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 clinicopathological factors on chemotherapy response, the role of the gut microbiome (GM) in bladder cancer(BC) chemotherapy response remains poorly understood. This study examines the variance in the gut microbiome(GM) of BC patients compared to 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 BC and healthy cohorts. However, no significant differences were observed between chemotherapy responders and non-responders 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, multi-center 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.

Decisional and prognostic impact of diagnostic ureteroscopy in high-risk upper tract urothelial carcinoma: A multi-institutional collaborative analysis (ROBUUST collaborative group).

BACKGROUND: Diagnostic ureteroscopy (URS) with or without biopsy remains a subject of contention in the management of upper tract urothelial carcinoma (UTUC), with varying recommendations across different guidelines. The study aims to analyse the decision-making and prognostic role of diagnostic ureteroscopy (URS) in high-risk UTUC patients undergoing curative surgery. MATERIALS AND METHODS: In this retrospective multi-institutional analysis of high-risk UTUC patients from the ROBUUST dataset, a comparison between patients who received or not preoperative URS and biopsy before curative surgery was carried out. Logistic regression analysis evaluated differences between patients receiving URS and its impact on treatment strategy. Survival analysis included 5-year recurrence-free survival (RFS), metastasis-free survival (MFS), cancer-specific survival (CSS) and overall survival (OS). After adjusting for high-risk prognostic group features, Cox proportional hazard model estimated significant predictors of time-to-event outcomes. RESULTS: Overall, 1,912 patients were included, 1,035 with preoperative URS and biopsy and 877 without. Median follow-up: 24 months. Robot-assisted radical nephroureterectomy was the most common procedure (55.1%), in both subgroups. The 5-year OS (P = 0.04) and CSS (P < 0.001) were significantly higher for patients undergoing URS. The 5-year RFS (P = 0.6), and MFS (P = 0.3) were comparable between the 2 groups. Preoperative URS and biopsy were neither a significant predictor of worse oncological outcomes nor of a specific treatment modality. CONCLUSIONS: The advantage in terms of OS and CSS in patients undergoing preoperative URS could derive from a better selection of candidates for curative treatment. The treatment strategy is likely more influenced by tumor features than by URS findings.

Symptomatic and functional recovery after transurethral resection of bladder tumor: Data from ecological momentary symptom assessment.

OBJECTIVES: To quantitatively describe the nature, severity, and duration of symptoms and functional impairment during recovery from transurethral resection of bladder tumors. MATERIALS AND METHODS: All patients scheduled for transurethral resection were approached for enrollment in a text-message based ecological momentary symptom assessment platform. Nine patients reported outcomes were measured 7 days before surgery and on postoperative days 1, 2, 3, 5, 7, 10, and 14 using a 5-point Likert scale. Self-reported degree of hematuria was collected using a visual scale. Clinical data was collected via retrospective chart review. RESULTS: A total of 159 patients were analyzed. Postoperative symptoms were overall mild, with the largest differences from baseline to postoperative day 1 seen in dysuria (median 0/5 vs. 3/5) and ability to work (median 5/5 vs. 4/5). Recovery was generally rapid, with 76% of patients reporting ≥4/5 agreement with the statement "I feel recovered from surgery" by postoperative day 2, although 15% of patients reported persistently lower levels of agreement on postoperative day 10 or 14. Patients undergoing larger resections (≥2cm) did take longer to return to baseline in multiple symptom domains, but the difference of medians vs. those undergoing smaller resections was less than 1 day across all domains. Multivariable analysis suggested that receiving perioperative intravesical chemotherapy was associated with longer time to recovery. 84% of patients reported clear yellow urine by postoperative day 3. CONCLUSION: In this population, hematuria and negative effects on quality of life resulting from transurethral resection of bladder tumors were generally mild and short-lived, although a small number of patients experienced longer recoveries.

High Interest in Injectable Opioid Agonist Treatment With Hydromorphone Among Urban Syringe Service Program Participants.

