Characteristics and clinical significance of histological variants of bladder cancer

CT and MRI features of sarcomatoid urothelial carcinoma of the bladder and its differential diagnosis with conventional urothelial carcinoma

BACKGROUND

Sarcomatoid urothelial carcinoma (SUC) is a rare and highly malignant form of bladder cancer with a poor prognosis. Currently, there is limited information on the imaging features of bladder SUC and reliable indicators for distinguishing it from conventional urothelial carcinoma (CUC). The objective of our study was to identify the unique imaging characteristics of bladder SUC and determine factors that aid in its differential diagnosis.

MATERIALS AND METHODS

This retrospective study enrolled 22 participants with bladder SUC and 61 participants with CUC. The clinical, pathologic, and CT/MRI data from both groups were recorded, and a comparison was conducted using univariate analysis and multinomial logistic regression for distinguishing SUC from CUC.

RESULTS

The majority of SUCs were located in the trigone of the bladder and exhibited large tumor size, irregular shape, low ADC values, Vesical Imaging-Reporting and Data System (VI-RADS) score ≥ 4, the presence of necrosis, and an invasive nature. Univariate analysis revealed significant differences in terms of tumor location, shape, the maximum long-axis diameter (LAD), the short-axis diameter (SAD), ADC-value, VI-RADS scores, necrosis, extravesical extension (EVE), pelvic peritoneal spread (PPS), and hydronephrosis/ureteral effusion (p < .001 ~ p = .037) between SUCs and CUCs. Multinomial logistic regression found that only SAD (p = .014) and necrosis (p = .003) emerged as independent predictors for differentiating between SUC and CUC. The model based on these two factors achieved an area under curve (AUC) of 0.849 in ROC curve analysis.

CONCLUSION

Bladder SUC demonstrates several distinct imaging features, including a high incidence of trigone involvement, large tumor size, and obvious invasiveness accompanied by necrosis. A bladder tumor with a large SAD and evidence of necrosis is more likely to be SUC rather than CUC.

The Prognostic Significance of Histological Subtypes in Patients with Muscle-Invasive Bladder Cancer: An Overview of the Current Literature

Bladder cancer (BC) is the tenth most commonly diagnosed malignancy worldwide. In approximately 25% of cases, it presents as a muscle-invasive disease, requiring a radical treatment. Traditionally, the mainstay of treatment has been radical cystectomy (RC), but in the last decade, bladder-sparing treatments have been gaining growing interest. In particular, trimodal therapy (TMT) seems to yield survival results comparable to RC with less morbidity and better quality of life (QoL) outcomes. In this scenario, we aimed at shedding light on the role of the histological subtypes (HS) of BC and their prognostic significance in muscle-invasive BC (MIBC), treated either surgically or with TMT. We performed a narrative review to provide an overview of the current literature on this topic. When compared with patients diagnosed with conventional urothelial carcinoma (UC) of the same disease stage, survival did not appear to be significantly worse across the reports. But when sub-analyzed for separate subtype, some appeared to be independently associated with adverse survival outcomes such as the micropapillary, plasmacytoid, small-cell, and sarcomatoid subtypes, whereas others did not. Moreover, the optimal management remains to be defined, also depending on the therapeutic susceptibility of each histology. From this perspective, multi-disciplinary assessment alongside the routine inclusion of such entities in randomized clinical trials appears to be essential.

The optimal number of induction chemotherapy cycles in clinically lymph node-positive bladder cancer

OBJECTIVE

To investigate the optimal number of induction chemotherapy cycles needed to achieve a pathological response in patients with clinically lymph node-positive (cN+) bladder cancer (BCa) who received three or four cycles of induction chemotherapy followed by consolidative radical cystectomy (RC) with pelvic lymph node dissection.

PATIENTS AND METHODS

We included 388 patients who received three or four cycles of cisplatin/gemcitabine or (dose-dense) methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC), followed by consolidative RC for cTanyN1-3M0 BCa. We compared pathological complete (pCR = ypT0N0) and objective response (pOR = yp ≤T1N0) between treatment groups. Predictors of pCR and/or pOR were assessed using uni- and multivariable logistic regression analysis. The secondary endpoints were overall (OS) and cancer-specific survival (CSS). We evaluated the association between the number of induction chemotherapy cycles administered and survival outcomes on multivariable Cox regression.

RESULTS

Overall, 101 and 287 patients received three or four cycles of induction chemotherapy, respectively. Of these, 72 (19%) and 128 (33%) achieved pCR and pOR response, respectively. The pCR (20%, 18%) and pOR (40%, 31%) rates did not differ significantly between patients receiving three or four cycles (P > 0.05). The number of cycles was not associated with pCR or pOR on multivariable logistic regression analyses. The 2-year OS estimates were 63% (95% confidence interval [CI] 0.53-0.74) and 63% (95% CI 0.58-0.7) for patients receiving three or four cycles, respectively. Receiving three vs four cycles was not associated with OS and CSS on uni- or multivariable Cox regression analyses.

CONCLUSION

Pathological response and survival outcomes did not differ between administering three or four induction chemotherapy cycles in patients with cN+ BCa. A fewer cycles (minimum three) may be oncologically sufficient in patients with cN+ BCa, while decreasing the wait for definitive local therapy in those patients who end up without a response to chemotherapy. This warrants further validation.

Current Advances in the Management of Nonurothelial Subtypes of Bladder Cancer

Urothelial cancer (UC) is the most common histology seen in bladder tumors. The 2022 WHO classification of urinary tract tumors includes a list of less common subtypes (formerly known as variants) for invasive UC which are considered high-grade tumors. This review summarizes the most recent advances in the management of selected nonurothelial subtypes of bladder cancer: squamous cell carcinoma, small cell carcinoma, sarcomatoid urothelial carcinoma, micropapillary carcinoma, plasmacytoid carcinoma, adenocarcinoma, and urachal carcinoma. The role of neoadjuvant and adjuvant chemotherapy has not been well characterized for most of these histologies, and prospective data are extremely limited. Participation in clinical trials is recommended in advanced disease.

Bioinformatics in urology - molecular characterization of pathophysiology and response to treatment

The application of bioinformatics has revolutionized the practice of medicine in the past 20 years. From early studies that uncovered subtypes of cancer to broad efforts spearheaded by the Cancer Genome Atlas initiative, the use of bioinformatics strategies to analyse high-dimensional data has provided unprecedented insights into the molecular basis of disease. In addition to the identification of disease subtypes - which enables risk stratification - informatics analysis has facilitated the identification of novel risk factors and drivers of disease, biomarkers of progression and treatment response, as well as possibilities for drug repurposing or repositioning; moreover, bioinformatics has guided research towards precision and personalized medicine. Implementation of specific computational approaches such as artificial intelligence, machine learning and molecular subtyping has yet to become widespread in urology clinical practice for reasons of cost, disruption of clinical workflow and need for prospective validation of informatics approaches in independent patient cohorts. Solving these challenges might accelerate routine integration of bioinformatics into clinical settings.

Determining the clinicopathological significance of the VI-RADS ≧4 group: a retrospective study

BACKGROUND

The Vesical Imaging Reporting and Data System (VI-RADS) is widely used for predicting muscle-invasive bladder cancer (MIBC). This study aimed to determine the clinicopathological significance of the VI-RADS ≧4 (VI≧4) group.

METHODS

Patients who underwent transurethral resections of bladder tumors during the study period and preoperative magnetic resonance imaging were considered. The patients were pathologically diagnosed with urothelial carcinoma (UC). We first compared the results of patients with VI-RADS scores of 3 and 4 to determine the cut-off score for MIBC; thereafter, the patients were divided into the VI≧4 and VI-RADS ≦3 (VI≦3) groups using VI-RADS. The clinicopathological significance of the VI≧4 group was examined retrospectively by comparing the characteristics of each group.

RESULTS

In total, 121 cases were examined, of which 28 were pathologically diagnosed with MIBC. Of the 28 MIBC cases, three (10.7%) had a VI-RADS score of ≦3, and 25 (89.3%) had a VI-RADS score of ≧4. Of the 93 NMIBC cases, 86 (92.5%) had a VI-RADS score of ≦3, and seven (7.5%) had a VI-RADS score of ≧4. The diagnostic performance of the VI-RADS with a cut-off score of 4 was 89.3% for sensitivity, 92.5% for specificity, and an area under the curve (AUC) of 0.91. Contrastingly, for a cut-off score of 3, the sensitivity was 89.3%, specificity was 62.0%, and AUC was 0.72. A VI-RADS score of ≥ 4 could predict MIBC. In the VI≧4 group, 30 of 32 (93.8%) patients had high-grade tumors. The VI≧4 group had significantly more high-grade bladder cancers than the VI≦3 group (p < 0.001 OR = 31.77 95%CI:8.47-1119.07). In addition, the VI≧4 group had more tumor necrosis (VI≧4 vs VI≦3, p < 0.001 OR = 7.46 95%CI:2.61-21.34) and more UC variant cases (VI≧4 vs VI≦3, p = 0.034 OR = 3.28 95%CI:1.05-10.25) than the VI≦3 group.

