AbstractBackgroundNeoadjuvant platinum‐based chemotherapy offers a modest survival advantage in muscle‐invasive bladder cancer (MIBC) for patients with pathologic response. B7‐H3 (CD276), an immune checkpoint overexpressed in various cancers, including urothelial‐cell carcinoma (UCC), has been associated with chemoresistance and poor oncologic outcomes. We aimed to explore if B7H3 expression on bladder biopsy samples was a predictive biomarker for pathologic response to neoadjuvant platinum‐based chemotherapy.MethodsThis was a retrospective cohort study among MIBC patients receiving neoadjuvant platinum‐based chemotherapy followed by radical cystectomy. All patients underwent routine preoperative biopsy of their tumour. Immunohistochemistry was used to evaluate B7‐H3 expression from pre‐operative specimens. The primary outcome of interest was pathologic complete response (pCR). Statistical analysis included Mann–Whitney U test, Fisher's exact test, Kaplan–Meier method, and Cox regression for survival analysis.ResultsAmong 87 patients analysed, high B7‐H3 expression was found in 44.8% (n = 39) of patients. The median follow‐up periods were similar between the high and low B7‐H3 groups (high expression; 4.29 years [SD 3.04], low expression 3.94 years [SD 3.04], p = 0.60). Only 20.5% of patients with high B7‐H3 expression achieved pCR, compared to 41.7% in the low expression group (p = 0.04). Cox regression showed no significant differences in recurrence‐free or cancer‐specific survival between the high and low B7‐H3 expression groups (p > 0.05).ConclusionHigh B7‐H3 expression is associated with a reduced likelihood of achieving pCR in MIBC patients undergoing neoadjuvant chemotherapy. This suggests B7‐H3's potential as a predictive biomarker for chemotherapy response. Further research is needed to explore the role of B7‐H3 on platinum‐based chemotherapy response in urothelial cancer.
Impact of intraoperative tranexamic acid use on overall survival and cancer specific survival in patients undergoing radical cystectomy.
642 Background: Perioperative blood transfusion has been reported in up to 60% of patients undergoing RC. Unfortunately, perioperative blood transfusion in patient undergoing RC has been associated with poor oncological outcomes. Tranexamic acid (TXA) use has been proposed to decrease the need for perioperative blood transfusion. Here we seek to investigate the impact of intraoperative TXA on survival outcomes in patients undergoing radical cystectomy (RC) for bladder cancer. Methods: We queried the prospectively maintained Mayo Clinic Radical Cystectomy registry and identified all RC performed for bladder cancer between 1990-2021. Primary outcomes were patient’s overall survival and cancer specific survival among patients who received TXA versus patients who did not receive TXA. Results: Among 2929 patients who underwent RC in our institution between 1990-2021, 468 received TXA (IV) intraoperatively (Group A) and were propensity score matched 1:1 for age, neoadjuvant chemotherapy, adjuvant chemotherapy, pT stage, pN stage, and preoperative hemoglobin with a group who did not receive TXA (Group B, n= 468). At 8 years followup, 61% of patients who received TXA were alive versus 46% of patients who did not receive TXA. In univariable and multivariable analyses of factors associated with CSS (Table1), node positive disease, pT2-T4, peri-operative blood transfusion were associated with poor survival outcomes. While use of TXA was associated with improved CSS outcomes. Conclusions: In our study, TXA use in patients undergoing radical cystectomy was associated with decreased risk or peri-operative transfusion, improved patient’s overall survival, and cancer specific survival. We can’t explain the biological rational for improved survival however these findings warrant further prospective investigation. [Table: see text]
Safety of intraoperative tranexamic acid use on the risk of venous thromboembolism (VTE) in patients undergoing robotic assisted radical cystectomy (RARC).