BACKGROUND: Injectable opioid agonist treatment with hydromorphone (iOAT-H) is effective for persons who inject drugs (PWID) with opioid use disorder (OUD) but remains unavailable in the United States. Our objective was to determine interest in iOAT-H among syringe services program (SSP) participants. METHODS: We recruited PWID with OUD from SSPs in New York City. Interest in iOAT-H was assessed on a 4-point scale. We compared participants who were and were not interested in iOAT-H regarding sociodemographic characteristics and self-reported variables (past 30 days): heroin use, public injection practices, and participation in illegal activity other than drug possession. Participants reported their preferred OUD treatment and reasons for these preferences. RESULTS: Of 108 participants, most were male (69%), Hispanic (68%), and median age was 42 years. The median number of prior OUD treatment episodes was 6 (interquartile range: 2-12). Most (65%) were interested in iOAT-H. Interested participants (vs not interested) reported, over the prior 30 days, greater heroin use days (mean, 26.4 vs 22.3), injecting in public more times (median, 15 vs 6), and a higher percentage having participated in illegal activity (40% vs 16%). Preferences for OUD treatment were: iOAT-H (43%), methadone (39%), and buprenorphine (9%). Participants who preferred iOAT-H to conventional OUD treatments reported preferring injection as a route of administration and that available OUD treatments helped them insufficiently. CONCLUSIONS: SSP participants with OUD reported high interest in iOAT-H. Participants had attempted conventional treatments but still used heroin almost daily. We identified PWID at risk for opioid-related harms who potentially could benefit from iOAT-H.

Real-time estimation of nephron activity with a linear measurement system (RENAL-MS) predicts postoperative estimated glomerular filtration rate.

OBJECTIVE: To determine whether a simple point-of-care measurement system estimating renal parenchymal volume using tools ubiquitously available could be used to replace nuclear medicine renal scintigraphy (NMRS) in current clinical practice to predict estimated glomerular filtration rate (eGFR) after nephrectomy by estimating preoperative split renal function. PATIENTS AND METHODS: We performed a retrospective review of patients who underwent abdominal cross-sectional imaging (computed tomography/magnetic resonance imaging) and mercaptoacetyltriglycine (MAG3) NMRS prior to total nephrectomy at a single institution. We developed the real-time estimation of nephron activity with a linear measurement system (RENAL-MS) method of estimating postoperative renal function via the following technique: renal parenchymal volume of the removed kidney relative to the remaining kidney was estimated as the product of renal length and the average of six renal parenchymal thickness measurements. The utility of this value was compared to the utility of the split renal function measured by MAG3 for prediction of eGFR and new onset Stage 3 chronic kidney disease (CKD) at ≥90 days after nephrectomy using uni- and multivariate linear and logistic regression. RESULTS: A total of 57 patients met the study criteria. The median (interquartile range [IQR]) age was 69 (61-80) years. The median (IQR) pre- and postoperative eGFR was 74 (IQR 58-90) and 46 (35-62) mL/min/1.73 m2 , respectively. [Correction added on 29 December 2023, after first online publication: The data numbers in the preceding sentence have been corrected.] Correlations between actual and predicted postoperative eGFR were similar whether the RENAL-MS or NMRS methods were used, with correlation using RENAL-MS being slightly numerically but not statistically superior (R = 0.82 and 0.76; P = 0.138). Receiver operating characteristic curve analysis using logistic regression estimates incorporating age, sex, and preoperative creatinine to predict postoperative Stage 3 CKD were similar between RENAL-MS and NMRS (area under the curve 0.93 vs. 0.97). [Correction added on 29 December 2023, after first online publication: The data numbers in the preceding sentence have been corrected.] CONCLUSION: A point-of-care tool to estimate renal parenchymal volume (RENAL-MS) performed equally as well as NMRS to predict postoperative eGFR and de novo Stage 3 CKD after nephrectomy in our population, suggesting NMRS may not be necessary in this setting.

Cost-Effectiveness Analysis for Therapy Sequence in Advanced Cancer: A Microsimulation Approach with Application to Metastatic Prostate Cancer.

