What Is the Prognostic and Clinical Importance of Urothelial and Nonurothelial Histological Variants of Bladder Cancer in Predicting Oncological Outcomes in Patients with Muscle-invasive and Metastatic Bladder Cancer? A European Association of Urology Muscle Invasive and Metastatic Bladder Cancer Guidelines Panel Systematic Review

Metastatic Tropism in Urothelial Carcinoma With Variant Histology: A Comprehensive NCDB Analysis

INTRODUCTION

Bladder cancer (BCa) with variant histology (VH) is notably aggressive and not as well studied as pure urothelial carcinoma (UC). The characteristics of variant BCa in the setting of metastatic disease may contribute to treatment response/resistance and subsequent disease progression. In this study, we sought to assess VH's impact on metastasis sites at presentation in metastatic BCa.

METHODS

The National Cancer Database was queried from 2004 to 2019 to analyze cT1-4 cN0-3 cM1 patients with UC and VH BCa. The primary endpoint was the presence of metastasis to different organs. Binomial multivariable logistic regression was performed to determine the impact of VH on metastatic sites while controlling for multiple variables.

RESULTS

Total 6005 eligible patients diagnosed with either UC or VH were included. Patients with small cell histology, the second most common VH, were more likely to have liver metastasis (OR: 4.335) while less likely to have lung metastases (OR: 0.521). Squamous cell carcinoma decreased the odds of bone metastasis (OR: 0.449). Adenocarcinoma increased the odds of lung metastases (OR: 1.690). Micropapillary VH is less likely to metastasize to the lungs (OR: 0.182) but more likely to spread to nonregional lymph nodes (OR: 2.623). Sarcomatoid subtype did not exhibit a statistically significant variation in the odds ratio for any of the metastatic sites.

CONCLUSION

This study comprehensively analyzes the limited research regarding metastatic BCa and VH. Our analysis underscores each subtype exhibiting heterogeneous metastatic tropism. Importantly, these findings illustrate the role of routine somatic gene expression profiling to guide adequate staging and treatment intensification and to offer a foundation for future studies of VH BCa care.

A 2-center review of histopathology of variants of upper urinary tract urothelial carcinoma and their impact on clinical outcomes

INTRODUCTION

Similar to bladder cancer, about one third of upper tract urothelial carcinoma (UTUC) present variant histology (VH). We aim to evaluate the incidence, clinical characteristics and the impact on outcomes of VH in UTUC.

METHODS

We consecutively enrolled 77 patients treated between 2009 and 2022 by radical surgery for UTUC from a secondary and a tertiary referral center. A pathology review of all specimens was performed by 1 independent uropathologist for each center. We compared pure UTUC and UTUC with VH and the accuracy of endoscopic biopsy. Descriptive and comparative analysis was performed to assess the association with clinical characteristics and the Kaplan-Meier estimator to compare outcomes.

RESULTS

Median follow-up after surgery was 51 months. VH was present in 21/77 (28%) patients and 4/21 (19%) patients had multiple variants. The most frequent VH was squamous 12/21 (57%), followed by glandular 7/21 (33%) and micropapillary 3/21 variants (14%). Neuroendocrine carcinoma was present in 2 patients. Nested variant was found in 1 patient. Muscle invasive tumor (≥pT2) was present in 30/56 (54%) patients with pure UTUC and in 18/21 (86%) patients with VH (P < 0.05). Presence of carcinoma in situ was seen in 24/56 (43%) patients with pure UTUC and in 16/21 (76%) with VH (P < 0.05). Cumulative 8/56 (14%) with pure UTUC had a nonintravesical recurrence (6 patients with local and 2 distant recurrence) compared to 8/21 (38%) (3 local, 3 nodal, 2 distant) in the subgroup with VH (P < 0.05). Opposite effect was noted for bladder recurrence: 60% for pure UTUC vs. 29% for tumors with VH (P < 0.05). Review of preoperative endoscopic biopsy did not show the presence of VH in any patients. Differences in outcomes did not reach significance: 3yr-OS 63% vs. 42% (P 0.28) and 3yr-CSS 77% vs. 50% (P 0.7).

CONCLUSION

Almost a third of UTUC present VH. Presence of VH is related to more aggressive tumor characteristics and associated with unfavorable outcomes. Due to a higher rate of extravesical recurrences in UTUC with VH, Follow-up controls should include cross sectional imaging and cystoscopy.