CONCLUSIONS

This study suggests that VI-RADS has a high diagnostic performance in predicting MIBC and that VI-RADS could diagnose high-grade tumors, necrosis, and UC variants.

Predicting individual outcomes after radical cystectomy in urothelial variants with Cancer of the Bladder Risk Assessment (COBRA) score

OBJECTIVE

To validate the Cancer of the Bladder Risk Assessment (COBRA) score in patients with urothelial variants.

METHODS

Epidemiological, clinical, radiological, and anatomopathological data were collected from patients with urothelial carcinoma who underwent radical cystectomy at the Institute of Cancer of São Paulo between May 2008 and December 2022. Patients with the presence of at least 10% of any urothelial variants in the radical cystectomy specimens' anatomopathological exam were included in the study. The COBRA score and derivatives were applied and correlated with oncological outcomes.

RESULTS

A total of 680 patients [482 men (70.9%) and 198 women (29.1%)]; 66 years (IQR 59-73) underwent radical cystectomy for bladder tumor, and of these patients, a total of 167 patients presented any type of urothelial variant. The median follow-up time was 28.77 months (IQR 12-85). The three most prevalent UV were squamous differentiation (50.8%), glandular differentiation (31.3%), and micropapillary differentiation (11.3%). The subtypes with the worst prognosis were sarcomatoid with a median survival of 8 months (HR 1.161; 95% CI 0.555-2.432) and plasmacytoid with 14 months (HR 1.466; 95% CI 0.528-4.070). The COBRA score for patients with micropapillary variants demonstrated good predictive accuracy for OS (log-rank P = 0.009; 95% IC 6.78-29.21) and CSS (log-rank P = 0.002; 95% IC 13.06-26.93).

CONCLUSIONS

In our study, the COBRA score proved an effective risk stratification tool for urothelial histological variants, especially for the micropapillary urothelial variant. It may be helpful in the prognosis evaluation of UV patients after radical cystectomy.

Mutational signature and prognosis in adenocarcinoma of the bladder

Adenocarcinoma of the bladder is a rare urinary bladder carcinoma with limited therapy options due to lack of molecular characterization. Here, we aimed to reveal the mutational and transcriptomic landscapes of adenocarcinoma of the bladder and assess any relationship with prognosis. Between February 2015 and June 2021, a total of 23 patients with adenocarcinoma of the bladder were enrolled. These included 16 patients with primary bladder adenocarcinomas and seven patients with urachal adenocarcinoma. Whole exome sequencing (16 patients), whole genome sequencing (16 patients), bulk RNA sequencing (RNA-seq) (19 patients), and single-cell RNA-seq (5 patients) were conducted for the specimens. Correlation analysis, survival analysis, and t-tests were also performed. Prevalent T>A substitutions were observed among somatic mutations, and major trinucleotide contexts included 5'-CTC-3' and 5'-CTG-3'. This pattern was mainly contributed by COSMIC signature 22 related to chemical carcinogen exposure (probably aristolochic acid), which has not been reported in bladder adenocarcinoma. Moreover, genes with copy number changes were also enriched in the KEGG term 'chemical carcinogenesis'. Transcriptomic analysis suggested high immune cell infiltration and luminal-like features in the majority of samples. Interestingly, a small fraction of samples with an APOBEC-derived mutational signature exhibited a higher risk of disease progression compared with samples with only a chemical carcinogen-related signature, confirming the molecular and prognostic heterogeneity of bladder adenocarcinoma. This study presents mutational and transcriptomic landscapes of bladder adenocarcinoma, and indicates that a chemical carcinogen-related mutational signature may be related to a better prognosis compared with an APOBEC signature in adenocarcinoma of the bladder. © 2024 The Pathological Society of Great Britain and Ireland.

One Size Fits Some: Approaching Rare Malignancies of the Urinary Tract

OPINION STATEMENT

Urothelial carcinoma is the predominant cancer of the urinary tract but when divergent and subtype histology (non-urothelial) are identified at time of pathologic diagnosis, therapeutic and diagnostic challenges transpire. To this end, pathologic review to confirm any non-urothelial histology is key since these subtypes can often be overlooked. Few prospective trials are dedicated to understanding these non-urothelial histologic types; however, current, and past trials did allow patients with these non-urothelial histologic types to enroll, and inferences can be made about treatment efficacy and survival. Existing treatment regimens for non-urothelial bladder cancers are akin to standard urothelial cancer regimens using surgical approaches for localized disease and platinum-based chemotherapy for advanced disease. The reported clinical trials, that will be discussed, center on non-urothelial histologic types. These studies, albeit limited, provide critical insight into tumor biology and response to standard platinum-based chemotherapy, immune checkpoint inhibitors, and antibody drug conjugates. The inclusion of non-urothelial histologic types will be essential for clinical trials in development to provide further therapeutic advances and provide essential efficacy data.

Integration of Computational Docking into Anti-Cancer Drug Response Prediction Models

Cancer is a heterogeneous disease in that tumors of the same histology type can respond differently to a treatment. Anti-cancer drug response prediction is of paramount importance for both drug development and patient treatment design. Although various computational methods and data have been used to develop drug response prediction models, it remains a challenging problem due to the complexities of cancer mechanisms and cancer-drug interactions. To better characterize the interaction between cancer and drugs, we investigate the feasibility of integrating computationally derived features of molecular mechanisms of action into prediction models. Specifically, we add docking scores of drug molecules and target proteins in combination with cancer gene expressions and molecular drug descriptors for building response models. The results demonstrate a marginal improvement in drug response prediction performance when adding docking scores as additional features, through tests on large drug screening data. We discuss the limitations of the current approach and provide the research community with a baseline dataset of the large-scale computational docking for anti-cancer drugs.

Current trends in the promising immune checkpoint inhibition and radiotherapy combination for locally advanced and metastatic urothelial carcinoma

Locally advanced and metastatic urothelial carcinoma (UC) remains a challenging malignancy, though several novel therapeutic drugs have been developed in recent years. Over the past decade, immune checkpoint inhibitors (ICI) have shifted the paradigm of therapeutic strategies for UC; however, only a limited number of patients respond to ICI. Since radiotherapy (RT) is widely known to induce systemic immune activation, it may boost the efficacy of ICI. Conversely, RT also causes exhaustion of cytotoxic T cells, and the activation and recruitment of immunosuppressive cells; ICI may help overcome these immunosuppressive effects. Therefore, the combination of ICI and RT has attracted attention in recent years. The therapeutic benefits of this combination therapy and its optimal regimen have not yet been determined through prospective studies. Therefore, this review article aimed to provide an overview of the current preclinical and clinical studies that illustrate the underlying mechanisms and explore the optimization of the RT regimen along with the ICI and RT combination sequence. We also analyzed ongoing prospective studies on ICI and RT combination therapies for metastatic UC. We noted that the tumor response to ICI and RT combination seemingly differs among cancer types. Thus, our findings highlight the need for well-designed prospective trials to determine the optimal combination of ICI and RT for locally advanced and metastatic UC.

Patient-derived organoids identify tailored therapeutic options and determinants of plasticity in sarcomatoid urothelial bladder cancer

Sarcomatoid Urothelial Bladder Cancer (SARC) is a rare and aggressive histological subtype of bladder cancer for which therapeutic options are limited and experimental models are lacking. Here, we report the establishment of a long-term 3D organoid-like model derived from a SARC patient (SarBC-01). SarBC-01 emulates aggressive morphological, phenotypical, and transcriptional features of SARC and harbors somatic mutations in genes frequently altered in sarcomatoid tumors such as TP53 (p53) and RB1 (pRB). High-throughput drug screening, using a library comprising 1567 compounds in SarBC-01 and conventional urothelial carcinoma (UroCa) organoids, identified drug candidates active against SARC cells exclusively, or UroCa cells exclusively, or both. Among those, standard-of-care chemotherapeutic drugs inhibited both SARC and UroCa cells, while a subset of targeted drugs was specifically effective in SARC cells, including agents targeting the Glucocorticoid Receptor (GR) pathway. In two independent patient cohorts and in organoid models, GR and its encoding gene NR3C1 were found to be significantly more expressed in SARC as compared to UroCa, suggesting that high GR expression is a hallmark of SARC tumors. Further, glucocorticoid treatment impaired the mesenchymal morphology, abrogated the invasive ability of SARC cells, and led to transcriptomic changes associated with reversion of epithelial-to-mesenchymal transition, at single-cell level. Altogether, our study highlights the power of organoids for precision oncology and for providing key insights into factors driving rare tumor entities.

The prognostic significance of histologic variant on survival outcomes in patients with metastatic urothelial carcinoma receiving immune checkpoint inhibitor therapy

BACKGROUND

While the treatment guidelines have been established for pure urothelial carcinoma (pUC), patients with variant type urothelial carcinoma (vUC) face limited effective treatment options. The effectiveness of immune checkpoint inhibitors (ICI) in patients with vUC remains uncertain and necessitates additional research.

