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.

Artificial Intelligence-Based PTEN Loss Assessment as an Early Predictor of Prostate Cancer Metastasis After Surgery: A Multicenter Retrospective Study.

Phosphatase and tensin homolog (PTEN) loss is associated with adverse outcomes in prostate cancer and can be measured via immunohistochemistry. The purpose of the study was to establish the clinical application of an in-house developed artificial intelligence (AI) image analysis workflow for automated detection of PTEN loss on digital images for identifying patients at risk of early recurrence and metastasis. Postsurgical tissue microarray sections from the Canary Foundation (n = 1264) stained with anti-PTEN antibody were evaluated independently by pathologist conventional visual scoring (cPTEN) and an automated AI-based image analysis pipeline (AI-PTEN). The relationship of PTEN evaluation methods with cancer recurrence and metastasis was analyzed using multivariable Cox proportional hazard and decision curve models. Both cPTEN scoring by the pathologist and quantification of PTEN loss by AI (high-risk AI-qPTEN) were significantly associated with shorter metastasis-free survival (MFS) in univariable analysis (cPTEN hazard ratio [HR], 1.54; CI, 1.07-2.21; P = .019; AI-qPTEN HR, 2.55; CI, 1.83-3.56; P < .001). In multivariable analyses, AI-qPTEN showed a statistically significant association with shorter MFS (HR, 2.17; CI, 1.49-3.17; P < .001) and recurrence-free survival (HR, 1.36; CI, 1.06-1.75; P = .016) when adjusting for relevant postsurgical clinical nomogram (Cancer of the Prostate Risk Assessment [CAPRA] postsurgical score [CAPRA-S]), whereas cPTEN does not show a statistically significant association (HR, 1.33; CI, 0.89-2; P = .2 and HR, 1.26; CI, 0.99-1.62; P = .063, respectively) when adjusting for CAPRA-S risk stratification. More importantly, AI-qPTEN was associated with shorter MFS in patients with favorable pathological stage and negative surgical margins (HR, 2.72; CI, 1.46-5.06; P = .002). Workflow also demonstrated enhanced clinical utility in decision curve analysis, more accurately identifying men who might benefit from adjuvant therapy postsurgery. This study demonstrates the clinical value of an affordable and fully automated AI-powered PTEN assessment for evaluating the risk of developing metastasis or disease recurrence after radical prostatectomy. Adding the AI-qPTEN assessment workflow to clinical variables may affect postoperative surveillance or management options, particularly in low-risk patients.