ABO Blood Type and Urinary Bladder Cancer: Phenotype, Genotype, Allelic Association with a Clinical or Histological Stage and Recurrence Rate

Background  Previous research on connection between the ABO blood group and bladder cancer has been based on determining the ABO phenotype. This specific research is extended to the molecular level, providing more information about particular ABO alleles. Aim  To investigate the impact of the ABO blood group genotype or phenotype as a risk factor for urinary bladder cancer. Materials and Methods  In the case-control study, we included 74 patients who underwent surgery for a urinary bladder tumor at the Urology Clinic, Clinical Hospital Centre Zagreb, in 2021 and 2022. The control group comprised 142 asymptomatic and healthy blood donors. ABO genotyping to five basic alleles was done using a polymerase chain reaction with sequence-specific primers. We compared ABO phenotypes, genotypes, and alleles between patients and the healthy controls and investigated their distribution according to the clinical and histological stage and recurrence rate. Results  No statistically significant difference was found among the groups, nor for the observed disease stages in terms of the phenotype and genotype. At the allele level, the results show a significantly lower proportion of malignancy in O1 ( p  < 0.001), A1 ( p  < 0.001), and B ( p  = 0.013), and a lower proportion of metastatic disease in A2 (0%, p  = 0.024). We also found significantly higher proportions of high-grade tumors in patients with O1 (71.4%, p  < 0.001), A1 (70.1%, p  = 0.019), of nonmuscle invasive tumors in patients with O1 (55.1%, p  < 0.001), O2 (100%, p  = 0.045), and recurrent tumors in patients with O1 (70.2%, p  < 0.001) and A1 (74.2%, p  = 0.007) alleles. Conclusion  We did not find an association between the ABO blood group genotype or phenotype as a genetic risk factor for urinary bladder cancer. However, an analysis at the allelic level revealed a statistically significant association between certain alleles of the ABO blood group system and urinary bladder tumors, clinical or histological stage, and recurrence rate, respectively.

European Association of Urology Guidelines on Non-muscle-invasive Bladder Cancer (TaT1 and Carcinoma In Situ)-A Summary of the 2024 Guidelines Update

BACKGROUND AND OBJECTIVE

This publication represents a summary of the updated 2024 European Association of Urology (EAU) guidelines for non-muscle-invasive bladder cancer (NMIBC), TaT1, and carcinoma in situ. The information presented herein is limited to urothelial carcinoma, unless specified otherwise. The aim is to provide practical recommendations on the clinical management of NMIBC with a focus on clinical presentation.

METHODS

For the 2024 guidelines on NMIBC, new and relevant evidence was identified, collated, and appraised via a structured assessment of the literature. Databases searched included Medline, EMBASE, and the Cochrane Libraries. Recommendations within the guidelines were developed by the panel to prioritise clinically important care decisions. The strength of each recommendation was determined according to a balance between desirable and undesirable consequences of alternative management strategies, the quality of the evidence (including the certainty of estimates), and the nature and variability of patient values and preferences.

KEY FINDINGS AND LIMITATIONS

Key recommendations emphasise the importance of thorough diagnosis, treatment, and follow-up for patients with NMIBC. The guidelines stress the importance of defining patients' risk stratification and treating them appropriately.

CONCLUSIONS AND CLINICAL IMPLICATIONS

This overview of the 2024 EAU guidelines offers valuable insights into risk factors, diagnosis, classification, prognostic factors, treatment, and follow-up of NMIBC. These guidelines are designed for effective integration into clinical practice.

Tumor necrosis in magnetic resonance imaging predicts urothelial carcinoma with squamous differentiation in muscle-invasive bladder carcinoma

PURPOSE

This study investigated radiologic features on preoperative MRI to differentiate urothelial carcinoma with squamous differentiation (UCSD) from conventional urothelial carcinoma (UC) in muscle-invasive bladder carcinoma.

METHODS

Ninety-nine patients who underwent radical cystectomy and a preoperative bladder MRI scan within three months before surgery were retrospectively enrolled. Various MRI features, including tumor length, location, multiplicity, long-to-short axis ratio, morphology, radiologic stage, and degree of severe necrosis, were analyzed. Univariable and multivariable logistic regression analyses were performed to identify MRI features predictive of UCSD. The diagnostic performance of a significant MRI feature was assessed using 5-fold cross-validation.