PURPOSE: Patients with advanced cancer may undergo multiple lines of treatment, switching therapies as their disease progresses. We developed a general microsimulation framework to study therapy sequence and applied it to metastatic prostate cancer. METHODS: We constructed a discrete-time state transition model to study 2 lines of therapy. Using digitized published survival curves (progression-free survival, time to progression, and overall survival [OS]), we inferred event types (progression or death) and estimated transition probabilities using cumulative incidence functions with competing risks. We incorporated within-patient dependence over time; first-line therapy response informed subsequent event probabilities. Parameters governing within-patient dependence calibrated the model-based results to a target clinical trial. We applied these methods to 2 therapy sequences for metastatic prostate cancer, wherein both docetaxel (DCT) and abiraterone acetate (AA) are appropriate for either first- or second-line treatment. We assessed costs and quality-adjusted life-years (5-y QALYs) for 2 treatment strategies: DCT → AA versus AA → DCT. RESULTS: Models assuming within-patient independence overestimated OS time, which corrected with the calibration approach. With generic pricing, AA → DCT dominated DCT → AA, (higher 5-y QALYs and lower costs), consistent for all values of calibration parameters (including no correction). Model calibration increased the difference in 5-y QALYs between treatment strategies (0.07 uncorrected v. 0.15 with base-case correction). Applying the correction decreased the estimated difference in cost (-$5,360 uncorrected v. -$3,066 corrected). Results were strongly affected by the cost of AA. Under a lifetime horizon, AA → DCT was no longer dominant but still cost-effective (incremental cost-effectiveness ratio: $19,463). CONCLUSIONS: We demonstrate a microsimulation approach to study the cost-effectiveness of therapy sequences for advanced prostate cancer, taking care to account for within-patient dependence. HIGHLIGHTS: We developed a discrete-time state transition model for studying therapy sequence in advanced cancers.Results are sensitive to dependence within patients.A calibration approach can introduce dependence across lines of therapy and closely match simulation outcomes to target trial outcomes.

Diabetes, Obesity, and Pathological Upstaging in Renal Cell Carcinoma: Results From a Large Multi-institutional Consortium.

PURPOSE: We sought to determine whether clinical risk factors and morphometric features on preoperative imaging can be utilized to identify those patients with cT1 tumors who are at higher risk of upstaging (pT3a). MATERIALS AND METHODS: We performed a retrospective international case-control study of consecutive patients treated surgically with radical or partial nephrectomy for nonmetastatic renal cell carcinoma (cT1 N0) conducted between January 2010 and December 2018. Multivariable logistic regression models were used to study associations of preoperative risk factors on pT3a pathological upstaging among all patients, as well as subsets with those with preoperative tumors ≤4 cm, renal nephrometry scores, tumors ≤4 cm with nephrometry scores, and clear cell histology. We also examined association with pT3a subsets (renal vein, sinus fat, perinephric fat). RESULTS: Among the 4,092 partial nephrectomy and 2,056 radical nephrectomy patients, pathological upstaging occurred in 4.9% and 23.3%, respectively. Among each group independent factors associated with pT3a upstaging were increasing preoperative tumor size, increasing age, and the presence of diabetes. Specifically, among partial nephrectomy subjects diabetes (OR=1.65; 95% CI 1.17, 2.29), male sex (OR=1.62; 95% CI 1.14, 2.33), and increasing BMI (OR=1.03; 95% CI 1.00, 1.05 per 1 unit BMI) were statistically associated with upstaging. Subset analyses identified hilar tumors as more likely to be upstaged (partial nephrectomy OR=1.91; 95% CI 1.12, 3.16; radical nephrectomy OR=2.16; 95% CI 1.44, 3.25). CONCLUSIONS: Diabetes and higher BMI were associated with pathological upstaging, as were preoperative tumor size, increased age, and male sex. Similarly, hilar tumors were frequently upstaged.

Female sexual function evaluation and intraoperative vaginal reconstruction in bladder cancer.

