Current Trends and Challenges of Microbiome Research in Bladder Cancer.

PURPOSE OF THE REVIEW: Microbiome research has provided valuable insights into the associations between microbial communities and bladder cancer. However, this field faces significant challenges that hinder the interpretation, generalization, and translation of findings into clinical practice. This review aims to elucidate these challenges and highlight the importance of addressing them for the advancement of microbiome research in bladder cancer. RECENT FINDINGS: Recent findings underscore the complexities involved in microbiome research, particularly in the context of bladder cancer. Challenges include low microbial biomass in urine samples, potential contamination issues during collection and processing, variability in sequencing methods and primer selection, and the difficulty of establishing causality between microbiota and bladder cancer. Studies have shown the impact of sample storage conditions and DNA isolation kits on microbiome analysis, emphasizing the need for standardization. Additionally, variations in urine collection methods can introduce contamination and affect results. The choice of 16S rRNA gene amplicon sequencing or shotgun metagenomic sequencing introduces technical challenges, including primer selection and sequencing read length. Establishing causality between the microbiota and bladder cancer requires experimental methods like fecal microbiota transplantation and human microbiota-associated murine models, which face their own set of challenges. Translating microbiome research into therapeutic applications is hindered by methodological variability, incomplete understanding of bioactive molecules, imperfect animal models, and the inherent heterogeneity of microbiome communities among individuals. Microbiome research in bladder cancer presents significant challenges stemming from technical and conceptual complexities. Addressing these challenges through standardization, improved experimental models, and advanced analytical approaches is essential for advancing our understanding of the microbiome's role in bladder cancer and its potential clinical applications. Achieving this goal can lead to improved patient outcomes and novel therapeutic strategies in the future.

Multidisciplinary management of sexual and gender minorities with bladder cancer.

Bladder cancer, a common urologic malignancy, has poor morbidity and mortality in sexual and gender minority (SGM) individuals, stemming from higher risk, poor access to care and lack of quality cancer care. To begin addressing this disparity, this review offers key considerations for evaluation, diagnosis and treatment of SGM individuals with bladder cancer. In addition to thorough medical and surgical history, initial evaluation should include discussion of patient goals for sexual function and organ preservation, as well as an evaluation of sexual function. Prior gender affirming surgery and patient specific sexual function goals will impact diagnosis and treatment approaches, including surgical and radiation therapy. Throughout care for SGM individuals with bladder cancer, it is critical to acknowledge the systemic discrimination that may be experienced by these individuals and approach conversations with sensitivity and humility and incorporate mental and social support as appropriate.

Population Estimates of Ovarian Cancer Risk in a Cohort of Patients with Bladder Cancer.

BACKGROUND AND OBJECTIVE: The rationale for oophorectomy during female cystectomy is not adequately supported. The co-occurrence and timing of bladder cancer (BC) and ovarian cancer (OC) in females harboring OC germline mutations remain unclear. Our objective was to determine the frequency and temporal occurrence of OC germline variants among females with BC. METHODS: We used genetic and phenotypic data from the UK Biobank (UKB). The study cohort was defined using ICD-10/ICD-9 codes for BC and further stratified to identify 1347 females. Analysis was restricted to variants with high/moderate impact for initial regression. ClinVar was used to interpret pathogenicity. Pathogenic/likely pathogenic (P/LP) variants were assessed by age of presentation, family history, and concomitant malignancies. Statistical analysis was performed using UKB DNAnexus JupyterLab and RStudio. KEY FINDINGS AND LIMITATIONS: Some 3.4% of the patients had at least one of 15 variants for OC. CHEK2 and PALB2 mutations represented the highest ratio of overall/pathogenic variants (15.8% and 6.6%). Although females with P/LP OC mutations had a higher risk of OC, diagnosis of OC preceded BC by 11.3 yr (±12.5 yr) in the group with mutations and by 15.6 yr (±11.3 yr) in the group without mutations. The group with P/LP variants had higher rates of maternal (14.63% vs 8.12%; p = 0.04) and sibling (9.76% vs 3.98%; p = 0.02) breast cancer and of maternal colon cancer (9.76% vs 4.21%), and lower maternal life expectancy (75.34 vs 68.15 yr; p = 0.0014). UKB provides limited staging/treatment history and its exome sequencing platform may miss variants or provide insufficient coverage for genotyping. CONCLUSIONS AND CLINICAL IMPLICATIONS: This study provides evidence against routine oophorectomy for reducing OC risk in females with BC. The results highlight that the development of OC occurred 11 yr before diagnosis of BC for patients with OC mutations and 15 yr before diagnosis of BC for patients without OC mutations. PATIENT SUMMARY: Although removal of the ovaries in women with bladder cancer is common, no studies have shown that this strategy has a benefit. Our study of women diagnosed with bladder cancer who had genetic mutations associated with ovarian cancer shows that their risk of developing ovarian cancer after bladder cancer is low. These findings provide evidence against removal of the ovaries when the bladder is being removed as treatment for bladder cancer.