RESULTS

Among the MRI features, significant radiologic findings associated with UCSD in the univariable analysis included heterogeneous tumor signal intensity in T2-weighted images (odds ratio [OR], 3.365; 95% confidence interval [CI], 1.213-9.986; P = 0.022) and contrast-enhanced T1-weighted images (OR, 4.428; 95% CI, 1.519-12.730; P = 0.007), as well as marked (≥ 50%) severe necrosis (OR, 17.100; 95% CI, 4.699-73.563; P < 0.001). In the multivariable analysis, marked (≥ 50%) severe necrosis (odds ratio [OR], 13.755; 95% confidence interval [CI], 2.796-89.118; P = 0.004) was a significant predictor of UCSD. Marked (≥ 50%) severe necrosis showed a high specificity of 95.0% with a precision of 65.0% for diagnosing UCSD based on 5-fold cross-validation.

CONCLUSION

Preoperative bladder MRI revealing marked severe necrosis may be indicative of UCSD and can assist in distinguishing it from conventional UC.

Prognostic impact of histological discordance between transurethral resection and radical cystectomy

OBJECTIVE

To analyse the impact of histological discordance of subtypes (subtypes or divergent differentiation [DD]) in specimens from transurethral resection (TUR) and radical cystectomy (RC) on the outcome of the patients with bladder cancer receiving RC.

PATIENTS AND METHODS

We analysed data for 2570 patients from a Japanese nationwide cohort with bladder cancer treated with RC between January 2013 and December 2019 at 36 institutions. The non-urinary tract recurrence-free survival (NUTR-FS) and overall survival (OS) stratified by TUR or RC specimen histology were determined. We also elucidated the predictive factors for OS in patients with subtype/DD bladder cancer.

RESULTS

At median follow-up of 36.9 months, 835 (32.4%) patients had NUTR, and 691 (26.9%) died. No statistically significant disparities in OS or NUTR-FS were observed when TUR specimens were classified as pure-urothelial carcinoma (UC), subtypes, DD, or non-UC. Among 2449 patients diagnosed with pure-UC or subtype/DD in their TUR specimens, there was discordance between the pathological diagnosis in TUR and RC specimens. Histological subtypes in RC specimens had a significant prognostic impact. When we focused on 345 patients with subtype/DD in TUR specimens, a multivariate Cox regression analysis identified pre-RC neutrophil-lymphocyte ratio and pathological stage as independent prognostic factors for OS (P = 0.016 and P = 0.001, respectively). The presence of sarcomatoid subtype in TUR specimens and lymphovascular invasion in RC specimens had a marginal effect (P = 0.069 and P = 0.056, respectively).

CONCLUSION

This study demonstrated that the presence of subtype/DD in RC specimens but not in TUR specimens indicated a poor prognosis. In patients with subtype/DD in TUR specimens, pre-RC neutrophil-lymphocyte ratio and pathological stage were independent prognostic factors for OS.

Histologic subtypes of non-muscle invasive bladder cancer

The majority of bladder cancers (BCs) are non-muscle invasive BCs (NMIBCs) and show the morphology of a conventional urothelial carcinoma (UC). Aberrant morphology is rare but can be observed. The classification and characterization of histologic subtypes (HS) in UC in BC have mainly been described in muscle invasive bladder cancer (MIBC). However, the currently used classification is applied for invasive urothelial neoplasm and therefore, also valid for a subset of NMIBC. The standard transurethral diagnostic work-up misses the presence of HS in NMIBC in a considerable percentage of patients and the real prevalence is not known. HS in NMIBC are associated with an aggressive phenotype. Consequently, clinical guidelines categorize HS of NMIBC as "(very) high-risk" tumors and recommend offering radical cystectomy to these patients. Alternative strategies for bladder preservation can only be offered to highly selected patients and ideally within clinical trials. Novel treatment strategies and biomarkers have been established MIBC and NMIBC but have not been comprehensively investigated in the context of HS in NMIBC. Further evaluation prior to implementation into clinical practice is needed.

