Bladder Preservation Rate Research Articles

Bladder Tumor-Focused Adaptive Radiation Therapy: Clinical Outcomes of a Phase I Dose Escalation Study

Purpose/ObjectivesWe determine the maximum tolerated tumour focused dose (MTD) for the radical treatment of muscle invasive bladder cancer (MIBC) enabled by image guided adaptive radiotherapy (IGART) and long-term clinical outcomes. Materials/Methods: Fifty-nine patients with T2-T4aN0M0 unifocal urothelial MIBC suitable for daily radical radiotherapy were recruited prospectively to an ethics approved protocol (XX). The uninvolved bladder (PTVbladder) was planned to 52Gy in 32 fractions (f). The bladder tumour (PTVtumour) was planned to an assigned dose level of 68, 70, 72, or 74Gy. If organ at risk (OAR) dose constraints were violated, then PTVtumour was planned to 64Gy. Dose level allocation was determined by concurrent toxicity assessment of all previous patients recruited. Acute toxicity was evaluated using CTCAE v3.0; late toxicity was evaluated using RTOG criteria. The MTD was predefined as the highest dose level with estimated probability of ≤ 15% ≥G3 late toxicity and observed rate <50% acute G3 and <10% acute G4 toxicity. ResultsTwenty-six patients were assigned to 68Gy, of whom 6 were planned to 64Gy; 29 patients were assigned to 70Gy of whom 1 was planned to 68Gy, 2 patients were assigned and planned to 72Gy; no patients were assigned to 74Gy. Three patients did not complete treatment as planned, of whom only 1 patient stopped treatment because dose limiting toxicity occurred. The MTD was 70Gy. Acute genitourinary (GU) and gastrointestinal (GI) G3 acute toxicity was seen in 19% and 7% patients respectively. No grade 4 GU or GI toxicity was seen. Late toxicity (any) G3 and G4 was seen in 14% and 2% patients respectively. The 5-year overall survival was 58% (95% CI 44-71%). The bladder preservation rate was 89% (95% CI, 88 to 96%) with 6 patients not retaining native bladder function. ConclusionBladder tumour focused dose escalation to 70Gy using IGART is feasible with acceptable toxicity. This dose level has been evaluated in a phase II randomised control trial (XXXXX).

Abstract IA012: Novel approaches to the management of non-muscle invasive bladder cancer

Abstract Non-muscle invasive bladder cancer (NMIBC) is a prevalent disease with a high recurrence rate and the potential to progress to muscle-invasive stages. While transurethral resection and bacillus Calmette-Guerin (BCG) immunotherapy remain the mainstay of treatment, limitations exist, particularly for high-grade and BCG-unresponsive NMIBC. This necessitates the exploration of novel therapeutic strategies. This talk will explore promising avenues in NMIBC management, including combination intravesical therapies, enhanced delivery methods for existing treatments, and emerging fields like gene therapy, targeted therapy, immunotherapy variants, and photodynamic therapy. These approaches hold the potential to improve bladder preservation rates, reduce recurrence, and ultimately enhance patient outcomes across the entire spectrum of NMIBC disease. Citation Format: Ashish M. Kamat. Novel approaches to the management of non-muscle invasive bladder cancer [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr IA012.

Disitamab Vedotin Alone or in Combination With Immune Checkpoint Inhibitors in Bladder-Sparing Treatment of Muscle-Invasive Bladder Cancer: A Real-World Study

PurposeTo evaluate the efficacy and safety of a novel humanized anti-HER2 antibody, RC48-ADC (Disitamab vedotin, DV), the combination of RC48-ADC with PD-1 inhibitors was used to treat muscle-invasive bladder cancer (MIBC). This combination therapy has potential applications in both bladder preservation and neoadjuvant therapy for MIBC. MethodsPatients with MIBC underwent transurethral resection of bladder tumors followed by RC48-ADC alone or in combination with PD-1 inhibitors. Radiological and endoscopic evaluations were conducted 3 months later. The primary endpoint was objective response rate (ORR), with secondary endpoints including complete response rate (CR), partial response rate (PR), and bladder preservation rate. Treatment safety was assessed according to RECIST v1.1 criteria. ResultsEleven patients were enrolled, with a median follow-up of 19.0 months. Nine patients achieved objective response, including 6 CR and 3 PR cases. The pathological ORR was 81.8%. Eight patients continued combined treatment after 3 months, maintaining a 72.7% bladder preservation rate at 16 months. One elderly patient progressed from ypT2N0M0 to ypT3N0M0 and underwent radical cystectomy but had no recurrence or metastasis 12 months postoperation. All patients reported varying degrees of treatment-related adverse reactions, which were largely manageable. ConclusionThe combination of RC48-ADC and PD-1 inhibitors proves to be a viable and safe option for bladder-sparing therapy, particularly for T2-stage MIBC patients who are ineligible for surgery and chemotherapy. This approach offers a promising new direction for bladder preservation or neoadjuvant therapy in MIBC patients.

Cost-effectiveness analysis of different treatment modalities in BCG-unresponsive NMIBC.