Financial Distress in Genitourinary Cancer: Insights From CDC National Health Interview Survey.

PURPOSE: This study leverages CDC National Health Interview Survey data to examine Financial Distress (FD) among genitourinary (GU) cancer survivors, specifically prostate cancer (PC), kidney cancer (KC), and bladder cancer (BC). It investigates the economic impacts faced by these patients, especially in relation to disparities in insurance coverage and its effects on material, psychological, and behavioral aspects of FD. METHODS: We retrospectively analyzed responses from GU cancer survivors, stratifying by cancer status and age (18-64 years, ≥65 years). Medical financial hardship was divided into three domains: material, psychological, and behavioral. Associations between cancer history, hardship, and clinical factors were assessed using generalized ordinal logistic regressions. RESULTS: Significant health care access disparities were found, particularly for mental health services, with 25% of younger BC survivors and 4.7% of younger KC survivors reporting affordability issues, in contrast to 2.7% of noncancer individuals. Dental care was also problematic, with higher avoidance rates among younger BC (27%) and KC (15%) survivors compared with the general population. Surprisingly, noncancer individuals reported more difficulty in affording prescriptions than BC survivors across both age groups. PC survivors, however, showed lower FD across all domains versus noncancer controls, indicating fewer concerns about medical bills and a lesser tendency to forgo care. CONCLUSION: The study underscores significant gaps in the financial support system for GU cancer survivors, with urgent needs in mental and dental health care access. Policy interventions, including comprehensive insurance reforms, are imperative to alleviate the financial burdens on these individuals.

Identification and Validation of Prognostic Model for Tumor Microenvironment-Associated Genes in Bladder Cancer Based on Single-Cell RNA Sequencing Data Sets.

PURPOSE: The purpose of this study was to elucidate the relationship between the tumor microenvironment (TME) and cellular diversity in bladder cancer (BLCA) progression, leveraging single-cell RNA sequencing (scRNA-seq) data to identify potential prognostic biomarkers and construct a prognostic model for BLCA. METHODS: We analyzed scRNA-seq data of normal and tumor bladder cells from the Gene Expression Omnibus (GEO) database to uncover crucial markers within the bladder TME. The study compared gene expression in normal versus tumor bladder cells, identifying differentially expressed genes. These genes were subsequently assessed for their prognostic significance using patient follow-up data from The Cancer Genome Atlas. Prognostic models were constructed using Least Absolute Shrinkage and Selection Operator and multivariate Cox regression analyses, focusing on eight genes of interest. The predictive performance of the model was also tested against additional GEO data sets (GSE31684, GSE13507, and GSE32894). RESULTS: The prognostic model demonstrated reliable prediction of patient outcomes. Validation through gene set enrichment analysis and immune cell infiltration assessment supported the model's efficacy. The results from both the univariate and multivariate analyses suggest that the risk score is an independent prognostic factor with a hazard ratio of 2.97 (95% CI, 2.28 to 3.9, P < .001). In the validation cohort, the AUC at 1, 2, and 3 years is 0.74, 0.74, and 0.72, respectively. CONCLUSION: Our findings proposed biomarkers with prognostic potential, laying the groundwork for future in vitro validation and therapeutic exploration. This contributes to a deeper understanding of the genes associated with bladder TME and may improve prognostic precision in BLCA management.

Role of Gut Microbiome in Neoadjuvant Chemotherapy Response in Urothelial Carcinoma: A Multi-institutional Prospective Cohort Evaluation.

