Citations

416 Background: Urethral recurrence (UR) has been reported to occur in up to 5% of patients following radical cystectomy (RC). Debate continues regarding the utility of screening for UR after RC. Moreover, oncologic outcomes of patients with UR remain incompletely described, and reports have been limited by small cohort sizes. Herein, we evaluated risk factors for UR as well as cancer-specific survival (CSS) and overall survival (OS) among patients with UR. Methods: We reviewed our institutional RC registry to identify patients with UR following RC. Logistic regression was used to assess risk factors for UR. Kaplan-Meier and Cox proportional hazard regression were used to compare outcomes in those with UR diagnosis prompted by symptoms versus those with asymptomatic UR diagnosed on surveillance cytology. Results: Overall, 2930 patients underwent RC from 1980-2018, with a median post-operative follow-up of 4.9 years (IQR 1.6-11.0), of whom 144 (4.9%) were subsequently diagnosed with UR. Prostatic urethral involvement at RC (odds ratio [OR] 5.75 [3.67-9.01], p < 0.0001) and higher pT-stage (OR 3.57 [2.07-6.14], p < 0.0001) were associated with an increased risk of UR, whereas receipt of continent urinary diversion (OR 0.34 [0.20-0.58], p < 0.0001) was associated with a decreased risk of UR. A total of 72/144 (50%) patients were diagnosed with UR based on symptoms, and 104/144 (72.2%) patients with UR underwent subsequent urethrectomy. Patients with symptomatic recurrence had higher tumor stage on urethrectomy than those with asymptomatic recurrence (≥pT2 in 13.1% vs 3.1%, p = 0.007). At a median follow-up of 2.6 years (IQR 1.0-7.1) after UR, 68 of the patients with UR died of urothelial carcinoma. Kaplan-Meier analyses suggest longer median overall and cancer-specific survival for patients with UR detected by cytology than those presenting with symptoms (p = 0.05 for both). On multivariable analyses, patients who experienced UR had significantly increased risk of cancer-specific (hazard ratio [HR] 1.93 [95% confidence interval 1.50-2.50), p < 0.0001) and all-cause mortality (HR 1.34 [1.13-1.65], p = 0.001). Conclusions: Approximately 5% of patient undergoing RC experience UR, with higher pT-stage and prostatic urethral involvement increasing the risk of UR. Asymptomatic detection of UR was associated with lower pathologic stage at urethrectomy as well as longer cancer-specific and overall survival, supporting urethral surveillance after RC.

405 Background: The diagnosis of upper tract urothelial carcinoma (UTUC) is frequently obtained via diagnostic ureteroscopy (URS) with biopsy. In a recent meta-analysis of five retrospective series comparing UTUC RNU patients with and without prior diagnostic URS, prior URS was associated with intravesical recurrence of urothelial carcinoma. However, there remains an incomplete understanding of the risks of URS on intravesical recurrence after RNU, and existing studies have not examined the risks of URS without endoscopic biopsy or percutaneous biopsy alone. Here, we query our institutional RNU registry to determine if UTUC diagnostic modality influences post-RNU intravesical recurrence risk. Methods: Years 1995 to 2019 of our institutions RNU registry were queried. Patients with UTUC were divided into four groups: 1) URS with endoscopic biopsy; 2) URS without endoscopic biopsy (visual confirmation alone); 3) percutaneous biopsy without any URS; 4) no URS and no percutaneous biopsy. Exclusion criteria included pure non-urothelial histology, RNU for benign indications, and prior/concomitant cystectomy. The primary outcome was intravesical recurrence of urothelial carcinoma compared across the four groups using Kaplan-Meier log-rank analyses and Cox-proportional hazard modeling (hazard ratio = HR). Results: In a cohort of 878 patients (mean post-RNU follow-up 43 months), 461 (53%) had URS with biopsy, 130 (15%) had URS without biopsy, 229 (26%) had no URS or percutaneous biopsy, and 58 (7%) had percutaneous biopsy alone. The 3-year intravesical recurrence rate was 27%, 22%, 18%, 12% for groups 1-4, respectively. Covariates associated with intravesical recurrence on univariable analysis included age (HR 1.03, p < 0.01), female gender (HR 0.76, p = 0.06), history of bladder cancer (HR 1.39, p = 0.01), current smoker (HR 1.49, p = 0.04), and multifocality (HR 1.34, p = 0.03). After adjusting for these covariates, multivariable analysis found that group 1 (URS with biopsy) was associated with increased intravesical recurrence (HR 1.41, p = 0.03) relative to group 3 (no URS or percutaneous biopsy). Compared to group 1, the hazard ratio for intravesical recurrence was not significantly different for group 2 (HR 1.18, p = 0.45) or group 4 (HR 1.11, p = 0.79). Conclusions: Patients undergoing ureteroscopic biopsy to diagnose UTUC prior to RNU had a higher risk of intravesical recurrence after RNU compared to patients who did not undergo any URS or percutaneous biopsy. This agrees with prior literature and suggests that aggressive ureteroscopic manipulation of UTUC tumors via biopsy may promote shedding of urothelial carcinoma cells capable of seeding the bladder. Our study does support the initiation of a randomized trial to determine if intravesical chemotherapy after ureteroscopic biopsy can reduce intravesical urothelial carcinoma recurrences.