RC significantly negatively impacts sexual function (SF) in both men and women. While significant research resources have been allocated to examine the deleterious effects of post prostatectomy erectile dysfunction, little attention has been directed towards female sexual function and organ preservation post cystectomy. These academic shortcomings often result in poor provider awareness and inadequate preoperative assessment. As such, it is crucial for all providers involved in female RC care to understand the necessary and available tools for preoperative evaluation, in addition to the anatomic and reconstructive techniques. This review aims to summarize the current preoperative evaluation and available tools of SF assessment and describe in detail the varying operative techniques in the preservation or restoration of SF in women after RC. The review explores the intricacies of preoperative evaluation tools, and intraoperative techniques for organ- and nerve-sparing during radical cystectomy in females. Particular emphasis on vaginal reconstruction after partial or complete resection is provided, including split-thickness skin (STF) graft vaginoplasy, pedicled flaps, myocutaneous flaps and use of bowel segments. In conclusion, this narrative review highlights the importance of understanding anatomic considerations and nerve-sparing strategies in promoting postoperative SF and quality of life. Furthermore, the review describes the advantages and limitations of each organ- and nerve-sparing technique and their impact on sexual function and overall well-being.

Treatment History and Interest in Injectable Opioid Agonist Treatment With Hydromorphone Among People Who Inject Drugs.

OBJECTIVES: Injectable opioid agonist treatment (iOAT) is a novel approach to treating opioid use disorder (OUD) that is typically reserved for treatment-experienced persons who inject drugs (PWID) with long-standing OUD. This study examined PWID's past OUD treatment histories and their attitudes toward iOAT with hydromorphone. METHODS: This cross-sectional study recruited syringe services program participants with OUD in New York City. Participants self-reported past OUD care episodes (detoxification; outpatient, inpatient, or medication treatment; or mutual aid groups) and current interest in iOAT with hydromorphone (assessed on a 4-point scale with 3 or 4 considered "interested"). Participants with 2 or more treatment episodes in the past 5 years were considered treatment-experienced. We examined whether the number of past care episodes was associated with interest in iOAT. RESULTS: Of 108 PWID, most participants were male (68.5%) and Hispanic (68.5%) with a mean age of 43 years (±10.8). Nearly all (98.1%) had severe OUD and had received past OUD care (96.3%), with the mean number of care episodes being 17.4 (SD, ±15.9). Most participants (59.8%) were treatment-experienced. Interest in iOAT with hydromorphone was high (64.8%), but there was no significant association between total past care episodes and expressing interest in iOAT (odds ratio, 1.02; 95% confidence interval, 0.99-1.05). CONCLUSION: Participants were highly treatment-experienced, and iOAT interest was high regardless of prior OUD treatment. New OUD treatment options, such as iOAT with hydromorphone, would be welcomed by PWID whose OUD has not remitted with conventional treatment as well as other PWID.

Clinical Performance of Technetium-99m-Sestamibi SPECT/CT Imaging in Differentiating Oncocytic Tumors From Renal Cell Carcinoma in Routine Clinical Practice.

PURPOSE: Technetium-99m-sestamibi single-photon emission CT/x-ray CT is an emerging clinical tool to differentiate oncocytic tumors from renal cell carcinomas. We report data from a large institutional cohort of patients who underwent technetium-99m-sestamibi scans during evaluation of renal masses. MATERIALS AND METHODS: Patients who underwent technetium-99m-sestamibi single-photon emission CT/x-ray CT between February 2020 and December 2021 were included in the analysis. Scans were defined as "hot" for oncocytic tumor when technetium-99m-sestamibi uptake was qualitatively equivalent or higher between the mass of interest and normal renal parenchyma, suggesting oncocytoma, hybrid oncocytic/chromophobe tumor, or chromophobe renal cell carcinoma. Demographic, pathological, and management strategy data were compared between "hot" and "cold" scans. For individuals who underwent diagnostic biopsy or extirpative procedures, the concordance between radiological findings and pathology was indexed. RESULTS: A total of 71 patients (with 88 masses) underwent technetium-99m-sestamibi imaging with 60 (84.5%) patients having at least 1 "cold" mass on imaging and 11 (15.5%) patients exhibiting only "hot" masses. Pathology was available for 7 "hot" masses, with 1 biopsy specimen (14.3%) being discordant (clear cell renal cell carcinoma). Five patients with "cold" masses underwent biopsy. Out of 5 biopsied masses, 4 (80%) were discordant oncocytomas. Of the extirpated specimens, 35/40 (87.5%) harbored renal cell carcinoma and 5/40 (12.5%) yielded discordant oncocytomas. In sum, 20% of pathologically sampled masses that were "cold" on technetium-99m-sestamibi imaging still harbored oncocytoma/hybrid oncocytic/chromophobe tumor/chromophobe renal cell carcinoma. CONCLUSIONS: Further work is needed to define utility of technetium-99m-sestamibi in real-world clinical practice. Our data suggest this imaging strategy is not yet ready to replace biopsy.