Radical cystectomy (RC) is the standard of care (SOC) in BCG-unresponsive NMIBC and is associated with a significant health-related quality-of-life burden. Recently, promising results have been published on Gemcitabine/Docetaxel, Pembrolizumab, and Hyperthermic Intravesical Chemotherapy (HIVEC) as salvage therapy options trying to increase the rate of bladder preservation. Here, we performed a Cost-Effectiveness-Analysis of those treatment modalities. We developed a Markov model from a payer's perspective drawing on clinical data of single-arm trials testing intravesical gemcitabine/docetaxel and pembrolizumab in BCG-unresponsive NMIBC, as well as clinical data from patients receiving hyperthermic intravesical chemotherapy HIVEC (n = 29) as intravesical salvage chemotherapy at our uro-oncological centre in Cologne. Costs were simulated utilising a non-commercial diagnosis-related groups grouper, utilities were derived from comparable cost-effectiveness studies. We used a Monte Carlo simulation to identify the optimal treatment, comparing the incremental cost effectiveness ratios (ICERs) at a willingness-to-pay threshold of €50 000 (euro)/quality-adjusted life year (QALY). Over a horizon of 10 years, gemcitabine/docetaxel, HIVEC, and pembrolizumab were associated with costs of €48 353, €64 438, and €204 580, as well as a gain of QALYs of 6.16, 6.48, and 6.00, resulting in an ICER of €26 482, €42 567, and €184 533 respectively, in comparison to RC with total costs of €21 871 and a gain of QALYs of 5.01. Monte Carlo simulation identified HIVEC as the treatment of choice under assumption of a WTP of <€50 000. Considering a WTP of <€50 000/QALY, gemcitabine/docetaxel and HIVEC are highly cost-effective therapeutic options in BCG-refractory NMIBC, while RC remains the cheapest option. At its current price, pembrolizumab would only be cost-effective assuming a price reduction of at least 70%.

Cost-effectiveness-analysis of different treatment modalities in bacillus Calmette-Guérin (BCG) unresponsive non-muscle invasive bladder cancer (NIMBC).

556 Background: Elaborate treatment and repetitive surveillance makes bladder cancer to the most expensive cancer type over the lifetime of a patient with a peak in non-muscle invasive bladder cancer. Radical cystectomy (RC) as the Standard of Care in BCG unresponsive NMIBC is associated with a significant health-related quality-of-life burden (QALY). Gemcitabine/Docetaxel, Pembrolizumab or Hyperthermic Intravesical Chemotherapy (HIVEC) have recently been published as salvage treatment options trying to increase the rate of bladder preservation. Methods: We developed a Markov model from a payer´s perspective with the clinical data of single-arm studies for BCG unresponsive NMIBC (Gemcitabine/Docetaxel and Pembrolizumab) and our clinical data for patients receiving HIVEC (n=29) as intravesical salvage-chemotherapy. Costs were simulated with a non-commercial DRG-grouper, utilities were derived from comparable cost-effectiveness studies. We used a Monte-Carlo Simulation to identify the optimal treatment, comparing the incremental cost effectiveness ratios (ICER) in consideration of a willingness-to pay of 50.000 Euro/QALY. Results: Over a horizon of 10 years, Gemcitabine/Docetaxel, HIVEC and Pembrolizumab were associated with costs of 48.353 64.438 and 204.580 Euro, and QALY´s of 6.16, 6.48 and 6.00, resulting in an ICER of 26.482, 42.567 and 184.533 Euro in comparison to RC (costs: 21.871 Euro; QALY: 5.01). Monte-Carlo Simulation has identified HIVEC as the treatment of choice in the assumption of a WTP of &lt;50.000 Euro. QALY gains in Gemcitabine/Docetaxel and especially HIVEC were mainly driven by bladder preservation and the low rate of progression. Conclusions: Considering a WTP of &lt;50.000 Euro / QALY, Gemcitabine/Docetaxel and HIVEC are highly cost-effective therapy options in BCG unresponsive bladder cancer, while RC remains the cheapest option. At its current price, Pembrolizumab is only cost-effective with a price reduction of 70%.

Radiotherapy combined with deep regional hyperthermia in elderly and frail patients with muscle-invasive bladder cancer: quality analysis of hyperthermia and impact on clinical results

Purpose: Radiotherapy (RT) in combination with deep regional hyperthermia (HT) after transurethral removal of bladder tumor (TURBT) can be offered to elderly and frail patients with muscle-invasive bladder cancer (MIBC). Methods: In total, 21 patients (mean age 84 years) with unifocal or multifocal MIBC received radiation to a dose of 48–50 Gy/16–20 fractions with weekly HT. The primary endpoint was the variation in temperature metrics, thermal dose expressed as cumulative equivalent minutes at 43 °C when the measured temperature is T90 (CEM43T90) and net power applied in target volume per each HT session. Secondary endpoints were three-year overall survival (OS), disease-free survival (DFS), local progression-free survival (LPFS) and toxicity. Results: The temperature metrics, CEM43T90, mean and maximum net power applied did not differ significantly among the HT sessions of the 21 patients. With a median follow-up of 65 months, 52% (95% CI 32–72%) of patients had died 3 years after treatment. The three-year DFS and LPFS rates were 62% (95%CI 41–79%) and 81% (95%CI 60–92%), respectively. The three-year bladder preservation rate was 100%. Three out of four patients with local failure received a thermal dose CEM43T90 below a median of 2.4 min. The rates of acute and late grade-3 toxicities were 10% and 14%, respectively. Conclusion: The reproducibility of HT parameters between sessions was high. A moderately high CEM43T90 (> 2.4 min) for each HT session seems to be preferable for local control. RT combined with HT is a promising organ-preservation therapy for elderly and frail MIBC patients.