METHOD

We conducted a retrospective, multicenter study to explore the effectiveness of ICI in patients with pUC or vUC in Taiwan. We evaluated the overall response rate (ORR) through univariate logistic regression analysis and examined the overall survival (OS) and progression-free survival (PFS) using Kaplan-Meier analysis. Additionally, we employed univariate and multivariate Cox proportional hazards models to analyze the data.

RESULT

A total of 142 patients (116 pUC, 26 vUC) were included in our final analysis. The ORR was marginally higher in patients with pUC compared to those with vUC (34.5% vs. 23.1%, p = 0.26). Among all patients, 12.9% with pUC achieved a complete response (CR) after ICI treatment, while no vUC cases achieved CR (p = 0.05). There were no significant differences in PFS (median 3.6 months vs. 4.1 months, p = 0.34) or OS (median 16.3 months vs. 11.0 months, p = 0.24) when comparing patients with pUC or vUC. In the subgroup analysis, patients with pUC who underwent first-line ICI treatment exhibited significantly improved OS compared to those with vUC (24.6 months vs. 9.1 months, p = 0.004).

CONCLUSION

The use of ICI as monotherapy is a feasible and effective treatment approach for patients with metastatic vUC.

Adenocarcinoma of the Bladder: Assessment of Survival Advantage Associated With Radical Cystectomy and Comparison With Urothelial Bladder Cancer

PURPOSE

To evaluate the association between radical cystectomy (RC) and cancer-specific mortality (CSM) in patients diagnosed with adenocarcinoma of the bladder (ACB). Moreover, to directly compare the survival advantage of RC between ACB vs. urothelial bladder cancer (UBC).

MATERIALS AND METHODS

Non-metastatic muscle-invasive ACB and UBC patients were identified within Surveillance, Epidemiology, and End Results database (SEER 2000-2018). All analyses were stratified between RC vs. no-RC, in either organ-confined (OC: T2N0M0) or non-organ-confined (NOC: T3-4N0M0 or TanyN1-3M0) stages. Propensity score matching (PSM), cumulative incidence plots, competing risks regression (CRR) analyses, and 3 months' landmark analyses were performed.

RESULTS

Overall, 1,005 ACB and 47,741 UBC patients were identified, of whom 475 (47%) and 19,499 (41%) were treated with RC, respectively. After PSM, comparison between RC vs. no-RC applied to 127 vs. 127 OC-ACB, 7,611 vs. 7,611 OC-UBC, 143 vs. 143 NOC-ACB, and 4,664 vs. 4,664 NOC-UBC patients. 36-month CSM rates in RC vs. no-RC patients were 14 vs. 44% in OC-ACB, 18 vs. 39% in OC-UBC, 49 vs. 66% in NOC-ACB, and 44 vs. 56% in NOC-UBC patients. In CRR analyses, the effect of RC on CSM yielded a hazard ratio of 0.37 in OC-ACB, of 0.45 in OC-UBC, of 0.65 in NOC-ACB and of 0.68 in NOC-UBC patients (all P values<0.001). Landmark analyses virtually perfectly replicated the results.

CONCLUSIONS

In ACB, regardless of stage, RC is associated with lower CSM. The magnitude of this survival advantage was greater in ACB than in UBC, even after control for immortal time bias.

Perioperative systemic therapy in muscle invasive bladder cancer: Current standard method, biomarkers and emerging strategies

Bladder cancer ranks as the 10th most common cancer type globally, and muscle-invasive disease accounts for approximately 25% of newly diagnosed bladder cancers. Despite definitive treatment, 50% of patients with muscle-invasive bladder cancer (MIBC) develop metastasis within 2 years, leading to death. Perioperative systemic therapy is generally recommended to control local relapse or distant metastasis after surgical resection for patients with MIBC. Cisplatin-based neoadjuvant chemotherapy followed by radical cystectomy is the current standard treatment to improve oncologic control and survival outcomes. Adjuvant chemotherapy is recommended for patients with pathological T3-4 or positive lymph nodes after radical cystectomy if no neoadjuvant chemotherapy was given. Nonetheless, perioperative systemic therapy is not applied widely because of its toxicity, and less than 25% of patients receive cisplatin-based neoadjuvant chemotherapy. Therefore, the development of predictive biomarkers for neoadjuvant chemotherapy efficacy and alternative effective regimens for cisplatin-ineligible patients are important. Furthermore, recently, novel anticancer agents such as immune checkpoint inhibitors and antibody-drug conjugates have proven survival benefits in the metastatic setting, thereby expanding their therapeutic applications to the perioperative setting for non-metastatic MIBC. Herein, we discuss the current status and future perspectives of perioperative systemic strategies for MIBC.

Impact of Epithelial Histological Types, Subtypes, and Growth Patterns on Oncological Outcomes for Patients with Nonmetastatic Prostate Cancer Treated with Curative Intent: A Systematic Review

CONTEXT

The optimal management for men with prostate cancer (PCa) with unconventional histology (UH) is unknown. The outcome for these cancers might be worse than for conventional PCa and so different approaches may be needed.

OBJECTIVE

To compare oncological outcomes for conventional and UH PCa in men with localized disease treated with curative intent.

EVIDENCE ACQUISITION

A systematic review adhering to the Referred Reporting Items for Systematic Reviews and Meta-Analyses was prospectively registered on PROSPERO (CRD42022296013) was performed in July 2021.

EVIDENCE SYNTHESIS

We screened 3651 manuscripts and identified 46 eligible studies (reporting on 1 871 814 men with conventional PCa and 6929 men with 10 different PCa UHs). Extraprostatic extension and lymph node metastases, but not positive margin rates, were more common with UH PCa than with conventional tumors. PCa cases with cribriform pattern, intraductal carcinoma, or ductal adenocarcinoma had higher rates of biochemical recurrence and metastases after radical prostatectomy than for conventional PCa cases. Lower cancer-specific survival rates were observed for mixed cribriform/intraductal and cribriform PCa. By contrast, pathological findings and oncological outcomes for mucinous and prostatic intraepithelial neoplasia (PIN)-like PCa were similar to those for conventional PCa. Limitations of this review include low-quality studies, a risk of reporting bias, and a scarcity of studies that included radiotherapy.

CONCLUSIONS

Intraductal, cribriform, and ductal UHs may have worse oncological outcomes than for conventional and mucinous or PIN-like PCa. Alternative treatment approaches need to be evaluated in men with these cancers.

PATIENT SUMMARY

We reviewed the literature to explore whether prostate cancers with unconventional growth patterns behave differently to conventional prostate cancers. We found that some unconventional growth patterns have worse outcomes, so we need to investigate if they need different treatments. Urologists should be aware of these growth patterns and their clinical impact.

The impact of histological variants in patients with upper tract urothelial carcinoma treated with radical nephroureterectomy

OBJECTIVE

To investigate the impact of histological variants (HV) in patients with upper tract urothelial carcinoma (UTUC) and analyze the potential association between HV and postoperative bladder recurrence.

MATERIALS AND METHODS

The medical records of UTUC patients treated with RNU at our center from January 2012 to December 2019 were retrospectively analyzed. Patients were grouped according to the types of HV. Clinicopathological features and prognostic factors were compared among groups.

RESULTS

A total of 629 patients were included in the study: 458 (73%) patients had pure urothelial carcinoma (PUC) and 171 (27%) patients had UTUC with HV. Squamous differentiation was the most common type (124 cases, 19%), followed by glandular differentiation (29 cases, 5.0%). Patients with HV had a higher proportion of T3 and T4 pathologic stages (P < 0.001) as well as high-grade disease (P = 0.002). In the univariate analysis, squamous differentiation and glandular differentiation were significantly associated with worse cancer-specific survival (CSS) (HR 2.22, 95% CI 1.62-3.04, P < 0.001; HR 1.90, 95% CI 1.13-3.20, P = 0.016). However, the multivariate analysis showed that this association became non-significant. We found that HV were associated with recurrent muscle-invasive bladder cancer (MIBC) after RNU and all patients had T2 and T3 initial tumor stages (P = 0.008, P < 0.001).

CONCLUSION

We found that UTUC patients with HV were associated with biologically aggressive disease and recurrent MIBC after RNU. The detection of bladder recurrence following surgery needs to be given more attention in advanced UTUC patients with HV.