Sequential intravesical gemcitabine-docetaxel vs. bacillus Calmette-Guerin (BCG) in the treatment of non-muscle invasive bladder cancer: A preliminary cost-effectiveness analysis.

INTRODUCTION: Treatment naïve patients with high-risk non-muscle invasive bladder cancer (NMIBC) are treated with bacillus Calmette-Guérin (BCG) therapy as the standard of care. Recently, intravesical sequential gemcitabine-docetaxel in the BCG-naïve setting was shown to be well-tolerated and effective, raising the possibility of a new first line intravesical therapy. Cost effectiveness of this intervention remains unknown; therefore, we designed a cost effectiveness study evaluating BCG vs. sequential gemcitabine-docetaxel in patients with high risk NMIBC. METHODS: Using TreeAgePro 2019 software, we developed a Markov model to evaluate BCG vs. gemcitabine-docetaxel from the U.S. Medicare perspective with a 2-year time horizon. Model probabilities and utilities were derived from published literature. Direct costs were obtained from Medicare cost databases. Our primary outcomes were effectiveness (measured in quality adjusted life years [QALYs]), cost and the incremental cost-effectiveness ratio with a willingness to pay threshold of $100,000. RESULTS: Our results indicate that while both treatments resulted in similar QALYs of 1.76, the mean costs per patient at 2 years were $12,363 and $7,090 for BCG and gemcitabine-docetaxel, respectively. Therefore, the BCG strategy was dominated by the gemcitabine-docetaxel strategy as it was equally effective and less costly. One way sensitivity analyses were completed and gemcitabine-docetaxel remained a cost-effective strategy. CONCLUSIONS: The findings of this preliminary cost-effectiveness analysis are novel in that they highlight a well tolerated, efficacious drug that is less expensive than the traditional gold standard therapy. In modern medicine, we are more often challenged by agents with marginally increased efficacy but at significantly higher costs; gemcitabine-docetaxel represents a rare entity which is a success for both patients and healthcare systems alike.

Protocol of a multicentre randomised controlled trial assessing transperineal prostate biopsy to reduce infectiouscomplications.

INTRODUCTION: Approximately one million prostate biopsies are performed annually in the USA, and most are performed using a transrectal approach under local anaesthesia. The risk of postbiopsy infection is increasing due to increasing antibiotic resistance of rectal flora. Single-centre studies suggest that a clean, percutaneous transperineal approach to prostate biopsy may have a lower risk of infection. To date, there is no high-level evidence comparing transperineal versus transrectal prostate biopsy. We hypothesise that transperineal versus transrectal prostate biopsy under local anaesthesia has a significantly lower risk of infection, similar pain/discomfort levels and comparable detection of non-low-grade prostate cancer. METHODS AND ANALYSIS: We will perform a multicentre, prospective randomised clinical trial to compare transperineal versus transrectal prostate biopsy for elevated prostate-specific antigen in the first biopsy, prior negative biopsy and active surveillance biopsy setting. Prostate MRI will be performed prior to biopsy, and targeted biopsy will be conducted for suspicious MRI lesions in addition to systematic biopsy (12 cores). Approximately 1700 men will be recruited and randomised in a 1:1 ratio to transperineal versus transrectal biopsy. A streamlined design to collect data and to determine trial eligibility along with the two-stage consent process will be used to facilitate subject recruitment and retention. The primary outcome is postbiopsy infection, and secondary outcomes include other adverse events (bleeding, urinary retention), pain/discomfort/anxiety and critically, detection of non-low-grade (grade group ≥2) prostate cancer. ETHICS AND DISSEMINATION: The Institutional Review Board of the Biomedical Research Alliance of New York approved the research protocol (protocol number #18-02-365, approved 20 April 2020). The results of the trial will be presented at scientific conferences and published in peer-reviewed medical journals. TRIAL REGISTRATION NUMBER: NCT04815876.