The preliminary efficacy of "quadri-combination" therapy on the treatment of bladder cancer

To investigate the safety and efficacy of "quadri-combination" therapy including maximal transurethral resection of bladder tumor (mTURBT), combined with systemic chemotherapy and immunotherapy, concurrent radiotherapy, and immune maintenance therapy. The clinical data of 8 patients with bladder cancer who could not tolerate or refused radical cystectomy at the Department of Urology, Peking University Cancer Hospital from November 2019 to October 2021 were retrospectively analyzed. There were 5 males and 3 females with a mean age of 69 years. The Eastern Cooperative Oncology Group(ECOG) score was 0 in 6 cases and 1 in 2 cases. There were 5 cases of high-grade urothelial carcinoma (1 case of T3b; 2 cases were T2; 2 cases of T1 stage, with multiple tumors and repeated recurrence), 1 case of high-grade urothelial carcinoma with carcinoma in situ (T1/Tis stage), 1 case of high-grade urothelial carcinoma with squamous differentiation (T3b stage), and 1 case of high-grade urothelial carcinoma with glandular differentiation (T2). All patients underwent "quadri-combination" therapy.The patient's tolerance, success rate of bladder preservation and prognosis were evaluated.The median follow-up time was 22.5 (12-35) months. One patient with high-grade muscle-invasive bladder cancer (T2) received mTURBT, albumin-bound paclitaxel and durvalumab combined therapy for 3 cycles, concurrent radiotherapy, and immune maintenance therapy for 18 months, and the tumor recurrence was found. The pathology was high-grade urothelial carcinoma. Salvage radical cystectomy combined with pelvic lymph node dissection is recommended. The remaining 7 patients were regularly reexamined, and no recurrence or metastasis was found.The 2-year progression-free survival rate was 80%, and the success rate of bladder preservation was 87.5%(7/8). Treatment-related adverse reactions were resolved by symptomatic treatment, and patients' compliance and tolerance were acceptable.The "quadri-combination" bladder-preserving therapy is feasible and well tolerated, but further studies are needed.

Long-term follow-up of sequential intravesical gemcitabine and docetaxel salvage therapy for non-muscle invasive bladder cancer.

Intravesical gemcitabine and docetaxel (Gem/Doce) has been established as a safe and efficacious salvage treatment for recurrent NMIBC since 2015. Despite widespread adoption of this regimen, long-term outcomes have not been described. We report our experience with intravesical Gem/Doce following BCG failure in a large cohort of patients with extended follow-up. We retrospectively identified 97 patients at our institution treated with Gem/Doce for high-risk NMIBC after BCG failure between 2009 and 2017. Patients received six weekly intravesical Gem/Doce instillations. Monthly maintenance for 2 years was initiated if disease free at first follow-up. Outcomes included recurrence-free survival (RFS), high-grade recurrence-free survival (HG-RFS), progression-free survival (PFS), cystectomy-free survival (CFS), cancer-specific survival (CSS), and overall survival (OS). Survival probabilities were estimated using the Kaplan-Meier method. Median follow-up was 49 months. Median age was 73 years, and 71% of the cohort had CIS containing disease. Thirty five percent of the cohort had BCG-unresponsive disease. Complete response at 3-month surveillance was 74% and median duration of response was 25 months. At 1, 2, and 5 years, HG-RFS was 60%, 50%, and 30%, respectively. HG-RFS was similar among BCG-unresponsive patients and the overall cohort. During follow-up, 20 patients underwent cystectomy and 15 patients experienced disease progression. Five-year PFS, CFS, CSS, and OS were 82%, 75%, 91%, and 64%, respectively. In this long-term analysis, intravesical Gem/Doce for high-risk NMIBC after BCG failure yielded a 75% 5-year bladder preservation rate and a 91% 5-year cancer-specific survival rate. Further prospective trials are warranted.

Benefit of whole-pelvis radiation for patients with muscle-invasive bladder cancer: An inverse probability treatment-weighted analysis.