Blood-Based Biomarkers as Prognostic Factors of Recurrent Disease after Radical Cystectomy: A Systematic Review and Meta-Analysis

Survival outcomes after radical cystectomy (RC) for bladder cancer (BCa) have not improved in recent decades; nevertheless, RC remains the standard treatment for patients with localized muscle-invasive BCa. Identification of the patients most likely to benefit from RC only versus a combination with systemic therapy versus systemic therapy first/only and bladder-sparing is needed. This systematic review and meta-analysis pools the data from published studies on blood-based biomarkers to help prognosticate disease recurrence after RC. A literature search on PubMed and Scopus was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Articles published before November 2022 were screened for eligibility. A meta-analysis was performed on studies investigating the association of the neutrophil-to-lymphocyte ratio (NLR), the only biomarker with sufficient data, with recurrence-free survival. The systematic review identified 33 studies, and 7 articles were included in the meta-analysis. Our results demonstrated a statistically significant correlation between elevated NLR and an increased risk of disease recurrence (HR 1.26; 95% CI 1.09, 1.45; p = 0.002) after RC. The systematic review identified various other inflammatory biomarkers, such as interleukin-6 or the albumin-to-globulin ratio, which have been reported to have a prognostic impact on recurrence after RC. Besides that, the nutritional status, factors of angiogenesis and circulating tumor cells, and DNA seem to be promising tools for the prognostication of recurrence after RC. Due to the high heterogeneity between the studies and the different cut-off values of biomarkers, prospective and validation trials with larger sample sizes and standardized cut-off values should be conducted to strengthen the approach in using biomarkers as a tool for risk stratification in clinical decision-making for patients with localized muscle-invasive BCa.

Conditional survival after radical cystectomy for non-metastatic muscle-invasive squamous cell carcinoma of the urinary bladder: A population-based analysis

PURPOSE

To assess the effect of event-free survival duration on cancer-specific mortality (CSM) after radical cystectomy (RC) in nonmetastatic muscle-invasive squamous cell carcinoma of the urinary bladder.

METHODS

RC patients treated for non-metastatic muscle-invasive squamous cell carcinoma of the urinary bladder were identified within the Surveillance, Epidemiology, and End Results database (2000-2018). Independent predictor status for CSM of T and N stage groupings (i.e., T2N0, T3N0, T4N0, and TanyN1-3) was tested in multivariable Cox-regression models. Conditional 5-year CSM-free estimates were assessed at baseline and at 4 specific event-free survival times (i.e. 6, 12, 18 and 24 months), within each of the 4 examined stage groups.

RESULTS

Of 981 RC patients, 206 (21%), 416 (42%), 152 (16%), and 207 (21%) were T2N0, T3N0, T4N0, and TanyN1-3, respectively. In multivariable Cox-regression models T3N0 (HR 1.94), T4N0 (HR 5.22), and TanyN1-3 (HR 6.62) were independent predictors of CSM, relative to T2N0. In conditional survival analyses based on 24 months event-free status, survival estimates were: 89% for T2N0 vs. 76% at baseline (Δ = 13%), 84% for T3N0 vs. 58% at baseline (Δ = 26%), 69% for T4N0 vs. 25% at baseline (Δ = 44%), 69% for TanyN1-3 vs. 22% at baseline (Δ = 47%).

CONCLUSIONS

Event-free status at 24 months of follow-up is associated with substantially higher CSM-free survival than when CSM-free survival is predicted at baseline. The magnitude of this effect is most pronounced in TanyN1-3 and T4N0 patients, intermediate in T3N0 and more modest, nonetheless important, in T2N0.

Anti-tumor effect of AZD8055 against bladder cancer and bladder cancer-associated macrophages

The increased activity of the mTOR pathway in bladder cancer has been extensively studied, but no satisfactory mTOR inhibitor has been found in bladder cancer. The role of AZD8055, a second-generation mTOR inhibitor, has not been reported in bladder cancer. Herein, we investigated the effects of AZD8055 on bladder cells and their interaction with macrophages in vivo and in vitro. In four bladder cancer cell lines, the phosphorylation of mTOR, AKT and S6K1 was suppressed by AZD8055. AZD8055 inhibited proliferation and induced G1 cell-cycle arrest and apoptosis of bladder cancer cells in a concentration-dependent manner. AZD8055 also inhibits the migration and invasion of bladder cancer cells by blocking EMT and MMP9. In addition, AZD8055 inhibited chemotaxis and M2 phenotype of macrophage after co-culture with bladder cancer cells. These anti-tumor effects of AZD8055 were verified in vivo. Our findings collectively demonstrated that low-dose AZD8055 induces cytotoxicity and apoptosis, and inhibits the Akt/mTOR activation, invasion and migration of bladder cancer. These findings also demonstrate that AZD8055 partially blocked the interactions of bladder cancer cells and macrophages. In conclusion, AZD8055 is a promising mTOR inhibitor for bladder cancer.

En-bloc resection of non-muscle invasive bladder cancer: does it really make a difference?

PURPOSE OF REVIEW

Transurethral resection of bladder tumour (TURBT) followed by pathology investigation of the obtained specimens is the initial step in the management of urinary bladder cancer (UBC). By following the basic principles of oncological surgery, en-bloc resection of bladder tumour (ERBT) aims to overcome the limitations associated with conventional transurethral resection, and to improve the quality of pathological specimens for a better decision making. The current bulk of evidence provides controversial results regarding the superiority of one technique over the other. The aim of this article is to summarize the recent data and provide evidence on this unanswered question.

RECENT FINDINGS

Despite heterogeneous and controversial data, ERBT seems to have a better safety profile and deliver higher quality pathologic specimens. However, the recent evidence failed to support the hypothesized oncological potential benefits of ERBT in the initial surgical treatment of patients with UBC.

SUMMARY

ERBT has gained increasing interest globally in the past decade. It continues to represent a promising strategy with a variety of features intended to solve the inherent limitations of TURBT. However, the current quality of evidence does not allow solid conclusions to be drawn about its presumed superiority compared with the conventional technique.

Bladder Preservation for Muscle-Invasive Bladder Cancer With Variant Histology

A growing body of evidence has shown bladder-preservation with chemo-radiotherapy achieves comparable survival to Radical Cystectomy (5-year OS 50%-70%) and superior quality of life outcomes for patients with muscle-invasive urothelial carcinoma of the bladder (UC). However, up to 55% of patients harbor variant histology and in this review we aim to clarify the role of bladder-preservation for this group. We first draw the distinction between urothelial carcinoma with divergent differentiation (UCDD) and non-urothelial carcinoma (NUC). UCDD is common, increasing in prevalence, and whilst each subtype may have its own characteristics current evidence suggests comparable outcomes with radical cystectomy and bladder-preservation. Non-urothelial carcinoma is a collection of distinct pathologies each deserving of its own management strategy. However, these tumors are rare, and evidence is generated from retrospective studies with significant inherent bias. Small cell carcinoma of the bladder has good evidence for bladder-preservation; however, other pathologies such as Squamous Cell Carcinoma and Adenocarcinoma are not well supported. We recommend careful multidisciplinary appraisal of the evidence for each subtype and honest patient discussion about the limited evidence before reaching management decisions. As we look to the future molecular-profiling may help better characterize these tumors and aid in treatment selection.

Radical cystectomy in non-metastatic sarcomatoid bladder cancer: A direct comparison vs urothelial bladder cancer

INTRODUCTION

The effect of radical cystectomy (RC) on cancer-specific mortality (CSM) is unclear in non-metastatic sarcomatoid bladder cancer (SBC) patients. We aimed to test the benefit of RC in SBC, and to perform a direct comparison vs urothelial bladder cancer (UCB).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (SEER 2001-2018) all non-metastatic SBC and UBC patients were identified. Endpoint of interest was CSM. Propensity score matching (PSM), cumulative incidence plots, competing risks regression (CRR) analyses, three-months landmark analyses, and sensitivity analyses were performed. All results were stratified according to organ-confined (OC: T₂N₀M₀) vs non-organ-confined (NOC: T_3-4N₀M₀ or T_anyN_1-3M₀) stages.

RESULTS

Of 554 SBC patients, 49 vs 51% harbored OC vs NOC stages. Of 47,741 UBC patients, 62 vs 38% harbored OC vs NOC stages. RC rates were 33 vs 67% in OC vs NOC-SBC patients, and 40 vs 60% in OC vs NOC-UBC patients. After 1:1 PSM, comparison between RC vs no-RC was performed in OC-SBC (67 patients per group), OC-UBC (7611 patients per group), NOC-SBC (63 patients per group), and NOC-UBC patients (4644 patients per group). CRR hazard ratios associated with RC vs no-RC were 0.37 (p < 0.001) in OC-SBC vs 0.45 (p < 0.001) in OC-UBC, and 0.56 (p = 0.01) in NOC-SBC vs 0.68 (p < 0.001) in NOC-UBC. These results were replicated in sensitivity and landmark analyses.

CONCLUSIONS

The protective effect of RC vs no-RC is stronger in SBC than UBC patients, regardless of OC vs NOC stages.

Follow-up of the Urethra and Management of Urethral Recurrence After Radical Cystectomy: A Systematic Review and Proposal of Management Algorithm by the European Association of Urology-Young Academic Urologists: Urothelial Carcinoma Working Group

CONTEXT

Surveillance of the urethra and management of urethral recurrence (UR) after radical cystectomy (RC) is an area with poor evidence.

OBJECTIVE

We aimed to summarize the available evidence and provide clinicians with practical recommendations on how to prevent and manage UR after RC for bladder cancer.

EVIDENCE ACQUISITION

The MEDLINE and EMBASE databases were searched during September 2021 for studies evaluating UR after RC. The primary endpoint was oncologic outcomes for patients who experienced UR depending on different surveillance and management approaches.