Contemporary survival in metastatic bladder cancer patients: A population-based study

The overall survival (OS) improvement after the advent of several novel systemic therapies, designed for treatment of metastatic urothelial carcinoma of the urinary bladder (mUCUB), is not conclusively studied in either contemporary UCUB patients and/or non-UCUB patients. Within the Surveillance, Epidemiology, and End Results database, contemporary (2017-2020) and historical (2000-2016) systemic therapy-exposed metastatic UCUB and, subsequently, non-UCUB patients were identified. Separate Kaplan-Meier and multivariable Cox regression (CRM) analyses first addressed OS in mUCUB and, subsequently, in metastatic non-UCUB (mn-UCUB). Of 3443 systemic therapy-exposed patients, 2725 (79%) harbored mUCUB versus 709 (21%) harbored mn-UCUB. Of 2725 mUCUB patients, 582 (21%) were contemporary (2017-2020) versus 2143 (79%) were historical (2000-2016). In mUCUB, median OS was 11 months in contemporary versus 8 months in historical patients (Δ = 3 months; p < .0001). After multivariable CRM, contemporary membership status (2017-2020) independently predicted lower overall mortality (OM; hazard ratio [HR] = 0.68, 95% confidence interval [CI] = 0.60-0.76; p < .001). Of 709 mn-UCUB patients, 167 (24%) were contemporary (2017-2020) and 542 (76%) were historical (2000-2016). In mn-UCUB, median OS was 8 months in contemporary versus 7 months in historical patients (Δ = 1 month; p = .034). After multivariable CRM, contemporary membership status (2017-2020) was associated with HR of 0.81 (95% CI = 0.66-1.01; p = .06). In conclusion, contemporary systemic therapy-exposed metastatic patients exhibited better OS in UCUB. However, the magnitude of survival benefit was threefold higher in mUCUB and approximated the survival benefits recorded in prospective randomized trials of novel systemic therapies.

Prognostic impact of variant histology in bladder cancer: Would early and aggressive treatment shift the paradigm?

INTRODUCTION

Bladder cancer (BC) is an increasingly frequent malignancy worldwide. Several variant histologies (VH) have been described in BC with a distinct clinical behavior.

OBJECTIVES

This study aims to assess the prognostic impact of VH in BC, comparing its outcomes to pure urothelial carcinoma PUC in both non-muscle invasive (NMIBC) and muscle-invasive (MIBC) settings.

METHODS

We included patients with primary BC, comparing those with VH with those with PUC, with an age and sex-matched proportion of 1:3, considering stage at diagnosis, recurrence-free, progression-free, and overall survival (OS). A total of 616 patients were included in the study, (460 UC and 151 VH).

RESULTS

After first TURBT, MIBC was present in 99 (64.1%) of patients with VH, and 95 (20.6%) with UC (p<0.001). Concerning NMIBC, we observed higher rates of progression to MIBC amid patients with VH (p=0.009). Nodal involvement (p=0.020) and metastatic disease (p<0.001) were significantly higher within the VH group. A higher OS was observed among patients with NMIBC of PUC (p<0.001). There were no statistically significant differences of metastasis-free survival and OS between VH and UC groups within the MIBC setting.

CONCLUSION

We confirmed that VH presents a more aggressive clinical course compared to PUC. An earlier radical treatment within the NMIBC setting could increase the oncological outcomes of the VH patients.

Development of a prognostic model for long-term survival of young patients with bladder cancer: a retrospective analysis of the SEER Database

OBJECTIVES

This study aims to present the clinical characteristics of young patients with bladder cancer (YBCa), evaluate related risk factors and construct a nomogram based on data acquired from the Surveillance, Epidemiology, and End Results (SEER) Database.

DESIGN

Retrospective analysis of the SEER Database (2004-2015) for primary YBCa.

SETTING AND PARTICIPANTS

Data for YBCa (defined as those aged 40 years or younger) were extracted from the SEER Database, which covers approximately 28% of the US population, using the SEER*Stat software (V.8.4.0.1). A total of 1233 YBCa were identified. Patients were randomly assigned to the training and validation sets. The database included clinicopathological features, demographic information and survival outcomes, such as age, gender, race, year of diagnosis, marital status at diagnosis, primary tumour site, histological type, tumour grade, tumour, node, metastases (TNM) staging, treatment regimen for the primary tumour, cause of death and survival time. A nomogram model was developed using univariate and multivariate analyses. The prediction model was validated using the consistency index (C-index), calibration curve and receiver operating characteristic curve.