449 Background: Pelvic lymph node irradiation is still under debate for patients with muscle-invasive bladder cancer (MIBC) planned for curative-intent radiation-based therapy (RT). A previous randomized trial suggested bladder-only (BO)-RT was effective in reducing RT-related toxicity, while associated with non-inferior oncological outcomes – bladder preservation rates, disease-free survival, and overall survival (OS) – compared to whole-pelvis (WP)-RT. In this study, we sought to evaluate the impact of the radiation volume (BO-RT vs. WP-RT) on main oncological outcomes in patients with MIBC. Methods: This nationwide study included patients with urothelial MIBC (cT2-4aN0-2M0) who underwent curative RT at 10 academic centers across Canada. Patients clinically staged with pelvic or abdominal wall invasion (cT4b) or enlarged lymph nodes beyond the common iliac bifurcation (cN3) before RT were excluded. Patients were divided into two groups based on the RT volume: WP-RT vs. BO-RT. Inverse probability of treatment weighting (IPTW) and absolute standardized differences (ASDs) were used to balance baseline covariates across treatment groups. Regression models were used to assess the impact of the RT volume on the rates of complete response (CR) to treatment, cancer-specific survival (CSS), and OS while adjusting for potential confounding variables in the weighted cohorts. Results: A total of 599 patients were analyzed, out of whom 369 (61.6%) underwent WP-RT. Patients in the WP-RT group were younger (mean age 73.2 vs. 77.4; ASD 0.41), and more likely to have an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-1 (82.1% vs. 73.5%; ASD 0.21), clinical node-positive disease (12.5% vs. 2.2%; ASD 0.40), and lymphovascular invasion (26.3% vs. 16.1%; ASD 0.25), compared to BO-RT. In addition, WP-RT patients were more commonly treated with neoadjuvant chemotherapy (20.9% vs. 10.4%; ASD 0.29) and concurrent chemotherapy (76.7% vs. 56.5%; ASD 0.44), compared to BO-RT. In the IPTW cohort, age, gender, ECOG PS, clinical staging, the proportion of patients with carcinoma in situ, lymphovascular invasion, variant urothelial histologies, hydronephrosis, and whose tumours were completely resected before RT, treated with NAC, and treated with concurrent chemotherapy were well balanced across groups (all ASDs &lt; 0.10). In multivariable analysis, WP-RT did not impact CR rates post-RT (OR 1.14; p=0.526) but was associated with both CSS (HR 0.66; p=0.016) and OS (HR 0.68; p=0.002), independently of other prognostic factors (Table). Conclusions: Our study demonstrated a significant survival benefit with the use of WP-RT compared to BO-RT in patients with MIBC treated with curative intent. Additional randomized controlled trials are needed to confirm our findings.

Preliminary results from a phase II study of tislelizumab combined with radiotherapy as bladder-preserving treatment for patients with high-risk non-muscle-invasive bladder cancer (HR NMIBC) unresponsive to bacillus Calmette-Guerin (BCG).

510 Background: Radical cystectomy (RC) was recommended to patients (pts) with HR NMIBC BCG-unresponsive papillary tumors. Clinical unmet need was to explore non-surgical treatment options for pts who were ineligible for or refused RC. Our study aimed to evaluate the efficacy and safety of tislelizumab combined with radiotherapy as bladder-preserving treatment for pts with HR NMIBC unresponsive to BCG. Methods: This open-label, single arm phase II study enrolled pts with HR NMIBC BCG-unresponsive papillary tumors (high-grade Ta or T1 tumors without carcinoma in situ). The papillary tumors should be removed all visible lesions by transurethral resection of bladder tumor (TURBT). Within 2 weeks after TURBT, eligible pts received tislelizumab 200 mg in day 1 (D1), every 21 days for eight cycles and a total radiotherapy dose of 60-66 GY in 30-33 fractions over seven weeks. The primary end point was disease-free survival (DFS) rate at 12 months (defined as no reappearance of high grade or T1 tumors or clinical stage development after the therapy). Secondary end points were bladder-preservation rate, OS and safety. Our study anticipated a DFS rate at 12 months was 45% and the study would enroll 32 pts to meet the primary endpoint. Results: By Sep. 2022, 14 eligible pts were enrolled. Ten pts have completed therapy and were analyzed (male 90.0%; median age 58 years (31-79); pure TCC 100%; median tumor size 1.0 cm (0.5-2.0); 40% multiple papillary tumours; median eGFR, 91.1 mL/(min•1.73m2) (46.1-115.5); high-grade Ta 40.0%, T1 60.0%; median of 11 previous BCG instillations (9-19)). Median follow-up was 20.3 months (9.9-28.1), the median number of tislelizumab cycles was 8 (2-8) and radiotherapy doses was 60 GY (60-66) in 30 fractions. The DFS rate at 12 month was 80.0% (95%CI, 67.4%-92.6%), at 24 month was 60.0% (95%CI, 40.3%-79.7%). Two pts showed reappearance of high-grade Ta and received TURBT, one patient showed stage development from T1N0M0 to M1 disease and received systemic treatment. The bladder-preservation rate at 24 months was 100% (95%CI, 100%-100%). The OS rate at 24 months was 100% (95%CI, 100%-100%). Treatment related adverse events (TRAEs) of any grade were rash (40.0%), neutropenia (10.0%), hyperthyroidism (10.0%), AST/ALT increased (10.0%) and hyperglycaemia (10.0%). 5 pts experienced immune related AEs, including rash (n=4, G1-2), hyperthyroidism (n=1, G2), hyperglycaemia (n=1, G3) and AST/ALT increased (n=1, G3). Conclusions: Our preliminary results supported the use of tislelizumab combined with radiotherapy as a promising bladder-preserving therapy for pts with BCG-unresponsive HR NMIBC who were ineligible for or refused RC. Clinical trial information: ChiCTR2000035275 .

