Nanoknife electroporation (n=3) from 2014-20. MRI-US fusion biopsy (FBx) and systematic core needle biopsy were conducted at 6 and 24 months. Clinically significant PCa was defined as >GG2. Biochemical recurrence was defined by Phoenix criteria. Treatment failure was defined by radical prostatectomy (RP), radiation therapy, or repeat ablation. Results: Median age, PSA, and prostate volume at ablation were 64 years, 8.2ng/mL, and 53cc. Pre-ablation highest grade was grade group 1 (GG1) in 4 men, GG2 in 10, and GG3 in 5. Median followupwas 25.5 months. Two weeks after ablation, 1 high-risk patient (PSA>20) exhibited residual PIRADs-5 lesion and underwent RP. 16 patients underwent 6-month FBx (median: 6.9months). On MRI, no suspicious lesions were visualized in the ablation zone, but 1/16 (6.3%) patients had GG4 disease in the ablation cavity. 2/16 (12.5%) patients developed contralateral (CL) MRI-visible lesions, but no corresponding csPCa on Fbx.10 patients had second Fbx (median: 24.1 months). 1 patient (10%) exhibited a PIRADs-4 lesion in the ablation zone but no csPCa. 1 patient (10%) had two CL PIRADs-4 lesions without corresponding csPCa, but had an un-visualized ipsilateral GG2cancer. 2 additional patients had un-visualized cancers: 1 (10%) with GG2 in the ablation zone and 1 (10%) with an ipsilateral GG2 cancer. 3 patients underwent RP, 2 radiation, and 1 ablation for CL recurrence. Mean pre-ablation PSAD for patients with treatment failure was 0.24, compared to 0.17 for those without. No new or worsening urinary incontinence occurred, but 4/19 patients had new/ worsening erectile dysfunction. 1/19 patients were lost to follow[NJ1] up, but all other patients without treatment failure continue on PSAsurveillance without evidence of BCR. Conclusions: For primary focal ablation, MRI based monitoring alone may be insufficient for monitoring disease recurrence. None of the 4 patients with csPCa detected on biopsy had corresponding lesions detected onMRI. Patients with higher pre-ablation PSADmay be at more risk for treatment failure. We report a 24-month salvage treatment free rate of 68.4%. 41 22