EVIDENCE SYNTHESIS

Forty-three studies were included in the quantitative synthesis. According to the currently available literature, a tight-knitted surveillance protocol should be implemented for males treated with RC and nonorthotopic neobladder diversion as well as patients with prostatic involvement, tumor multifocality, bladder neck involvement, and concomitant carcinoma in situ. A survival benefit of a prophylactic urethrectomy has been reported only in patients at very high risk for UR based on clinical factors. Surveillance protocols were highly heterogeneous and poorly documented among included studies. Patients whose UR was diagnosed based on clinical symptoms had a poor prognosis. Only limited data were available on the comparative effectiveness of watchful waiting after RC versus clinical symptom screening as part of a follow-up strategy. However, the use of regular cytology and/or urethroscopy seems useful in select patients at high risk for UR. Despite limited data on the optimal management of UR, urethra-sparing approaches (transurethral resection of UR) seem to be an option for Ta (only) recurrences; a salvage urethrectomy with or without chemotherapy should be the standard for all others.

CONCLUSIONS

Based on the currently available literature, we have proposed an algorithm to guide the decision-making process to help identify and treat UR after RC. Given the lack of evidence on how to deal with UR and surveil patients at risk for UR, this study may invigorate research in this area of unmet need.

PATIENT SUMMARY

Early diagnosis and tailored management of urethral recurrence could help improve oncologic outcomes in these patients.

Bladder Urothelial Carcinoma: Machine Learning-based Computed Tomography Radiomics for Prediction of Histological Variant

RATIONALE AND OBJECTIVES

Histological variant (HV) of bladder urothelial carcinoma (UC) is a significant factor for therapy management. We aim to assess the predictive performance of machine learning (ML)-based Computed Tomography radiomics of UC for HV.

MATERIALS AND METHODS

Volume of interest of 37 bladder UC tumors, of which 21 were pure and 16 were HV, were manually segmented. The extracted first- and second-order texture features (n = 117) using 3-D Slicer radiomics were compared to the radical cystectomy histopathological results. ML algorithms were performed to determine the significant models using Python 2.3, Pycaret library. The sample size was increased to 74 by synthetic data generation, and three outliers from the training set were removed (training dataset; n = 52, test dataset; n = 19). The predictive performances of 15 ML algorithms were compared. Then, the best two models were evaluated on the test set and ensembled by Voting Classifier.

RESULTS

The ML algorithms demonstrated area under curve (AUC) and accuracy ranging 0.79-0.97 and 50%-90%, respectively on the train set. The best models were Gradient Boosting Classifier (AUC: 0.95, accuracy: 90%) and CatBoost Classifier (AUC: 0.97, accuracy: 85%). On the test set; the Voting Classifier of these two models demonstrated AUC, accuracy, recall, precision, and F1 scores as follows; 0.93, 79%, 86%, 67%, and 75%, respectively.

CONCLUSION

ML-based Computed Tomography radiomics of UC can predict HV, a prognostic factor that is indeterminable by qualitative radiological evaluation and can be missed in the preoperative histopathological specimens.

Expression of Nectin-4 in Variant Histologies of Bladder Cancer and Its Prognostic Value-Need for Biomarker Testing in High-Risk Patients?

Variant histologies of bladder cancer (BC) often present with advanced tumor stage and the status of perioperative therapy is unclear. Thereby, squamous cell carcinoma (SCC), adenocarcinoma (ADENO), and sarcomatoid urothelial carcinoma (SARCO) are the most frequent variants. Nectin-4 has emerged as a highly interesting target in BC and might guide therapeutic application of antibody−drug conjugates (ADC). We therefore aimed to investigate expression patterns and prognostic value of Nectin-4 in variant histologies of BC. A single-center retrospective analysis was conducted of patients who underwent radical cystectomy (RC) for BC and revealed variant histologies of BC in the final specimens. Immunohistochemical staining for Nectin-4 was performed on tissue microarrays with 59 SCC, 22 ADENO, and 24 SARCO, and Nectin-4 expression was scored using the histochemical scoring system (H-score). Overall survival (OS) and progression-free survival (PFS) was calculated by Kaplan−Meier method. Median expression of Nectin-4 was 150 (range 0−250) in SCC, 140.5 (range 30−275) in ADENO, and 10 (0−185) in SARCO, with significantly lower levels for SARCO compared to SCC or ADENO (p < 0.001). For SCC, ADENO or SARCO no differences regarding OS or PFS were observed based on Nectin-4 expression levels (p > 0.05). Multivariate analysis revealed nodal stage as an independent prognostic factor for OS and PFS and metastases for PFS but not Nectin-4 expression. In conclusion, Nectin-4 was not prognostic in histological subtypes of BC in our study cohort. However, the high expression of Nectin-4 in SCC and ADENO might guide future treatment with novel Nectin-4-directed ADCs and provide this high-risk patient collective with a new promising therapeutic option. Testing Nectin-4 expression as a biomarker should be considered in trials with SARCO, where low Nectin-4 expression has been observed.

Survival Outcomes After Immediate Radical Cystectomy Versus Conservative Management with Bacillus Calmette-Guérin Among T1 High-grade Micropapillary Bladder Cancer Patients: Results from a Multicentre Collaboration

BACKGROUND

Literature lacks clear evidence regarding the optimal treatment for non-muscle-invasive micropapillary bladder cancer (MPBC) due to its rarity and the presence of only small sample size and single-centre studies.

OBJECTIVE

To assess cancer-specific mortality (CSM) and overall mortality (OM) between immediate radical cystectomy (RC) and conservative management among T1 high-grade (HG) MPBC.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively analysed a multicentre dataset including 119 T1 HG MPBC patients treated between 2005 and 2019 at 15 tertiary referral centres. The median follow-up time was 35 mo (interquartile range: 19-64).

INTERVENTION

Patients underwent immediate RC versus conservative management with bacillus Calmette-Guérin.

OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS

Cumulative incidence functions and Kaplan-Meier methods were applied to estimate survival outcomes. Multivariable Cox analyses were performed to assess independent predictors of disease recurrence and disease progression after conservative management; covariates consisted of pure MPBC, concomitant lymphovascular invasion (LVI), and carcinoma in situ at initial diagnosis.

RESULTS AND LIMITATIONS

Immediate RC and conservative management were performed in 27% and 73% of patients, respectively. CSM and OM did not differ significantly among patient treated with immediate RC versus conservative management (Pepe-Mori test p = 0.5 and log-rank test p = 0.9, respectively). Overall, 66.7% and 34.5% of patients experienced disease recurrence and disease progression after conservative management, respectively. At multivariable Cox analyses, concomitant LVI was an independent predictor of disease recurrence (p = 0.01) and progression (p = 0.03), while pure MPBC was independently associated with disease progression (p = 0.03). The absence of a centralised re-review and the retrospective design represent the main limitations of our study.

CONCLUSIONS

Conservative management could achieve satisfactory results among T1 HG MPBC patients with neither pure MPBC nor LVI at initial diagnosis.

PATIENT SUMMARY

Bacillus Calmette-Guérin seems to be an effective therapy for T1 micropapillary bladder cancer patients with neither pure micropapillary disease nor lymphovascular invasion at initial diagnosis.

Complete transurethral resection of bladder tumor before radical cystectomy is not a risk factor for organ-confined bladder cancer: A case-control study

Objectives

Materials and methods

Results

Conclusions

Micropapillary bladder cancer: an evolving biology

PURPOSE OF REVIEW

To summarize a comprehensive overview of more recent evidence on micropapillary bladder cancer (MPBC), focusing on actual incidence, clinical features, therapeutic strategies, and prognosis.

RECENT FINDINGS

MPBC generally exhibits an aggressive behaviour compared with pure urothelial carcinoma (pUC) with advances in tumour stage and nodal and distant spread at diagnosis. Due to its rarity and presence of only small sample size and retrospective studies, no consensus currently exists regarding the most effective therapeutic strategy to be performed among nonmuscle-invasive (conservative treatment versus immediate radical cystectomy) and muscle-invasive MPBC (neoadjuvant therapy versus upfront radical cystectomy versus adjuvant chemotherapy).

SUMMARY

The incidence of MPBC is recently increased according to latter literature, ranging from 2.9 to 7.6% of all bladder cancer. Despite its aggressive behaviour at time of presentation, more recent evidence fails to demonstrate a significant association between MPBC and worse outcomes compared with pUC when adjusted for clinical and pathological features. According to latter evidence, MPBC pathological response to NAC appears to be unsatisfactory compared with pUC patients while neoadjuvant immunotherapy with Pembrolizumab may represent an effective treatment among MPBC patients, based on PD-L1 and TMB expression.

Neoadjuvant and Adjuvant Chemotherapy for Variant Histology Bladder Cancers: A Systematic Review and Meta-Analysis

Context

To improve the prognosis of variant histology (VH) bladder cancers, clinicians have used neoadjuvant chemotherapy (NAC) or adjuvant chemotherapy (AC) on the basis of radical cystectomy (RC). Despite some new data, the evidence remains mixed on their efficacy.