Detailed functional results after bladder-preserving surgery and high-dose-rate brachytherapy in pediatric bladder/prostate rhabdomyosarcoma

PurposeIn pediatric bladder/prostate-rhabdomyosarcoma, the rate of bladder preservation after neoadjuvant chemotherapy is high, with an excellent oncological outcome. Information about functional urological long-term outcomes is rare.MethodsData of all patients who had undergone bladder-preserving surgery with or without brachytherapy at our institution between 2009 and 2020 were analyzed retrospectively. Detailed urological function was assessed focusing on age-related continence, bladder capacity and urodynamic findings.ResultsWe identified 40 patients, median age at surgery of 27 months (range 9–191), and 32 patients additionally received postoperative high-dose-rate brachytherapy. The median follow-up was 32.5 months (range 6–125). The bladder capacity increased from median 66.7% (21.1–180) of expected bladder capacity related to age 3 months after surgery to 87.4% (58.1–181.8) 9 months after surgery. In the group of aged > 6-year-old, continence was 94% (83% with brachytherapy, 100% without brachytherapy). Erectile function was normal in 92% (90% with brachytherapy, 100% without brachytherapy). Bladder capacity was more than 65% expected bladder capacity related to age in 70% (60% with brachytherapy, 86% without brachytherapy). 65% of all patients need neither anticholinergic drugs nor low-dose antibiotics (63% with brachytherapy, 71% without brachytherapy).ConclusionsBladder preservation with good functional outcome can be achieved in localized bladder/prostate-rhabdomyosarcoma. In selected cases, supportive brachytherapy additionally contributes to an improvement in the oncological outcome with calculable risks for bladder and erectile function. Careful urological aftercare should be a fixed priority after oncological follow-ups.

Abstract 4058: Second generation imidazolium compounds as tumor-specific intravesical therapeutic agents for non-muscle invasive bladder cancer

Abstract Introduction: Intravesical therapy is critical in management of high-risk non-muscle invasive bladder cancer. The most effective intravesical therapy, BCG, has an ongoing shortage, while other second line therapies are not very effective, leaving radical cystectomy (RC) as the most effective option for cancer control. However, RC is a morbid, life-altering, and expensive procedure. Unfortunately, high-grade superficial disease is associated with cancer-specific mortality in 1/3 of the patients. Improved second line therapies or development of a BCG alternative would increase the rate of bladder preservation and survival, especially in light of the recurrent BCG shortages which have plagued bladder cancer patients. We earlier demonstrated that our first-generation imidazolium compounds are effective exfoliants that induce apoptosis via mitochondrial pathway and had potential to be used as intravesical therapy for bladder cancer. In this study, we developed and investigated second generation imidazolium compounds that have selective toxicity towards tumor tissues. We also investigated the mitochondrial target(s) of these imidazolium compounds. Methods: Second generation imidazolium compounds were screened for their toxicity against various bladder cancer cell lines using CellTiter-Glo and colony forming assay. Apoptosis induction was confirmed using western blot and propidium-iodide incorporation analysis. In vitro toxicity comparison between BBN-tumor organoids and normal organoids was performed using confocal microscopy. In vivo toxicity of these compounds was studied in normal mice. For candidate target identification, mitochondria from cells grown in SILAC heavy/light media were treated with biotinylated imidazolium compound or a mixture of biotinylated compound plus TPP1 (a first-generation imidazolium compound). Lysates were subjected to streptavidin pull down followed by LC-MS/MS proteomics analysis. Shortlisted target candidates were knocked down using siRNA followed by imidazolium treatment to assess their candidacy as the imidazolium target. Results: All second-generation imidazolium compounds had significantly higher toxicity to bladder cancer cell lines compared to first generation compounds. Compounds IS154 and IS155 were shown to be cancer selective. These two compounds showed no change in histopathology of murine bladder urothelium 24 h after intravesical instillation. Proteomics data from SILAC experiments prioritized three possible targets of the imidazolium compounds which are currently being explored. Conclusions: Second generation imidazolium compounds are tumor-specific and highly potent compounds that are worthy of further study as an intravesical agent for the treatment of high grade superficial bladder cancer. Citation Format: Uttam Satyal, David Weader, Henkel Valentine, Michael Stromyer, Wiley J. Youngs, Philip H. Abbosh. Second generation imidazolium compounds as tumor-specific intravesical therapeutic agents for non-muscle invasive bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4058.

Efficacy of hyperthermic-intra-vesical chemotherapy in patients with BCG-refractory nonmuscle-invasive bladder cancer.