Urinary bladder cancer (UBC) is the most common malignancy of the urinary tract in humans, with an estimated global prevalence of 1.1 million cases over 5 years. Because of its high rates of recurrence and resistance to chemotherapy, UBC is one of the most expensive cancers to treat, resulting in significant health care costs. The development of innovative molecular and cellular tools is necessary to refine patient stratification and help predict response to treatment. Urine is an underused resource of biological components shed from bladder tumors, such as exfoliated cells and extracellular vesicles, that could serve as molecular fingerprints and provide valuable biological insights into tumor phenotype and mechanisms of resistance to chemotherapy. Additionally, characterization of urine-derived extracellular vesicles and cells could be used as reliable biomarkers for prediction of response to neoadjuvant therapy.

e16103 Background: At present, androgen ablation (AA) therapy ± radiation therapy represents a first-line treatment for patients with unresectable locally advanced prostate cancer (CAP), typically resulting in palliative disease control. Immunotherapy, in the form of CTLA-4 blockade, has been shown to potentiate T-cell responses, representing a potential antitumoral immunotherapy for treating CAP. Here, we discuss the outcomes of 5 locally advanced CAP patients treated with the monoclonal antibody MDX-CTLA-4 (MDX-010) + AA who subsequently underwent radical prostatectomy (RP), 2 of whom exhibited striking down-staging of their disease. Methods: A Phase II trial testing AA + MDX-010 therapy for treatment of locally or systemically advanced CAP is currently ongoing at our institution. To date, 5/85 patients have electively opted for off-study RP with extended pelvic lymphadenectomy after documentation of robust treatment response by PSA, staging digital rectal exam, and 3-D imaging. Results: All men had unresectable, locally advanced disease (stage T2c-T4) prior to treatment with AA + MDX-010 and subsequently underwent RP. Median blood loss was 400mL (400–900). All patients had negative surgical margins. Of the 5 patients, 2 exhibited dramatic and indisputable down-staging of their disease. These two patients presented with 80% of biopsies involved with cancer, extraprostatic extension, seminal vesicle (SV) invasion, and bladder base involvement. On final pathology, both exhibited extensive treatment effect, remission of SV involvement, and robust disaggregation of solid tumors resulting in only microscopic, non-contiguous foci of residual intraprostatic cancer. Both had T4 disease pre-treatment, and had stage T2c on final pathology. One patient is free of disease with undetectable PSA for 19 months following adjuvant radiation treatment but no further therapy, while the other patient is awaiting follow-up. Conclusions: We have been able to demonstrate true down-staging of locally advanced prostate cancer with neoadjuvant AA + MDX-010 therapy. This therapeutic modality exhibits significant promise for men with unresectable disease and may provide durable and potentially curative cancer control. No significant financial relationships to disclose.

TPS3172 Background: Bladder cancer is a leading cause of cancer death in the United States. Over 90% of bladder cancer cases are urothelial carcinomas (UC) that may present as a non-muscle-invasive (NMIBC) or muscle-invasive disease (MIBC). Standard of care for NMIBC includes transurethral resection of bladder tumor (TURBT), intravesical chemotherapy and immunotherapy with Bacillus Calmette-Guerin (BCG). Patients (pts) with high-grade BCG-refractory NMIBC or MIBC undergo RC, which involves complete bladder removal and pelvic lymphadenectomy. RC severely impacts quality of life with significant morbidity. Oncolytic viruses are showing promise in UC, and MV-NIS has proven efficacy in other tumor types. MV-NIS is an investigational oncolytic measles virus with an excellent safety profile, irrespective of route of administration (n > 100). MV-NIS-related adverse events are limited to infusion reactions and transient CBC changes, and little local toxicity is anticipated with intravesical therapy. Clinical efficacy of this oncolytic may be related to absence of measles immunity. Based on this, the clinical strategy for MV-NIS is focused on targeting immune-privileged sites via intra-tumoral or intravesical routes, alone or in combination with checkpoint inhibitors. We hypothesize that intravesical therapy with oncolytic MV-NIS can improve clinical outcomes for (a) BCG refractory NMIBC pts to avoid or delay the need for RC; and (b) MIBC pts undergoing RC. Methods: This study is enrolling pts undergoing RC who are ineligible to receive neoadjuvant chemotherapy. The trial has 2 stages to (a) determine the safety and tolerability of intravesical MV-NIS, and (b) assess preliminary efficacy. Part (a) includes 4-24 pts in a timing cohort with doses administered at increasing durations (1-4 weeks) prior to RC to establish safety of a single MV-NIS dose. Part (b) includes an expansion cohort (n = 12) to evaluate the safety and efficacy of 2 intravesical doses of MV-NIS at 2-week intervals prior to RC. Safety is assessed using NCI-CTCAE V5 and Clavien-Dindo grading of operative complications. The efficacy endpoint is pathologic stage at time of RC (pT0 rate), which can be compared to pre-study TURBT stage. Additional exploratory studies include PK and PD analyses in urine, blood and tumor. Enrollment is ongoing at 2 Mayo Clinic sites (Rochester, MN and Jacksonville, FL) and the study has now progressed from the timing cohort into the expansion cohort. Clinical trial information: NCT03171493 .