Objective

To update the current evidence on the role of NAC and AC for VH bladder cancers.

Evidence Acquisition

We searched for all studies investigating NAC or AC for bladder cancer patients with variant histology in PubMed, Embase, and the Cochrane Central Register of Controlled Trials up to December 2021. The primary end points were recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS).

Evidence Synthesis

We identified 18 reports comprising a total of 10,192 patients in the NAC studies. In patients with VH, the use of NAC did improve CSS (hazard ratio [HR] 0.74, 95% confidence interval [CI] 0.55–0.99, p = 0.044), and OS (HR 0.74, 95% CI 0.66–0.84, p = 0.000), but not RFS (HR 1.15, 95% CI 0.56–2.33, p = 0.706). Subgroup analyses demonstrated that receiving NAC was associated with better OS in sarcomatoid VH (HR 0.67, 95% CI 0.54–0.83, p = 0.000) and neuroendocrine VH (HR 0.54, 95% CI 0.43–0.68, p = 0.000). For AC, we identified eight reports comprising a total of 3254 patients. There was a benefit in CSS (HR 0.61, 95% CI 0.43–0.87, p = 0.006) and OS (HR 0.76, 95% CI 0.60–0.98, p = 0.032). Subgroup analyses demonstrated that only neuroendocrine VH had better CSS (HR 0.29, 95% CI 0.13–0.67, p = 0.174) when receiving AC.

Conclusions

NAC or AC for VH bladder cancers confers an OS and CSS benefit compared with RC alone. For NAC, the benefit was independently observed in the sarcomatoid and neuroendocrine subgroups. As for AC, only neuroendocrine subgroups improved CSS.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021289487.

The Impact of Primary Versus Secondary Muscle-invasive Bladder Cancer at Diagnosis on the Response to Neoadjuvant Chemotherapy

Background

Objective

Design, setting, and participants

Outcome measurements and statistical analysis

Results and limitations

Conclusions

Patient summary

Role of microRNAs in regulation of WNT signaling pathway in urothelial and prostate cancers

Background

Urothelial cancer (UC) and prostate cancer (PCa) are the most common cancers among men with a high ratio of mortality in advanced-stages. The higher risk of these malignancies among men can be associated with higher carcinogens exposure. Molecular pathology of UC and PCa is related to the specific mutations and aberrations in some signaling pathways. WNT signaling is a highly regulated pathway that has a pivotal role during urothelial and prostate development and homeostasis. This pathway also plays a vital role in adult stem cell niches to maintain a balance between stemness and differentiation. Deregulation of the WNT pathway is frequently correlated with tumor progression and metastasis in urothelial and prostate tumors. Therefore, regulatory factors of WNT pathways are being investigated as diagnostic or prognostic markers and novel therapeutic targets during urothelial and prostate tumorigenesis. MicroRNAs (miRNAs) have a pivotal role in WNT signaling regulation in which there are interactions between miRNAs and WNT signaling pathway during tumor progression. Since, the miRNAs are sensitive, specific, and noninvasive, they can be introduced as efficient biomarkers of tumor progression.

Main body

In present review, we have summarized all of the miRNAs that have been involved in regulation of WNT signaling pathway in urothelial and prostate cancers.

Conclusions

It was observed that miRNAs were mainly involved in regulation of WNT signaling in bladder cancer cells through targeting the WNT ligands and cytoplasmic WNT components such as WNT5A, WNT7A, CTNNB1, GSK3β, and AXIN. Whereas, miRNAs were mainly involved in regulation of WNT signaling in prostate tumor cells via targeting the cytoplasmic WNT components and WNT related transcription factors such as CTNNB1, GSK3β, AXIN, TCF7, and LEF1. MiRNAs mainly functioned as tumor suppressors in bladder and prostate cancers through the WNT signaling inhibition. This review paves the way of introducing a noninvasive diagnostic panel of WNT related miRNAs in urothelial and prostate tumors.

Molecular profile of pure squamous cell carcinoma of the bladder identifies major roles for OSMR and YAP signalling

Pure squamous cell carcinoma (SCC) is the most common pure variant form of bladder cancer, found in 2–5% of cases. It often presents late and is unresponsive to cisplatin‐based chemotherapy. The molecular features of these tumours have not been elucidated in detail. We carried out whole‐exome sequencing (WES), copy number, and transcriptome analysis of bladder SCC. Muscle‐invasive bladder cancer (MIBC) samples with no evidence of squamous differentiation (non‐SD) were used for comparison. To assess commonality of features with urothelial carcinoma with SD, we examined data from SD samples in The Cancer Genome Atlas (TCGA) study of MIBC. TP53 was the most commonly mutated gene in SCC (64%) followed by FAT1 (45%). Copy number analysis revealed complex changes in SCC, many differing from those in samples with SD. Gain of 5p and 7p was the most common feature, and focal regions on 5p included OSMR and RICTOR. In addition to 9p deletions, we found some samples with focal gain of 9p24 containing CD274 (PD‐L1). Loss of 4q35 containing FAT1 was found in many samples such that all but one sample analysed by WES had FAT1 mutation or deletion. Expression features included upregulation of oncostatin M receptor (OSMR), metalloproteinases, metallothioneins, keratinisation genes, extracellular matrix components, inflammatory response genes, stem cell markers, and immune response modulators. Exploration of differentially expressed transcription factors identified BNC1 and TFAP2A, a gene repressed by PPARG, as the most upregulated factors. Known urothelial differentiation factors were downregulated along with 72 Kruppel‐associated (KRAB) domain‐containing zinc finger family protein (KZFP) genes. Novel therapies are urgently needed for these tumours. In addition to upregulated expression of EGFR, which has been suggested as a therapeutic target in basal/squamous bladder cancer, we identified expression signatures that indicate upregulated OSMR and YAP/TAZ signalling. Preclinical evaluation of the effects of inhibition of these pathways alone or in combination is merited.

Accuracy and prognostic value of radiological lymph node features in variant histologies of bladder cancer

Purpose

To provide first evidence of lymph node (LN) staging using CT scan and its prognostic value in variant histologies of bladder cancer. This knowledge may optimize patient management with variant histologies based on CT morphological findings.

Methods

Preoperative CT scans of patients with variant histologies who underwent RC between 2004 and 2019 were reanalyzed by two independent radiologists in a blinded review process. Specificity, sensitivity, and accuracy for LN staging as well as LN characteristics were evaluated. Correlation with survival was investigated by Kaplan–Meier method, log-rank test and multivariate analysis.

Results

1361 patients with primary tumor of the bladder underwent RC, of which 163 (12%) patients revealed variant histologies. 65 (47.8%) patients have shown an urothelial variant (UV) and 71 (52.2%) a non-urothelial variant (NUV). LN metastases were found in 18 (27.7%) patients with UV and 21 (29.6%) patients with NUV. The accuracy to detect LN metastasis for all variant histologies was 62% with a sensitivity of 46% and a specificity of 70%. Subgroups of UV and NUV revealed an accuracy of 67% and 57%. An increased number of regional LN (HR 2.8; 1.34–6.18) and the loss of fatty hilum (HR 0.36, 0.17–0.76) were prognostic parameters. In multivariate analysis, a fatty hilum (HR 0.313, 0.104–0.945) and the presence of lymph node metastases (HR 2.866, 1.140–7.207) were prognostic.

Conclusion

This first study on CT morphological behavior of variant histologies revealed an accuracy of UV and NUV comparable to UC with low specificity for all variant histologies. CT scan prior RC should be interpreted in regard to histological subtypes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-022-04010-6.

Expression and Prognostic Implication of PD-L1 in Patients with Urothelial Carcinoma with Variant Histology (Squamous Differentiation or Micropapillary) Undergoing Radical Cystectomy

The expression and prognostic role of programmed death ligand-1 (PD-L1) on tumor-infiltrating immune cells (TICs) has not been determined in urothelial carcinoma (UC) with variant histology. We retrospectively reviewed 90 patients (44 with micropapillary variant of UC (MPUC) and 46 with UC with squamous differentiation (UCSD)) who underwent radical cystectomy between January 2013 and December 2019. The expression of PD-L1 in TICs was measured using the VENTANA (SP-142) immunohistochemistry assay and dichotomized using a 5% cutoff value (positive ≥ 5%). Kaplan–Meier survival analysis was used to estimate recurrence-free survival (RFS), and multivariable Cox proportional hazard models were used to identify factors predicting tumor recurrence. Overall, positive PD-L1 expression in TICs was confirmed in 50 of 90 (55.6%) patients (40.1% (18/44) of MPUC and 69.9% (32/46) of UCSD). RFS was significantly shorter in patients with positive PD-L1 expression in TICs than in those with negative PD-L1 expression both in MPUC (p = 0.005) and UCSD (p = 0.046). Positive PD-L1 expression in TICs was significantly associated with an increased risk of tumor recurrence in both MPUC (HR = 1.85; 95% CI: 1.323–2.672; p = 0.017) and UCSD (HR = 1.58; 95% CI: 1.162–2.780; p = 0.032). In conclusion, positive PD-L1 expression in TICs was significantly associated with poorer RFS in both MPUC and UCSD patients. Our results support the use of adjuvant immunotherapy in these patients if they test positive for PD-L1 in their TICs.