641 Background: Perioperative blood transfusion is associated with an increased risk of adverse events and tranexamic acid (TXA) use has been proposed to decrease the need for perioperative blood transfusion. Herein, we seek to investigate the impact of intraoperative TXA on perioperative risk of VTE in a subset of patients who underwent robotic-assisted radical cystectomy (RARC) for bladder cancer. Methods: We queried the prospectively maintained Mayo Clinic Radical Cystectomy registry and identified patients who underwent RARC between 2004-2021 and received TXA intraoperatively. In univariable and multivariable analyses, we investigated factors associated with bleeding and VTE within 30 days post-operatively. Results: Of 2862 patients, we identified 94 patients who received TXA (IV) intraoperatively (Group A) and were propensity score matched 1:1 for age, neoadjuvant chemotherapy, pT stage, pN stage, and preoperative hemoglobin with a group who did not receive TXA; 38 patients (Group B). In univariable and multivariable models, use of TXA has no statistically significant impact on patient’s risk of bleeding or VTE. In a univariable model, number of positive lymph nodes and extent of lymph node dissection were associated with increased risk of VTE (Table 1). Conclusions: In our study, use of TXA in patient’s undergoing RARC was safe and was not associated with increased risk of VTE. [Table: see text]
Automated Identification of Key Steps in Robotic-Assisted Radical Prostatectomy Using Artificial Intelligence
Robotic-assisted radical prostatectomy (RARP) has become the leading approach for radical prostatectomy driven by innovations aimed at improving functional and oncological outcomes. The initial advancement in this field was transperitoneal multiport robotics, which has since undergone numerous technical modifications. These enhancements include the development of extraperitoneal, transperineal, and transvesical approaches to radical prostatectomy, greatly facilitated by the advent of the Single Port (SP) robot. This review offers a comprehensive analysis of these evolving techniques and their impact on RARP. Additionally, we explore the transformative role of artificial intelligence (AI) in digitizing robotic prostatectomy. AI advancements, particularly in automated surgical video analysis using computer vision technology, are unprecedented in their scope. These developments hold the potential to revolutionize surgeon feedback and assessment and transform surgical documentation, and they could lay the groundwork for real-time AI decision support during surgical procedures in the future. Furthermore, we discuss future robotic platforms and their potential to further enhance the field of RARP. Overall, the field of minimally invasive radical prostatectomy for prostate cancer has been an incubator of innovation over the last two decades. This review focuses on some recent developments in robotic prostatectomy, provides an overview of the next frontier in AI innovation during prostate cancer surgery, and highlights novel robotic platforms that may play an increasing role in prostate cancer surgery in the future.
Efficacy of
RestoreX
after prostatectomy: open‐label phase of a randomized controlled trial
Objective To report open‐label phase data from a recent randomized controlled trial (RCT), after previous data from that study showed improved penile length and erectile function among post‐prostatectomy men treated with Restorex penile traction therapy (RxPTT). Materials and Methods An RCT (NCT05244486) was performed to evaluate RxPTT vs no treatment (Tx) for 5 months, which was followed by a 3‐month open‐label phase. Men were stratified based on as‐treated data: Group 1 = No Tx; Group 2 = No Tx → Tx; Group 3 = Tx → No Tx; Group 4 = Tx. Assessments included stretched penile length and standardized (International Index of Erectile Function [IIEF]) and non‐standardized questionnaires. Results A total of 82 men were enrolled (mean age 58.6 years) with 9‐month data available in 45 of the men. Baseline characteristics were similar among the cohorts. Comparing Group 1 and Group 4 (respectively), notable differences included: IIEF Erectile Function domain (IIEF‐EF) score (−8 vs −0.5; P = 0.16), penile length (−0.1 vs +1.7 cm; P < 0.01), intracavernosal injection use (86% vs 14%; P < 0.01), Sexual Encounter Profile (SEP) Question 2 (50% vs 100%; P < 0.01), SEP Question 3 (33% vs 100%; P < 0.01). Men who crossed over to Tx (Group 2) failed to achieve equivalent improvements in length (+0.5 cm) or sexual function (IIEF‐EF score −6) compared to men treated early (Groups 3 and 4). Those who crossed over to no treatment after initial treatment (Group 3) experienced preserved length (+1.8 cm), and erectile function (IIEF‐EF score +0) despite therapy discontinuation. Conclusions Use of RxPTT beginning 1 month post‐prostatectomy results in improved penile length and erectile function, with benefits maintained after discontinuing therapy. If confirmed, these results represent the first postoperative therapy shown in a RCT to improve erectile function post‐prostatectomy. External validation is warranted.