Global Meta-analysis of Urine Microbiome: Colonization of Polycyclic Aromatic Hydrocarbon-degrading Bacteria Among Bladder Cancer Patients.

BACKGROUND: The application of next-generation sequencing techniques has enabled characterization of urinary tract microbiome. Although many studies have demonstrated associations between the human microbiome and bladder cancer (BC), these have not always reported consistent results, thereby necessitating cross-study comparisons. Thus, the fundamental questions remain how we can utilize this knowledge. OBJECTIVE: The aim of our study was to examine the disease-associated changes in urine microbiome communities globally utilizing a machine learning algorithm. DESIGN, SETTING, AND PARTICIPANTS: Raw FASTQ files were downloaded for the three published studies in urinary microbiome in BC patients, in addition to our own prospectively collected cohort. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Demultiplexing and classification were performed using the QIIME 2020.8 platform. De novo operational taxonomic units were clustered using the uCLUST algorithm and defined by 97% sequence similarity and classified at the phylum level against the Silva RNA sequence database. The metadata available from the three studies included were used to evaluate the differential abundance between BC patients and controls via a random-effect meta-analysis using the metagen R function. A machine learning analysis was performed using the SIAMCAT R package. RESULTS AND LIMITATIONS: Our study includes 129 BC urine and 60 healthy control samples across four different countries. We identified a total of 97/548 genera to be differentially abundant in the BC urine microbiome compared with that of healthy patients. Overall, while the differences in diversity metrics were clustered around the country of origin (Kruskal-Wallis, p < 0.001), collection methodology was a driver of microbiome composition. When assessing dataset from China, Hungary, and Croatia, data demonstrated no discrimination capacity to distinguish between BC patients and healthy adults (area under the curve [AUC] 0.577). However, inclusion of samples with catheterized urine improved the diagnostic accuracy of prediction for BC to AUC 0.995, with precision-recall AUC = 0.994. Through elimination of contaminants associated with the collection methodology among all cohorts, our study identified increased abundance of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria Sphingomonas, Acinetobacter, Micrococcus, Pseudomonas, and Ralstonia to be consistently present in BC patients. CONCLUSIONS: The microbiota of the BC population may be a reflection of PAH exposure from smoking, environmental pollutants, and ingestion. Presence of PAHs in the urine of BC patients may allow for a unique metabolic niche and provide necessary metabolic resources where other bacteria are not able to flourish. Furthermore, we found that while compositional differences are associated with geography more than with disease, many are driven by the collection methodology. PATIENT SUMMARY: The goal of our study was to compare the urine microbiome of bladder cancer patients with that of healthy controls and evaluate any potential bacteria that may be more likely to be found in patients with bladder cancer. Our study is unique as it evaluates this across multiple countries, to find a common pattern. After we removed some of the contamination, we were able to localize several key bacteria that are more likely to be found in the urine of bladder cancer patients. These bacteria all share their ability to break down tobacco carcinogens.

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

Treatment with neoadjuvant chemotherapy (NAC) in muscle invasive bladder cancer (MIBC) is associated with clinical benefit in urothelial carcinoma. While extensive research evaluating role of tumor mutational expression profiles and clinicopathologic factors into chemoresponse has been published, the role of gut microbiome (GM) in bladder cancer in chemoresponse has not been thoroughly evaluated. A working knowledge of the microbiome and its effect on all forms of cancer therapy in BC is critical. Here we examine gut microbiome of bladder cancer patients undergoing NAC. Overall, there was no significant difference in alpha and beta diversity by responder status. However, analysis of fecal microbiome samples showed that a higher abundance of Bacteroides within both institutional cohorts during NAC was associated with residual disease at the time of radical cystectomy regardless of chemotherapy regimen. Group community analysis revealed presence of favorable microbial subtypes in complete responders. Finally, fecal microbial composition outperformed clinical variables in prediction of complete response (AUC 0.88 vs AUC 0.50), however, no single microbial species could be regarded as a fully consistent biomarker. Microbiome-based community signature as compared to single microbial species is more likely to be associated as the link between bacterial composition and NAC response.