PRIMARY OUTCOME MEASURES

3-year, 5-year and 10-year overall survival (OS).

RESULTS

1233 YBCa from 2004 to 2015 were randomly assigned to the training set (n=865) and validation set (n=368). Age, marital status, tumour grade, histological type and TNM staging were included in the nomogram. The C-index of the model was 0.876. The 3-year, 5-year and 10-year OS area under the curve values for the training and validation sets were 0.949, 0.923 and 0.856, and 0.919, 0.890 and 0.904, respectively. Calibration plots showed that the nomogram had a robust predictive accuracy.

CONCLUSIONS

To our knowledge, this is the first study to establish a precise nomogram predicting the 3-year, 5-year and 10-year OS in YBCa based on multivariate analyses. Our nomogram may serve as a valuable reference for future diagnostics and individualised treatments for YBCa. However, external validation is warranted to assess the accuracy and generalisability of our prognostic model.

MRI-based automated machine learning model for preoperative identification of variant histology in muscle-invasive bladder carcinoma

OBJECTIVES

It is essential yet highly challenging to preoperatively diagnose variant histologies such as urothelial carcinoma with squamous differentiation (UC w/SD) from pure UC in patients with muscle-invasive bladder carcinoma (MIBC), as their treatment strategy varies significantly. We developed a non-invasive automated machine learning (AutoML) model to preoperatively differentiate UC w/SD from pure UC in patients with MIBC.

METHODS

A total of 119 MIBC patients who underwent baseline bladder MRI were enrolled in this study, including 38 patients with UC w/SD and 81 patients with pure UC. These patients were randomly assigned to a training set or a test set (3:1). An AutoML model was built from the training set, using 13 selected radiomic features from T2-weighted imaging, semantic features (ADC values), and clinical features (tumor length, tumor stage, lymph node metastasis status), and subsequent ten-fold cross-validation was performed. A test set was used to validate the proposed model. The AUC of the ROC curve was then calculated for the model.

RESULTS

This AutoML model enabled robust differentiation of UC w/SD and pure UC in patients with MIBC in both training set (ten-fold cross-validation AUC = 0.955, 95% confidence interval [CI]: 0.944-0.965) and test set (AUC = 0.932, 95% CI: 0.812-1.000).

CONCLUSION

The presented AutoML model, that incorporates the radiomic, semantic, and clinical features from baseline MRI, could be useful for preoperative differentiation of UC w/SD and pure UC.

CLINICAL RELEVANCE STATEMENT

This MRI-based automated machine learning (AutoML) study provides a non-invasive and low-cost preoperative prediction tool to identify the muscle-invasive bladder cancer patients with variant histology, which may serve as a useful tool for clinical decision-making.

KEY POINTS

• It is important to preoperatively diagnose variant histology from urothelial carcinoma in patients with muscle-invasive bladder carcinoma (MIBC), as their treatment strategy varies significantly. • An automated machine learning (AutoML) model based on baseline bladder MRI can identify the variant histology (squamous differentiation) from urothelial carcinoma preoperatively in patients with MIBC. • The developed AutoML model is a non-invasive and low-cost preoperative prediction tool, which may be useful for clinical decision-making.

Pan-immune-inflammation value as a prognostic tool for overall survival and disease-free survival in non-metastatic muscle-invasive bladder cancer

PURPOSE

To evaluate the association between preoperative pan-immune inflammation value (PIV) and overall survival (OS) and disease-free survival (DFS) in patients who underwent radical cystectomy for non-metastatic muscle-invasive bladder cancer.

METHODS

A total of 119 patients with non-metastatic muscle-invasive bladder cancer who underwent radical cystectomy at our institution between January 2014 and January 2022 were included in this retrospective study. PIV was calculated using the formula (monocyte count × neutrophil count × platelet count)/lymphocyte count. Ideal cut-off values for PIV were determined using ROC curve analysis. Kaplan-Meier analysis was used to evaluate the impact of PIV on survival outcomes.