5117 Background: Prognostic nomograms, scoring tools, and risk tables are rapidly accumulating in the prostate cancer (PCa) literature. It is not always clear to whom these tools should apply and how well they predict the outcomes they were designed to forecast. There is need for independent evaluation of these tools. Methods: We used the Mayo Clinic Radical Prostatectomy Registry, a prospective database of radical prostatectomy (RP) outcomes, to assess tools designed to predict RP outcomes. The validation set included 13,313 RP patients from 1990–2005. There were 3,256 PSA failures, 566 metastases, and 1,599 deaths (301 were due to PCa). We assessed the discrimination, calibration and overall accuracy of prediction tools identified through a structured Pubmed search. Results: Tools varied greatly in terms of complexity, width of prediction interval, and method of presentation. Several tools included non-standard variables and were therefore unevaluable, despite an extensive dataset, leaving the 1999 and 2005 Kattan nomograms, the 1998 and 2001 CDPR scores, and the 2001 GPSM score for analysis. Discrimination (quantitated by the c index) was better for PCa-specific survival and metastases than for PSA failure ( Table ). Kaplan-Meier plots demonstrated clustering of risk groups in most tools, most severely in the higher risk groups of the Kattan nomograms. The calibration plots of most tools (excepting GPSM) had a serious discordance between observed and predicted outcomes in the lower probability ranges. This meant that most tools gravely overestimated the probability of RP failure in high-risk patients, by up to 4- fold. Conclusions: The tools showed moderate discriminatory ability for PSA failure but performed much better for non-surrogate outcomes. Most tools (excepting GPSM) were miscalibrated in high risk patients and dramatically underestimated the efficacy of surgery in this cohort. Prognostic tools may not be as accurate as previously reported. [Table: see text] No significant financial relationships to disclose.

483 Background: We evaluate the impact of salvage intravesical therapy on survival in patients with NMIBC previously treated with BCG who ultimately underwent radical cystectomy (RC). Methods: We retrospectively identified patients with NMIBC who received at least 1 complete induction course of BCG and subsequently underwent RC for bladder cancer between 2000-2018. Patients were stratified by receipt of salvage intravesical therapy following BCG prior to RC. Oncologic outcomes were compared using Cox proportional hazards regression analysis and the Kaplan-Meier method. Results: We identified 371 patients who underwent RC after receiving BCG, of whom 55 (15%) received salvage intravesical therapy, most commonly Mitomycin C (n = 26), Valrubicin (n = 8), Gemcitabine (n = 7), and CG0070 (n = 6). Median follow-up among survivors was 1.1 (IQR 0-4.3) years. Patients who received salvage intravesical therapy were more likely to initially present with CIS (27% vs 17%) and less likely to present with T1 disease (33% vs 50%, both p < 0.05). Receipt of salvage intravesical therapy was not associated with increased risk of adverse pathology (≥pT2 or pN+) at RC (33% vs 41%, p = 0.27). Furthermore, on Kaplan-Meier analysis, receipt of salvage intravesical therapy was not associated with cancer-specific or overall survival. On multivariable Cox proportional hazards regression, clinical stage prior to RC, but not receipt of salvage intravesical therapy, was associated with inferior cancer-specific survival and overall survival. Conclusions: Our results suggest that RC following carefully managed salvage intravesical therapy after BCG is not associated with inferior oncologic outcomes, which can improve patient counseling. [Table: see text]

SAGE-Journals-Accessible-Video-Player 10.1089/vid.2018.0051.M1 sj-vid-1-vid-10.1089_vid.2018.0051