Molecular and Pharmacological Bladder Cancer Therapy Screening: Discovery of Clofarabine as a Highly Active Compound

BACKGROUND

The heterogeneity of bladder cancers (BCs) is a major challenge for the development of novel therapies. However, given the high rates of recurrence and/or treatment failure, the identification of effective therapeutic strategies is an urgent clinical need.

OBJECTIVE

We aimed to establish a model system for drug identification/repurposing in order to identify novel therapies for the treatment of BC.

DESIGN, SETTING, AND PARTICIPANTS

A collection of commercially available BC cell lines (n = 32) was comprehensively characterized. A panel of 23 cell lines, representing a broad spectrum of BC, was selected to perform a high-throughput drug screen.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Positive hits were defined as compounds giving >50% inhibition in at least one BC cell line.

RESULTS AND LIMITATIONS

Amongst >1700 tested chemical compounds, a total of 471 substances exhibited antineoplastic effects. Clofarabine, an antimetabolite drug used as third-line treatment for childhood acute lymphoblastic leukaemia, was amongst the limited number of drugs with inhibitory effects on cell lines of all intrinsic subtypes. We, thus, reassessed the substance and confirmed its inhibitory effects on commercially available cell lines and patient-derived cell cultures representing various disease stages, intrinsic subtypes, and histologic variants. To verify these effects in vivo, a patient-derived cell xenograft model for urothelial carcinoma (UC) was used. Well-tolerated doses of clofarabine induced complete remission in all treated animals (n = 12) suffering from both early- and late-stage disease. We further took advantage of another patient-derived cell xenograft model originating from the rare disease entity sarcomatoid carcinoma (SaC). Similarly to UC xenograft mice, clofarabine induced subcomplete to complete tumour remissions in all treated animals (n = 8).

CONCLUSIONS

The potent effects of clofarabine in vitro and in vivo suggest that our findings may be of high clinical relevance. Clinical trials are needed to assess the value of clofarabine in improving BC patient care.

PATIENT SUMMARY

We used commercially available cell lines for the identification of novel drugs for the treatment of bladder cancer. We confirmed the effects of one of these drugs, clofarabine, in patient-derived cell lines and two different mouse models, thereby demonstrating a potential clinical relevance of this substance in bladder cancer treatment.

Plasmacytoid urothelial carcinoma of the bladder: MRI features and their association with survival

OBJECTIVES

Plasmacytoid urothelial carcinomas (PUC) of the bladder are rare variants known for diffuse and infiltrative spread, however their magnetic resonance imaging (MRI) features are not well established. We aimed to evaluate MRI features of PUC of the bladder and their association with survival.

METHODS AND MATERIALS

This retrospective single-center study included 41 patients with pathologically-proven bladder PUC of the bladder that underwent pre-treatment MRI between January 2000 and March 2020. Two radiologists reviewed MRIs independently followed by consensus with a third radiologist. On MRI, tumor extent, size, Vesical Imaging-Reporting and Data System (VI-RADS) scores (≥4, muscle-invasive; 5, extravesical extension [EVE]), pelvic peritoneal spread (PPS), hydronephrosis, pelvic adenopathy and clinicopathological factors of age, gender, pathological stage, and treatment type were extracted. Kaplan-Meier curves and Cox proportional-hazards models were used to evaluate association with survival.

RESULTS

Thirty-two men and 9 women (median age 70 years, IQR 64-76) were included. Most were muscle-invasive (n = 30 [73.2%]). On MRI, most tumors were diffuse (n = 28 [68.3%]), >5 cm (n = 30 [73.2%]), VI-RADS 4 to 5 (n = 36 [87.8%]) with features of EVE and (n = 31 [75.6%]) and PPS (n = 25 [61.0%]). Variables associated with survival were: Larger tumors (>5 cm; hazard ratio [HR] = 5.0; 95% confidence interval [CI] 1.6-15.5; P < 0.01), diffuse extent (HR = 4.0; 95% CI 1.4-11.2; P = 0.01), EVE (HR = 4.5; 95% CI 1.5-13.6; P < 0.01), PPS (HR = 3.0; 95% CI 1.2-7.4; P = 0.01), hydronephrosis (HR = 13.7; 95% CI 3.1-60.9; P < 0.01), pathologic stage (≥pT3 vs. pT1; HR = 5.6; 95% CI 1.3-22.0; P = 0.02), and margin positivity (HR = 4.4 [95% CI 1.2-16.4], P = 0.03).

CONCLUSION

PUCs of the bladder are commonly large, diffuse VI-RADS score 4 to 5 tumors with MRI features of EVE and PPS. These features and pathological stage were associated with survival.

News in the classification of WHO 2022 bladder tumors

The fifth-edition of World Health Organization (WHO) Classification of Tumors series for urinary and male genital tract tumors has been published, six years later the fourth-edition. In these years, new treatment approaches have been implemented and new molecular data on urological cancers are known.

Morphology remains the groundwork for taxonomy of the urinary tract tumors. However, a molecular approach to classification of urothelial carcinomas and the management of selected neoplasms with new therapeutic modalities such as immunotherapy are emerging. More data are needed for the application of these advances in routine pathology practice and patient management.

The 2022 World Health Organization (WHO) Classification of Tumors of the Urinary System and Male Genital Organs represents an update in classification on urinary tract tumors. It also offers new insights with regards to the grading of heterogeneous non-invasive urothelial neoplasms, the definition of inverted neoplasms, the grading of invasive urothelial carcinomas, the diversity of morphological appearance of urothelial carcinomas, the definition of precursor lesions and the lineage of differentiation of the tumors.

Bladder Cancer Sample Handling and Reporting: Pathologist's Point of View

The aim of this narrative review is to provide adequate information on handling and reporting of the bladder cancer samples to improve the closely collaboration between pathologists and urologists. The main (but not exclusive) research tool used was PubMed and 87 references were selected and quoted in the text. We have considered handling of biopsies, transurethral resection (TUR), and cystectomy specimens to summarize the different methods of sampling and the related issues. Moreover, we considered and discussed the main prognostic factors, such as histological tumor type, grade, and stage of bladder cancer, that should be described in the pathological report. In addition, critical issues encountered in the interpretation of histological samples were discussed.

Development of nomograms related to inflammatory biomarkers to estimate the prognosis of bladder cancer after radical cystectomy

Background

Bladder cancer is one of the most common carcinomas and it brings about huge social economic burden. There is not a reliable way to predict the prognosis of bladder patients. We develop the nomogram to predict the prognosis of bladder cancer patients.

Methods

A total of 127 bladder cancer patients after radical cystectomy were studied retrospectively. Their clinicopathological data were collected for statistical analysis.

Results

The level of albumin/globulin ratio (AGR), C-reactive protein/albumin ratio (CAR), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) associated with pathological and hematological parameters like T stage and hemoglobin. Furthermore, the AGR was associated with overall survival (OS) and CAR, NLR, and PLR were associated with both OS and progression-free survival (PFS) (P<0.05). The multivariate analysis revealed that tobacco smoking, tumor T stage, M stage, NLR, CAR, and AGR were all independent predictors for OS of patients and tobacco smoking, tumor T stage, NLR, CAR, and AGR were independent predictors for PFS of patients. In addition, AGR, CAR, and NLR, as well as, the clinicopathological parameters in the development of nomograms with a C index of 0.901 (95% CI: 0.505-1.269) for OS, and 0.807 (95% CI: 0.755-0.858) for PFS. The nomograms were able to provide a prognosis of the OS with the area under the curve (AUC) =0.86. Further, tests assessed the PFS with the AUC =0.84.

Conclusions

This study demonstrates that the nomograms of the inflammatory biomarkers were able to predict prognosis of bladder cancer patients after radical cystectomy.

Bladder cancer histological variants: which parameters could predict the concordance between transurethral resection of bladder tumor and radical cystectomy specimens?

Introduction

The concordance rate of bladder cancer (BCa) histological variants (HV) between transurethral resection of bladder tumor (TURBT) and radical cystectomy (RC) is sub-optimal and is unclear which factors may influence it. The aim of this study was to identify factors that may be correlated to a higher TURBT-RC concordance rate.

Material and methods

Consecutive patients who had undergone RC between 2000 and 2019 at a single Institution with pathological evidence of HV were included. Patients with diagnosis of HV both at RC and at the previous TURBT were enlisted in the TURBT-RC Concordance Group (CG), whereas patients with only evidence of HV at RC in the TURBT-RC Non-Concordance Group (NCG). Surgical factors evaluated were the source of energy (mono- vs bipolar), surgeon’s experience (</≥100), execution of re-TURBT, number and size of specimens at TURBT.