4592 Background: In Bacillus Calmette-Guérin (BCG) refractory non-muscle-invasive bladder cancer (NMIBC), radical cystectomy is the standard of care. For patients unwilling or unable to undergo cystectomy, alternative intravesical therapies are currently being investigated to minimize the risk of recurrence and progression. Chemohyperthermia by HIVEC (Hyperthermic-Intra-Vesical Chemotherapy) is a therapeutic option in BCG-refractory patients. The objective of our study was to evaluate the 2-year oncological results of HIVEC in BCG-refractory patients. Methods: Between June 2016 and September 2021, patients treated with HIVEC (6 weekly instillations) for BCG-refractory NMIBC were prospectively included in our study. These patients had a theoretical indication for cystectomy but were ineligible for surgery or refused it. The primary endpoint was 1-year recurrence-free survival (RFS) rate. Secondary endpoints were 6-month complete response rate for Cis, 1-year overall and cancer-specific survival rates and bladder preservation rate. Results: Seventy patients, mean age 70 [42-89] years, were treated consecutively. After a mean follow-up of 20.9 months, 32 patients recurred (mean time of 10.6 months) and 7 patients finally had a cystectomy. The recurrence-free survival rate was 53.1% at 1 year and 20.5% at 2 years. Six patients progressed to a muscle-invasive disease, after a mean delay of 6.7 months. Four of them experienced metastatic progression and died from bladder cancer. Cancer-specific and overall survival rates were 95.1% and 92.9% at 1 year, and 87.5% and 77.8% at 2 years. The bladder preservation rate was 90%. For patients with Cis (34% of the entire series), the 6-month complete response rate was 75%. The presence of Cis was not a predictive factor of response to HIVEC. Tolerance was excellent with 38.2% grade 1-2 adverse events and no grade 3-4 adverse events. Conclusions: Chemohyperthermia using the HIVEC device achieved a RFS rate of 53.1% at 1 year and enabled a bladder preservation rate of 90%. While cystectomy remains the standard of care, HIVEC may be discussed cautiously for patients who are not eligible for surgery and well informed of the risk of progression to muscle-invasive disease.

Efficacy of chemohyperthermia (HIVEC) in patients with high-risk nonmuscle invasive bladder cancer (NMIBC) who fail BCG therapy.

456 Background: To evaluate Hyperthermic Intra-Vesical Chemotherapy (HIVEC) efficacy regarding 1-year disease-free survival (DFS) rate and bladder preservation rate in patients with high-risk Non-Muscle Invasive Bladder Cancer (NMIBC) who fail BCG therapy or are contraindicated to BCG. Methods: Between June 2016 and October 2019, patients treated with HIVEC for high-risk NMIBC who failed BCG (Fail-BCG) or BCG-naive if BCG contraindicated (N-BCG) have been included in our study. These patients had a theoretical indication for cystectomy but were ineligible for surgery or refused it. Results: Fifty-three patients, median age 72 [39-93] years, were included (n = 29 Fail-BCG and n = 24 N-BCG). The median follow-up was 18 months. The bladder preservation rate was 92.4%. The RFS rate at 12 months was 60.5%. The RFS rate at 12 months for N-BCG and Fail-BCG groups was respectively 70% and 52.2%. Three patients progressed to muscle-invasive disease, all in the Fail-BCG group and all in the very high-risk EORTC group. Two of them experienced metastatic progression and died from bladder cancer. Conclusions: Chemohyperthermia using HIVEC device achieved a RFS rate of 60% at 1 year and enabled a bladder preservation rate of 92%. Given the low risk of progression in the N-BCG group, HIVEC could be a good alternative. Conversely, for patients with very high-risk tumors that fail BCG, cystectomy should remain the standard of care and HIVEC may be discussed cautiously for patients who are not eligible for surgery and well informed of the risk of progression to muscle-invasive disease.

A phase II trial of risk enabled therapy after initiating neoadjuvant chemotherapy for bladder cancer (RETAIN BLADDER): Interim analysis.

397 Background: Cisplatin-based neoadjuvant chemotherapy (NAC) followed by cystectomy (Cx) or chemoradiation (CRT) is the standard of care for urothelial carcinoma (UC) pts with muscle invasive bladder cancer (MIBC). Both Cx and CRT have potential short and long-term toxicity and QOL implications. Mutations in DNA damage repair/response genes are associated with pathologic downstaging after NAC. Methods: We conducted a phase II, multi-institutional clinical trial (NCT02710734) to evaluate a risk-adapted approach to treatment of MIBC. Pts with cT2-T3N0M0 UC of the bladder, ECOG PS 0-1 and CrCl≥50 mL/min, underwent NAC with accelerated methotrexate, vinblastine, doxorubicin, and cisplatin (AMVAC). Pre-NAC TURBT specimens were sequenced (Caris Life Sciences) for mutations (pathogenic or VUS) in ATM, ERCC2, FANCC or RB1. Pts with at least one mutation and no clinical evidence of disease by restaging TUR and imaging post-NAC began pre-defined active surveillance (AS). Remaining pts underwent bladder-directed therapy: intravesical therapy ( &lt; cT2 post-NAC), CRT or Cx. The primary endpoint was metastasis-free survival (MFS) at 2 years which is not mature. We herein report key interim results of clinically-meaningful intermediate endpoints. Results: Seventy-one (ITT) pts were enrolled over 33 months at four academic centers. Median age was 70 years (47-83), 74% were male, 92% Caucasian, 81% ECOG PS 0 and 79% cT2. 90% completed 3 cycles of NAC and with 17% grade 3-4 TRAEs and one death during AMVAC. At the time of data cut-off (September 11, 2020), for the ITT pts, 32 pts have had a Cx, 5 underwent CRT and 7 underwent intravesical therapy, at some point during the trial. Thirty-three pts (46%) had a mutation of interest and 28 pts (39%) started AS (2 of the 28 pts on AS did not have a mutation but elected to start AS after achieving cT0 post AMVAC). 76% of those with a mutation were cT0 at post-NAC TURBT. With a median follow-up of 14.9 mo (range: 3.1-35.3 mo), 14 AS pts recurred (50%). Of the 14 recurrences, 2 recurred with locally advanced or metastatic disease and have died, 5 had MIBC with one eventual metastatic recurrence, and 7 had NMIBC. Six (14%) non-AS pts have died. Out of the 40 pts who did not go to upfront Cx [AS (N = 28), CRT (N = 5), intravesical tx (N = 7)], 3 (7.5%) (all in the AS group) went on to Cx later. The bladder preservation rate is 55% for ITT pts and 89% for the AS group. In the AS cohort, mutations were seen in RB1 (50%), ATM (42%), ERCC2 (31%), FANCC (4%) with lowest rate for recurrence in ERCC2 (25% recurrence) vs RB1 (62% recurrence). Conclusions: Interim results of a phase II trial of risk enabled therapy utilizing a selection of clinical and genomic factors in pts with cT2-T3 MIBC demonstrates a 50% rate of any UC recurrence and a 11% rate of locally advanced/metastatic disease in the AS group. 89% of AS pts have retained their bladder. Follow-up continues for the primary endpoint of 2-year MFS. Clinical trial information: NCT02710734.