Neoadjuvant chemotherapy (NAC) is linked with clinical advantages in urothelial carcinoma for patients with muscle-invasive bladder cancer (MIBC). Despite comprehensive research into the influence of tumor mutation expression profiles and clinicopathologic factors on chemotherapy response, the role of the gut microbiome (GM) in bladder cancer chemotherapy response remains poorly understood. This study examines the variance in the GM of patients with bladder cancer compared with healthy adults, and investigates GM compositional differences between patients who respond to chemotherapy versus those who exhibit residual disease.Our study reveals distinct clustering, effectively separating the bladder cancer and healthy cohorts. However, no significant differences were observed between chemotherapy responders and nonresponders within community subgroups. Machine learning models based on responder status outperformed clinical variables in predicting complete response (AUC 0.88 vs. AUC 0.50), although no single microbial species emerged as a fully reliable biomarker.The evaluation of short chain fatty acid (SCFA) concentration in blood and stool revealed no correlation with responder status. Still, SCFA analysis showed a higher abundance of Akkermansia (rs = 0.51, P = 0.017) and Clostridia (rs = 0.52, P = 0.018), which correlated with increased levels of detectable fecal isobutyric acid. Higher levels of fecal Lactobacillus (rs = 0.49, P = 0.02) and Enterobacteriaceae (rs = 0.52, P < 0.03) correlated with increased fecal propionic acid.In conclusion, our study constitutes the first large-scale, multicenter assessment of GM composition, suggesting the potential for a complex microbial signature to predict patients more likely to respond to NAC based on multiple taxa. SIGNIFICANCE: Our study highlights results that link the composition of the GM to the efficacy of NAC in MIBC. We discovered that patients with higher levels of Bacteroides experienced a worse response to NAC. This microbial signature shows promise as a superior predictor of treatment response over traditional clinical variables. Although preliminary, our findings advocate for larger, more detailed studies to validate these associations.

Urine Biopsy as Dynamic Biomarker to Enhance Clinical Staging of Bladder Cancer in Radical Cystectomy Candidates.

PURPOSE: There is significant interest in identifying complete responders to neoadjuvant chemotherapy (NAC) before radical cystectomy (RC) to potentially avoid removal of a pathologically benign bladder. However, clinical restaging after NAC is highly inaccurate. The objective of this study was to develop a next-generation sequencing-based molecular assay using urine to enhance clinical staging of patients with bladder cancer. METHODS: Urine samples from 20 and 44 patients with bladder cancer undergoing RC were prospectively collected for retrospective analysis for molecular correlate analysis from two clinical trials, respectively. The first cohort was used to benchmark the assay, and the second was used to determine the performance characteristics of the test as it correlates to responder status as measured by pathologic examination. RESULTS: First, to benchmark the assay, known mutations identified in the tissue (MT) of patients from the Accelerated Methotrexate, Vinblastine, Doxorubicin, Cisplatin trial (ClinicalTrials.gov identifier: NCT01611662, n = 16) and a cohort from University of California-San Francisco (n = 4) were cross referenced against mutation profiles from urine (MU). We then determined the correlation between MU persistence and residual disease in pre-RC urine samples from a second prospective clinical trial (The pT0 trial; ClinicalTrials.gov identifier: NCT02968732). Residual MU status correlated strongly with residual disease status (pT0 trial; n = 44; P = .0092) when MU from urine supernatant and urine pellet were assessed separately and analyzed in tandem. The sensitivity, specificity, PPV, and NPV were 91%, 50%, 86%, and 63% respectively, with an overall accuracy of 82% for this second cohort. CONCLUSION: MU are representative of MT and thus can be used to enhance clinical staging of urothelial carcinoma. Urine biopsy may be used as a reliable tool that can be further developed to identify complete response to NAC in anticipation of safe RC avoidance.

Cost of Care in Open Cystectomy Patients Across Time and Space: Does it matter?

BACKGROUND: Many variables may affect the cost of open radical cystectomy (RC) care, including surgical approach, diversion type, patient comorbidities, and postoperative complications. OBJECTIVE: To determine factors associated with changes in cost of care following open radical cystectomy (ORC) for bladder cancer using the National Inpatient Sample (NIS). METHODS: Patients in the NIS with a diagnosis of bladder cancer who underwent ORC with ileal conduit from 2012-2017 using ICD-9-CM and ICD-10-CM codes were identified. Baseline demographics including age, race, region, postoperative complications, and length of stay were obtained. Univariable and multivariable logistic regression were used to identify factors associated with cost variation including demographics, clinical characteristics, surgical factors, and discharge quarter (Q1-Q4). RESULTS: 5,189 patients were included in the analysis, with 4,379 at urban teaching hospitals. On multivariable regression analysis, female sex [$1,734 ($1,024-2,444) p < 0.001)], a greater Elixhauser comorbidity score [$93 ($62-124), p < 0.001], presence of any inpatient complication [$1,531 ($894-2,168), p < 0.001], and greater length of stay [$1,665 ($1,536-1,793), p < 0.001] were associated with a greater cost of hospitalization. Discharge in Q3 (July to September) relative to Q2 (April to June) was associated with a higher cost [$1,113 ($292-1,933), p = 0.008. Trends were similar at urban non-teaching and rural hospitals, except discharge quarter was not associated with a significant change in cost. CONCLUSIONS: Significant differences in cost of ORC with ileal conduit exist with respect to patient sex, medical comorbidities, and discharge timing. These differences may relate to greater disease burden in female patients, patient complexity, and variation in postoperative care in academic programs.