Results

A total of 81 patients were included, 49 (60.5%) in the CG and 32 (39.5%) in the NCG. Among the surgical factors, maximal core length (MCL) was significantly higher in the CG (12.5 vs 10 mm, p = 0.014) (Table 1). At uni- and multivariable analyses, MCL>10 mm represented an independent predictor of concordance [OR 2.95; CI (1.01–8.61); p = 0.048]. Tumor recurrence, focality and dimension, source of energy, surgeon’s experience, performance of re-TURBT and total number of specimens at TURBT did not significantly predict the concordance.

Conclusions

Longer specimens at TURBT yield a higher chance to detect HV before RC. In this light, improving the quality of bladder resection means improving the management of BCa.

Proteomics as a Complementary Technique to Characterize Bladder Cancer

Simple Summary

Although immunohistochemistry is a routine technique in clinics, and genomics has been rapidly incorporated, proteomics is a step behind. This general situation is also the norm in bladder cancer research. This review shows the contributions of proteomics to the molecular classification of bladder cancer, and to the study of histopathology due to tissue insults caused by tumors. Furthermore, the importance of proteomics for understanding the cellular and molecular changes as a consequence of the therapy of bladder cancer cannot be neglected.

Abstract

Bladder cancer (BC) is the most common tumor of the urinary tract and is conventionally classified as either non-muscle invasive or muscle invasive. In addition, histological variants exist, as organized by the WHO-2016 classification. However, innovations in next-generation sequencing have led to molecular classifications of BC. These innovations have also allowed for the tracing of major tumorigenic pathways and, therefore, are positioned as strong supporters of precision medicine. In parallel, immunohistochemistry is still the clinical reference to discriminate histological layers and to stage BC. Key contributions have been made to enlarge the panel of protein immunomarkers. Moreover, the analysis of proteins in liquid biopsy has also provided potential markers. Notwithstanding, their clinical adoption is still low, with very few approved tests. In this context, mass spectrometry-based proteomics has remained a step behind; hence, we aimed to develop them in the community. Herein, the authors introduce the epidemiology and the conventional classifications to review the molecular classification of BC, highlighting the contributions of proteomics. Then, the advances in mass spectrometry techniques focusing on maintaining the integrity of the biological structures are presented, a milestone for the emergence of histoproteomics. Within this field, the review then discusses selected proteins for the comprehension of the pathophysiological mechanisms of BC. Finally, because there is still insufficient knowledge, this review considers proteomics as an important source for the development of BC therapies.

A candidate antineoplastic herbal agent for bladder cancer: Ankaferd Blood Stopper

BACKGROUND AND AIMS

Ankaferd Blood Stopper (ABS) was used for in vitro studies of osteosarcoma and colon carcinoma cancer cell lines to reveal the apoptotic and antineoplastic effects. The aim of this study is to evaluate the antineoplastic effect of ABS on bladder cancer cell cultures.

METHODS

We prospectively collected minimum 0.5 cm parts of fresh frozen tumour samples from patients with bladder tumour from 2015 to 2017. Primary bladder cancer cultures were produced from the frozen tumour samples. Two different doses of ABS were used on cancer cell cultures. Viability tests of each cell cultures were performed. Flow cytometry was used for the determination of apoptosis and necroptosis. We also checked the effect of ABS on different stages, grade and variant histology of bladder cancer cells. The results of all cancer cell cultures were compared with their own controls.

RESULTS

This study included 24 patients. Mean age of patients was 66.2 ± 11.7 years (34-83 years), where 19 of them (79.5%) were males and five (20.5%) were females. When we compared the data, we found decreased cancer cell viability ratio in each ABS group compared with their own controls. Necroptosis was observed in the great majority of ABS groups, and necroptosis and apoptosis were observed in some cell cultures.

CONCLUSIONS

In this study, we demonstrated the cytotoxic effect of ABS on bladder cancer cells. The results of this study suggests planning of animal model of bladder cancer for ABS with intravesical application as an antineoplastic agent. In the future, ABS may be a candidate intravesical treatment agent for bladder cancer.

Single-Cell Proteomic Analysis Dissects the Complexity of Tumor Microenvironment in Muscle Invasive Bladder Cancer

Simple Summary

The tumor microenvironment (TME) is considered to play a key role in the development of many types of tumors. Muscle invasive bladder cancer (MIBC), which is well known for its heterogeneity, has a highly complex TME. Herein, we integrated mass cytometry and imaging mass cytometry to systematically investigate the complexity of the MIBC TME. Our investigation revealed tumor and immune cells with diverse phenotypes. We identified a specific cancer stem-like cell cluster (ALDH⁺PD-L1⁺ER-β⁻), which is associated with poor prognosis and highlighted the importance of the spatial distribution patterns of MIBC TME components. The present study comprehensively elucidated the complexity of the MIBC TME and provides potentially valuable information for future research.

Abstract

Muscle invasive bladder cancer (MIBC) is a malignancy with considerable heterogeneity. The MIBC tumor microenvironment (TME) is highly complex, comprising diverse phenotypes and spatial architectures. The complexity of the MIBC TME must be characterized to provide potential targets for precision therapy. Herein, an integrated combination of mass cytometry and imaging mass cytometry was used to analyze tumor cells, immune cells, and TME spatial characteristics of 44 MIBC patients. We detected tumor and immune cell clusters with abnormal phenotypes. In particular, we identified a previously overlooked cancer stem-like cell cluster (ALDH⁺PD-L1⁺ER-β⁻) that was strongly associated with poor prognosis. We elucidated the different spatial architectures of immune cells (excluded, infiltrated, and deserted) and tumor-associated collagens (curved, stretched, directionally distributed, and chaotic) in the MIBC TME. The present study is the first to provide in-depth insight into the complexity of the MIBC TME at the single-cell level. Our results will improve the general understanding of the heterogeneous characteristics of MIBC, potentially facilitating patient stratification and personalized therapy.

MiR-10a-5p: A Promising Biomarker for Early Diagnosis and Prognosis Evaluation of Bladder Cancer

Introduction

MiRNAs play a critical role in carcinogenesis, among which miR-10a-5p has been reported in several types of human cancer. Nevertheless, the role of miR-10a-5p remain uncovered in bladder cancer (BCa).

Methods

We recruited 88 BCa patients and 36 healthy controls (HC) to form the training cohort, and other 120 BCa patients to form the validation cohort. The clinical samples were collected for analysis. The expression level of miR-10a-5p was evaluated using RT-qPCR. Receiver operating characteristic (ROC) curves were utilized to calculate diagnostic accuracy. Survival curves were generated to analyze survival outcomes. CCK-8 and transwell assays were conducted to test the cell proliferation, migration, and invasion capacities.

Results

MiR-10a-5p was upregulated in human BCa tissues and closely associated with advanced clinicopathological features, including advanced tumor grade, histological grade, and T stage. High expression of miR-10a-5p was associated with worse survival outcomes in BCa patients. Circulating plasma miR-10a-5p expression had the great performance power to discriminate BCa patients form HC patients before surgery, and to differentiate muscle invasive bladder cancer (MIBC) from non-muscle invasive bladder cancer (NMIBC). In addition, overexpression of miR-10a-5p could promote BCa cell proliferation, migration, and invasion.

Conclusion

This study indicates that miR-10a-5p is a crucial diagnostic and prognostic biomarker for BCa patients, and miR-10a-5p exerted a tumor promoting role during BCa cell progression.

Survival benefit of chemotherapy in a contemporary cohort of metastatic urachal carcinoma

BACKGROUND

We relied on the most contemporary Surveillance, Epidemiology, and End Results (SEER) database and tested the hypothesis that chemotherapy may improve survival in metastatic urachal carcinoma (m-UraC).

MATERIAL AND METHODS

Within the SEER database (2004-2016), we identified m-UraC patients aged ≥ 18 years. Propensity score matching (PSM: cystectomy status, age and sex), Kaplan-Meier plots, cumulative incidence plots, Cox regression models and competing risks regression (CRR) models addressed overall mortality (OM) and cancer-specific mortality (CSM).

RESULTS

Overall, 274 m-UraC patients were identified with a median age of 70 years. Most were male (66%) and Caucasian (72%). Overall, 32% received chemotherapy. Chemotherapy-exposed patients were younger (62 vs. 73 years, p<0.001) and more frequently underwent cystectomy (19 vs. 8%, P = 0.014). In 274 m-UraC patients, median OM and CSM were 6 (4 -10) months and 8 (6 -14) months, respectively. After 1:1 PSM, chemotherapy-exposed patients exhibited lower OM (median 16 vs. 3 months; multivariable HR 0.38, P <0.001) and lower CSM (median 17 vs. 4 months; multivariable CRR HR 0.52, P = 0.001). The association between chemotherapy and better survival was even stronger in younger (≤70 years) patients (OM HR: 0.23, P <0.001; CSM CRR HR: 0.42, P = 0.001), but not in older (≥71 years) patients (OM HR: 0.61, P = 0.2; CSM CRR HR: 1.02, P = 1), after PSM and multivariable adjustments.

CONCLUSION

Overall, we validated the very aggressive nature of UraC, when distant metastases are present, and observed that m-UraC patients exposed to chemotherapy exhibited lower OM and CSM.