RESULTS

The mean age of patients was 65 ± 14 years, and the mean follow-up duration was 36 months. The ideal cutoff value for PIV was determined to be 406.29, and a PIV above this value was associated with poorer OS (p < 0.001) (73 months vs. 21 months) and DFS (p = 0.002) (35 months vs 19 months). Higher neutrophil-to-lymphocyte ratio (NLR) values were also associated with poorer OS (p < 0.001) and DFS (p < 0.001), with similar effectiveness to PIV. PIV was found to be significantly more effective than platelet-to-lymphocyte ratio (PLR) and systemic immune inflammation index (SII) in predicting DFS.

CONCLUSION

Preoperative PIV may serve as an independent prognostic factor for OS in patients who undergo radical cystectomy with non-metastatic muscle-invasive bladder cancer. A high PIV value was associated with poorer survival outcomes. Prospective multicenter studies are needed to further validate the relationship between PIV and histopathological features of bladder cancer.

Decoding the basis of histological variation in human cancer

Molecular abnormalities that shape human neoplasms dissociate their phenotypic landscape from that of the healthy counterpart. Through the lens of a microscope, tumour pathology optically captures such aberrations projected onto a tissue slide and has categorized human epithelial neoplasms into distinct histological subtypes based on the diverse morphogenetic and molecular programmes that they manifest. Tumour histology often reflects tumour aggressiveness, patient prognosis and therapeutic vulnerability, and thus has been used as a de facto diagnostic tool and for making clinical decisions. However, it remains elusive how the diverse histological subtypes arise and translate into pleiotropic biological phenotypes. Molecular analysis of clinical tumour tissues and their culture, including patient-derived organoids, and add-back genetic reconstruction of tumorigenic pathways using gene engineering in culture models and rodents further elucidated molecular mechanisms that underlie morphological variations. Such mechanisms include genetic mutations and epigenetic alterations in cellular identity codes that erode hard-wired morphological programmes and histologically digress tumours from the native tissues. Interestingly, tumours acquire the ability to grow independently of the niche-driven stem cell ecosystem along with these morphological alterations, providing a biological rationale for histological diversification during tumorigenesis. This Review comprehensively summarizes our current understanding of such plasticity in the histological and lineage commitment fostered cooperatively by molecular alterations and the tumour environment, and describes basic and clinical implications for future cancer therapy.

International Society of Urological Pathology (ISUP) Consensus Conference on Current Issues in Bladder Cancer. Working Group 2: Grading of Mixed Grade, Invasive Urothelial Carcinoma Including Histologic Subtypes and Divergent Differentiations, and Non-Urothelial Carcinomas

The 2022 International Society of Urological Pathology (ISUP) Consensus Conference on Urinary Bladder Cancer Working Group 2 was tasked to provide evidence-based proposals on the applications of grading in noninvasive urothelial carcinoma with mixed grades, invasive urothelial carcinoma including subtypes (variants) and divergent differentiations, and in pure non-urothelial carcinomas. Studies suggested that predominantly low-grade noninvasive papillary urothelial carcinoma with focal high-grade component has intermediate outcome between low- and high-grade tumors. However, no consensus was reached on how to define a focal high-grade component. By 2004 WHO grading, the vast majority of lamina propria-invasive (T1) urothelial carcinomas are high-grade, and the rare invasive low-grade tumors show only limited superficial invasion. While by 1973 WHO grading, the vast majority of T1 urothelial carcinomas are G2 and G3 and show significant differences in outcome based on tumor grade. No consensus was reached if T1 tumors should be graded either by the 2004 WHO system or by the 1973 WHO system. Because of the concern for underdiagnosis and underreporting with potential undertreatment, participants unanimously recommended that the presence of urothelial carcinoma subtypes and divergent differentiations should be reported. There was consensus that the extent of these subtypes and divergent differentiations should also be documented in biopsy, transurethral resection, and cystectomy specimens. Any distinct subtype and divergent differentiation should be diagnosed without a threshold cutoff, and each type should be enumerated in tumors with combined morphologies. The participants agreed that all subtypes and divergent differentiations should be considered high-grade according to the 2004 WHO grading system. However, participants strongly acknowledged that subtypes and divergent differentiations should not be considered as a homogenous group in terms of behavior. Thus, future studies should focus on individual subtypes and divergent differentiations rather than lumping these different entities into a single clinicopathological group. Likewise, clinical recommendations should pay attention to the potential heterogeneity of subtypes and divergent differentiations in terms of behavior and response to therapy. There was consensus that invasive pure squamous cell carcinoma and pure adenocarcinoma of the bladder should be graded according to the degree of differentiation. In conclusion, this summary of the International Society of Urological Pathology Working Group 2 proceedings addresses some of the issues on grading beyond its traditional application, including for papillary urothelial carcinomas with mixed grades and with invasive components. Reporting of subtypes and divergent differentiation is also addressed in detail, acknowledging their role in risk stratification. This report could serve as a guide for best practices and may advise future research and proposals on the prognostication of these tumors.