Neoadjuvant chemoradiotherapy for patients with unresectable radically locally advanced colon cancer: a potential improvement to overall survival and decrease to multivisceral resection

BackgroundThe management of unresectable locally advanced colon cancer (LACC) remains controversial, as resection is not feasible. The goal of this study was to evaluate the treatment outcomes and toxicity of neoadjuvant chemoradiotherapy (NACRT) followed with surgery and adjuvant chemotherapy in patients with unresectable radically LACC.MethodsWe included patients who were diagnosed at our institution, 2010–2018. The neoadjuvant regimen consisted of radiotherapy and capecitabine/ 5-fluorouracil-based chemotherapy.ResultsOne hundred patients were identified. The median follow-up time was 32 months. The R0 resection rate, adjusted nonmultivisceral resection rate and bladder preservation rate were 83.0, 43.0 and 83.3%, respectively. The pCR and clinical-downstaging rates were 18, and 81.0%%, respectively. The 3-year PFS and OS rates for all patients were 68.6 and 82.1%, respectively. Seventeen patients developed grade 3–4 myelosuppression, which was the most common adverse event observed after NACRT. Tumor perforation occurred in 3 patients during NACRT. The incidence of grade 3–4 surgery-related complications was 7.0%. Postoperative anastomotic leakage was observed in 3 patients.ConclusionsNACRT followed by surgery was feasible and safe for selected patients with LACC, and can be used as a conversion treatment to achieve satisfactory downstaging, long-term survival and quality of life, with acceptable toxicities.

Efficacy of HIVEC in patients with high-risk non-muscle invasive bladder cancer who are contraindicated to BCG and in patients who fail BCG therapy

Purpose To evaluate Hyperthermic-Intra-Vesical Chemotherapy (HIVEC) efficacy regarding 1-year disease-free survival (RFS) rate and bladder preservation rate in patients with High-risk Non-Muscle Invasive Bladder Cancer (NMIBC) who fail BCG therapy or are contraindicated to BCG. Methods Between June 2016 and October 2019, patients treated with HIVEC for mostly high-risk NMIBC who failed BCG or BCG-naive if BCG contraindicated have been included in our study. These patients had a theoretical indication for cystectomy but were ineligible for surgery or refused it. Results Fifty-three patients, median age 72 [39–93] years, were included in this study (n = 29 BCG-failure and n = 24 BCG-naive). The median follow-up was 18 months. The bladder preservation rate was 92.4%. The 12 months-RFS rate was 60.5%. The RFS rates for BCG-naive and BCG-failure groups were respectively 70% and 52.2% at 12 months. Three patients progressed to muscle infiltration, all in the BCG-failure group and all in the very high-risk EORTC group. Two of them developed metastatic disease and died from bladder cancer. Conclusion Chemohyperthermia using HIVEC achieved a RFS rate of 60% at 1 year and enabled a bladder preservation rate of 92%. Given the low risk of progression in the BCG-naive group, HIVEC could be a good alternative. Conversely, for patients with very high-risk tumors that fail BCG, cystectomy should remain the standard of care and HIVEC may be discussed cautiously for patients who are not eligible for surgery and well informed of the risk of progression to muscle-invasive disease.

The Role of Reconstructive Surgery and Brachytherapy in Pediatric Bladder/Prostate Rhabdomyosarcoma.

The surgical approach to localized bladder/prostate rhabdomyosarcoma in children may change due to a new radiotherapeutic modality. We assessed the impact of brachytherapy following surgery for local tumor control, and report surgical techniques and outcomes. We retrospectively analyzed the records of all children who underwent surgery for bladder/prostate rhabdomyosarcoma, including tumor relapse, at our institution from 2009 onward. A total of 38 patients with a median age of 29 months (range 10 to 134) met inclusion criteria. Five-year overall survival was 92.8% (95% CI 72.9 to 98.1), and event-free survival at a median followup of 12 months (range 3 to 111) was 73.7% (95% CI 53.4 to 86.2). Three treatment groups were defined, ie bladder preserving surgery combined with brachytherapy, bladder preserving surgery alone and cystectomy. Five-year event-free survival rates for the 3 groups were 85.6% (95% CI 61.2 to 95.2), 66.7% (95% CI 27.2 to 88.2) and 50% (95% CI 5.8 to 84.5), respectively. Bladder preserving surgery was performed in 33 patients (87%), of whom 23 (70%) also underwent brachytherapy, while cystectomy was performed in 5 (13%). Reconstructive procedures varied depending on tumor location and spread. Combining brachytherapy with surgery results in a high bladder preservation rate and improves event-free survival compared to surgery alone in children with bladder/prostate rhabdomyosarcoma. The combination is also effective in treating local tumor relapse, and is associated with less extensive reconstructive procedures due to exclusion of tumors of unfavorable size and location for brachytherapy.