Vesicourethral Anastomotic Stenosis Following Radical Prostatectomy: Risk Factors, Natural History, and Treatment Outcomes
Abstract Introduction: Muscle-Invasive Bladder Cancer (MIBC) is associated with a poor overall survival rate. One important factor that contributes to poor treatment outcomes is the histologic heterogeneity of MIBC tumors, which limits the translational value of some rodent models. As opposed to mice, dogs with spontaneously occurring bladder cancer have been shown to present with similar clinical behavior as human MIBC. In addition, canines have an intact immune system, which could provide for an ideal pre-clinical study population to investigate the efficacy of immunotherapy. In this study, we evaluated canine MIBC tumor biopsies for their similarities to human MIBC with regards to histology and immune cell infiltration. Materials & Methods: Nine canine MIBC tumor samples were provided by the ISU pathology service and evaluated by a human uropathologist. Canine MIBC tumors were phenotypically characterized using either immunofluorescence (IF) or RNA in situ hybridization (RNA-ISH), including CD44, KRT7 and FOXA1, as well as specific markers characterizing the immune cell infiltrate, such as CD163 (tumor-associated macrophages), CD8a (cytotoxic T-lymphocytes), PD-L1 (immune-checkpoint protein) and TGFβ2 (cancer-associated fibroblasts). Results: Histologically, all canine MIBCs were classified as invasive, high-grade urothelial carcinomas (UC) with identical morphology to human MIBC. Interestingly, previously described histological variants of human MIBC tumors were also observed within the canine MIBC samples, such as glandular differentiation in 3/9 canine MIBC samples; epithelial-mesenchymal transition with sarcomatoid differentiation 1/9, squamous differentiation in 2/9 and micropapillary carcinoma in 1/9, all of which have been associated with poor clinical outcomes in human patients. IF was strongly positive for KRT7, FOXA1 and CD44, and immune cell markers CD163 and TGFβ2. However, CD8a was only weakly expressed (5/9) or negative, and PD-L1 was only positive in 4/9 canine MIBC biopsies. Conclusions: Canine MIBC tumors showed significant heterogeneity with highly similar histological variant morphologies to those reported in humans with MIBC. Furthermore, phenotypic characterization of immune cell infiltrates and checkpoint proteins suggest that the tumors were typically immunologically “cold”. These data further establish the utility of the spontaneous canine model of MIBC for pre-clinical investigation of novel therapeutic drug candidates, including immunotherapies. Citation Format: Karin Allenspach, John Cheville, Hannah Wickham, Christopher Zdyrski, Vojtech Gabriel, Basant Ahmed, Mei-Jyun Ciou, Fabrice Lucien, Igor Frank, Olufemi Fasina, Pablo Pineyro, Johnathan P. Mochel. Similar variant histology and immune cell infiltration in canine and human muscle-invasive bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2509.
Evaluation of PD-L1 and B7-H3 expression as a predictor of response to adjuvant chemotherapy in bladder cancer.
548 Background: PD-L1 and B7-H3 have been found to be overexpressed in urothelial carcinoma (UC) of the urinary bladder. Recent studies have also demonstrated that B7-H3 and PD-L1 can promote resistance to platinum-based drugs but the predictive value of B7-H3 expression in patients treated with platinum-based chemotherapy is unknown. This study aims to investigate the association of PD-L1 and B7-H3 tumor expression with oncological outcomes in patients who underwent radical cystectomy (RC) and received subsequent adjuvant chemotherapy. Methods: Immunohistochemistry was performed on paraffin-embedded sections from bladder and lymph node specimens of 81 patients who had RC for bladder cancer. PD-L1 and B7-H3 expression on tumor cells was assessed by immunohistochemistry in both primary tumors and lymph node specimens. Association with clinicopathologic outcomes was determined using Fisher’s exact test and postoperative survival using Kaplan–Meier survival curves and Cox regression model. Results: B7-H3 expression in cystectomy specimens was more common than PD-L1 expression (72.8% vs. 35.8%). For both markers, no association was found with pathologic tumor stage, lymph node (LN) status, and histological subtype. Similar findings were observed for double-positive tumors (PD-L1+B7-H3+). Concordance between the primary tumor and patient-matched lymph nodes was found in 76.2% and 54.1% of patients for PD-L1 and B7-H3, respectively. PD-L1 tumor expression was not associated with oncologic outcomes. However, B7-H3 expression was associated with recurrence-free survival (HR: 2.38, 95% CI 1.06–5.31, p = 0.035) and cancer-specific survival (HR: 2.67, 95% CI 1.18–6.04, p = 0.019). Conclusions: In our single institutional study, B7-H3 is highly expressed in patients with UC treated with adjuvant chemotherapy and it was associated with decreased recurrence-free survival and cancer-specific survival. Pending further validation in larger cohorts, B7-H3 expression may function as a predictor of response to adjuvant chemotherapy and thus be useful in patient and regimen selection.
Intraoperative Blood Transfusion Is Associated With Increased Risk of Venous Thromboembolism After Radical Cystectomy