The Impact of Histologic Subtypes on Clinical Outcomes After Radiation-Based Therapy for Muscle-Invasive Bladder Cancer.

PURPOSE: Outcomes of radiation-based therapy (RT) for muscle-invasive bladder cancer (MIBC) with histologic subtypes of urothelial cancer (HS-UC) are lacking. Our objective was to compare survival outcomes of pure urothelial carcinoma (PUC) to HS-UC after RT. MATERIALS AND METHODS: A multicenter retrospective study of 864 patients with MIBC who underwent curative-intent RT to the bladder for MIBC (clinical T2-T4aN0-2M0) between 2001 and 2018 was conducted. Regression models were used to test the association between HS-UC and complete response (CR) and survival outcomes after RT. RESULTS: In total, 122 patients (14%) had HS-UC. Seventy-five (61%) had HS-UC with squamous and/or glandular differentiation. A CR was confirmed in 69% of patients with PUC and 63% with HS-UC. There were 207 (28%) and 31 (25%) patients who died of metastatic bladder cancer in the PUC and HS-UC groups, respectively. There were 361 (49%) and 58 (48%) patients who died of any cause in the PUC and HS-UC groups, respectively. Survival outcomes were not statistically different between the groups. The HS-UC status was not associated with survival outcomes in multivariable Cox regression analyses. CONCLUSIONS: In our study, HS-UC responded to RT with no significant difference in CR and survival outcomes compared to PUC. The presence of HS-UC in MIBC does not seem to confer resistance to RT, and patients should not be withheld from bladder preservation therapy options. Due to low numbers, definitive conclusions cannot be drawn for particular histologic subtypes.

Atypical B cells promote cancer progression and poor response to Bacillus Calmette-Guérin in non-muscle invasive bladder cancer.

Poor response to Bacillus Calmette-Guérin (BCG) immunotherapy remains a major barrier in the management of patients with non-muscle invasive bladder cancer (NMIBC). Multiple factors are associated with poor outcomes, including biological aging and female sex. More recently, it has emerged that a B-cell infiltrated pre-treatment immune microenvironment of NMIBC tumors can influence the response to intra-vesically administered BCG. The mechanisms underlying the roles of B cells in NMIBC are poorly understood. Here, we show that B-cell dominant tertiary lymphoid structures (TLSs), a hallmark feature of the chronic mucosal immune response, are abundant and located close to the epithelial compartment in pre-treatment tumors from BCG non-responders. Digital spatial proteomic profiling of whole tumor sections from male and female patients with NMIBC who underwent treatment with intravesical BCG, revealed higher expression of immune exhaustion-associated proteins within the tumor-adjacent TLSs in both responders and non-responders. Chronic local inflammation, induced by the N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) carcinogen, led to TLS formation with recruitment and differentiation of the immunosuppressive atypical B-cell (ABC) subset within the bladder microenvironment, predominantly in aging female mice compared to their male counterparts. Depletion of ABCs simultaneous to BCG treatment delayed cancer progression in female mice. Our findings provide evidence indicating a role for ABCs in BCG response and will inform future development of therapies targeting the B cell-exhaustion axis.

Systemic versus localized Bacillus Calmette Guérin immunotherapy of bladder cancer promotes an anti-tumoral microenvironment: Novel role of trained immunity.

Treatment for higher-risk non-muscle invasive bladder cancer (NMIBC) involves intravesical immunotherapy with Bacillus Calmette Guérin (BCG); however, disease recurrence and progression occur frequently. Systemic immunity is critical for successful cancer immunotherapy; thus, recurrence of NMIBC may be due to suboptimal systemic activation of anti-tumor immunity after local immunotherapy. We previously reported that systemically acquired trained immunity (a form of innate immune memory) in circulating monocytes is associated with increased time-to-recurrence in patients with NMIBC treated with BCG. Herein, we used a mouse model of NMIBC to compare the effects of intravesical versus intravenous (systemic) BCG immunotherapy on the local and peripheral immune microenvironments. We also assessed whether BCG-induced trained immunity modulates anti-tumor immune responses. Compared with intravesical BCG, which led to a tumor-promoting immune microenvironment, intravenous BCG resulted in an anti-tumoral bladder microenvironment characterized by increased proportions of cytotoxic T lymphocytes (CTLs), and decreased proportions of myeloid-derived suppressor cells. Polarization toward anti-tumoral immunity occurred in draining lymph nodes, spleen, and bone marrow following intravenous versus intravesical BCG treatment. Pre-treatment with intravesical BCG was associated with increased rate of tumor growth compared with intravenous BCG pre-treatment. Trained immunity contributed to remodeling of the tumor immune microenvironment, as co-instillation of BCG-trained macrophages with ovalbumin-expressing bladder tumor cells increased the proportion of tumor-specific CTLs. Furthermore, BCG-trained dendritic cells exhibited enhanced antigen uptake and presentation and promoted CTL proliferation. Our data support the concept that systemic immune activation promotes anti-tumor responses, and that BCG-induced trained immunity is important in driving anti-tumor adaptive immunity.

Real-life benchmarking bladder cancer care: A population-based study.

INTRODUCTION: Radical cystectomy (RC) is a complex oncological surgical procedure and population studies of routine surgical care have suggested suboptimal results compared to high-volume centers of excellence. A previous Canadian bladder cancer quality-of-care consensus led to adoption of multiple key quality-of-care indicators, with associated benchmarks created using available evidence and expert opinion to inform and measure future performance. Herein, we report real-life benchmark performance for the management of muscle-invasive bladder cancer (MIBC) relative to expert opinion guidance. METHODS: This is a population-based, retrospective, cohort study that used the Ontario Cancer Registry (OCR) to identify all incident patients who underwent RC from 2009-2013. Electronic records of treatment from 1573 patients were linked to OCR; pathology records were obtained for all cases and reviewed by a team of trained data abstractors. The primary objective was to describe benchmarks for identified indicators, first as median values obtained across hospitals or providers, as well as a "pared-mean" approach to identify a benchmark population of "top performance," as defined as the best outcome accomplished for at least 10% of the population. RESULTS: Overall, performance in Ontario across all indicators fell short of expert opinion-determined benchmarks. Annual surgical volume by each surgeon performing a RC (benchmark >6, percent of institutions meeting benchmark=20%), percent of patients with MIBC referred preoperatively to medical oncology (MO; benchmark>90%, percent of institutions meeting benchmark=2%) and radiation oncology (RO; benchmark>50%, percent of institutions meeting benchmark=0%), time to cystectomy within six weeks of transurethral resection of bladder tumor (TURBT) in patients without neoadjuvant chemotherapy (benchmark <6 weeks, percent of institutions meeting benchmark=0%), percent of patients with adequate lymph node dissection (defined as >14 nodes, benchmark>85%, percent of institutions meeting benchmark=0%), percent of patients with positive margins post-RC (benchmark <10%, percent of institutions meeting benchmark=46%), and 90-day mortality (benchmark<5%, percent of institutions meeting benchmark=37%) fell considerably short. Simply evaluating benchmarks across the province as median performance significantly underestimated benchmarks that were possible by top-performing hospitals. CONCLUSIONS: Performance through most bladder cancer quality-of-care indicators fall short of benchmarks proposed by expert opinion. Different methodologies, such as a paredmean approach of top performers, may provide more realistic benchmarking.