PD51-07 ONCOLOGIC AND FUNCTIONAL EFFECTIVENESS OF NEOADJUVANT CHEMOTHERAPY FOLLOWED BY EITHER BLADDER-SPARING SURGERY PLUS CONCURRENT CHEMORADIOTHERAPY OR CYSTECTOMY FOR MUSCLE-INVASIVE BLADDER CANCER

INTRODUCTION AND OBJECTIVE: Previous researches indicated Neoadjuvant Chemotherapy (NAC) achieved optimistic tumor degrading and bladder preservation rates in muscle-invasive bladder cancer (MIBC). However, maximum Transurethral Resection of Bladder Tumor (TURBT) was mostly performed before NAC which might impact oncologic effect of NAC. Our aim was to assess the real effect of NAC for MIBC before TURBT, then bladder preservation rate and quality of life. METHODS: Patients with clinical T2-4N0M0 bladder cancer confirmed by imagings and biopsy, were enrolled from September 2015 to September 2018. 3 or 4 courses of NAC were performed with Gemcitabine/Cisplatin (GC) regimen. Imagings, urine cytology and TURBT were underwent to assess NAC effect. Responders received bladder-sparing treatments including chemoradiotherapy or partial cystectomy followed by Bacillus Calmette-Guerin (BCG) instillation, but salvage cystectomy if recurrence. Others received radical cystectomy. The endpoints included overall survival (OS), bladder preservation rates and life quality. RESULTS: 59 patients (53 men & 6 women) were enrolled with a median age of 63 years. Numbers of patients at each clinical stage were: cT2 15, cT3 39, cT4 5. All pathologies of biopsy were urothelial carcinoma. The complete response (CR) rate of NAC was 10.2% (6/59) and an additional 52.5% (31/59) experienced a partial response (PR), for an overall response rate (ORR) of 62.7%. Of these 37 cases, 94.6% received combined-modality treatments of bladder preservation including TURBT plus chemoradiotherapy (42.4%), TURBT plus BCG (6.8%), TURBT (3.4%), and partial cystectomy plus pelvic lymphadenectomy (6.8%). With a median follow-up of 28.3 months, the 3-year OS was 71.2%. 59.3% (35/59) successfully preserved bladder and the OS was 88.0%, besides relapse-free survival (RFS) was 70.5%. In SF-36 questionnaires, patients had favorable scores of total physical (59 ± 6.11) and tmental (55 ± 5.44) health. As for preserved bladder function, the results of OABSS were satisfied. CONCLUSIONS: NAC had a good efficacy in MIBC. Responders can choose combined-modality treatments for bladder preservation, resulting in satisfied bladder-sparing rate, fair prognosis and quality of life. Source of Funding: 2015 Beijing Hope Run Special Fund of China Cancer Research Foundation

Prospective evaluation of definitive chemoradiotherapy with volumetric modulated arc therapy in patients with muscle invasive carcinoma of urinary bladder.

IntroductionConcurrent chemoradiotherapy (CTRT) remains one of the treatment options in patients with muscle invasive bladder cancer (MIBC) unwilling/unsuitable for radical surgery. We evaluated the role of volumetric modulated arc therapy (VMAT) in MIBC patients treated with definitive CTRT.Material and methods25 patients of histologically proven transitional cell MIBC (T2–T4a, N0, M0) unwilling/unsuitable for radical surgery (after maximal transurethral resection of bladder tumour) were recruited in this prospective study. Primary clinical target volume (CTV) consisted of the gross tumour and whole bladder. Primary planning target volume (PTV) and nodal PTV were prescribed 60 Gy and 54 Gy (both in 30 fractions). Concurrent chemotherapy was cisplatin (40 mg/m2) weekly. Acute toxicities were assessed as per Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Survival estimates were done from the date of registration using the Kaplan-Meier method.ResultsMedian age was 70 years (37–80 years). Median overall treatment time was 45 days (44–51). Median number of chemotherapy cycles was 5 (range 3–6). 5 (20%) and 4 (16%) patients respectively suffered from acute grade ≥ 2 gastrointestinal and grade ≥ 2 genitourinary toxicities during treatment. One patient each had grade 3 anaemia and neutropenia. At a median follow-up of 34 months (10–45 months), 3-year progression-free survival and overall survival were 65.6% and 81.2% respectively. 3-year distant metastasis-free survival was 90.5%. Bladder preservation rate at 3 years was 68%.ConclusionsDefinitive CTRT with VMAT is well tolerated in patients with MIBC unsuitable for surgery and yields decent survival and bladder preservation outcome.