How Do Molecular Classifications Affect the Neoadjuvant Treatment of Muscle-Invasive Urothelial Carcinoma?

Despite the significant improvements in the field of oncological treatments in recent decades, and the advent of targeted therapies and immunotherapy, urothelial carcinoma of the bladder remains a highly heterogeneous and difficult-to-treat neoplasm with a poor prognosis. In this context, owing to the new methods of genomic sequencing, numerous studies have analyzed the genetic features of muscle-invasive bladder cancer, providing a consensus set of molecular classes, to identify malignancies that may respond better to specific treatments (standard chemotherapy, immunotherapy, target therapy, local-regional treatment, or combinations) and improve the survival. The aim of the current review is to provide an overview of the current status of the molecular landscape of muscle-invasive bladder cancer, focusing our attention on therapeutic and prognostic implications in order to select the most effective and tailored therapeutic regimen for the individual patient.

MicroRNA-367-3p directly targets RAB23 and inhibits proliferation, migration and invasion of bladder cancer cells and increases cisplatin sensitivity

OBJECTIVES

This study investigated the biological role of miR-367-3p upregulation in bladder cancer and verified the mutual relation between miR-367-3p and RAB23.

MATERIALS AND METHODS

Expression levels of miR-367-3p were determined by RT-qPCR in bladder cancer cell lines and human bladder cancer tissues. The effects of miR-367-3p on proliferation, migration and invasion were evaluated by cell colony formation assays, wound healing assays and trans-well assays, respectively. The effects of miR-367-3p and RAB23 on cisplatin sensitivity of bladder cancer cells were assessed by CCK-8 assay. The expression of its target-RAB23 was determined by western blotting in T24, 5637. Plasmids used in dual-luciferase assays were constructed to confirm the action of miR-367-3p on downstream target-RAB23 in T24 cells. And also, the role of miR-367-3p in tumorigenesis was also confirmed in nude mouse models.

RESULTS

The downregulation of miR-367-3p was observed in human bladder cancer tissues. MiR-367-3p downregulation positively correlated with tumor stage and tumor grade. MiR-367-3p overexpression in T24, 5637 cells suppressed the proliferation, migration, and invasion of bladder cancer cells in vitro while decreasing IC50 values under T24 and 5637 cisplatin treatment conditions. RAB23 was shown to be upregulated in bladder cancer tissues and cell lines. MiR-367-3p directly bound to the 3' UTR of RAB23 in T24 cells. RAB23 was potentially accounted for the aforementioned functions of miR-367-3p. Tumor formation experiments in nude mouse models confirmed that overexpression of miR-367-3p could inhibit tumor growth and invasion in vivo.

CONCLUSIONS

miR-367-3p acts as a tumor suppressor in bladder cancer by downregulating RAB23 signaling. We conjecture that miR-367-3p-mediated downregulation of RAB23 expression may be a new therapeutic strategy for bladder cancer treatment.

Initial management and survival of patients with primary metastatic bladder cancer before the immunotherapy era: a population-based study from Norway

Before immunotherapy became part of the management of metastatic bladder cancer (mBC), systemic anti-cancer treatment comprised primarily of platinum-based chemotherapy. The objective of this study was to describe the characteristics, the initial management, overall survival (OS) and hospitalisations of patients with mBC before 2018 when immunotherapy for mBC was introduced in Norway.  Material and methods: It is a nationwide population-based study of primary mBC patients (diagnosed 2008-16). Descriptive statistics were applied and stratified for four initial management options (≤150 days after BC diagnosis): chemotherapy, major local treatment (cystectomy/pelvic radiotherapy), multimodal treatment (chemotherapy and local) and no anti-cancer treatment beyond transurethral resection of bladder tumour (untreated). Group differences were evaluated by Chi-square and Kruskal-Wallis test; OS was estimated with Kaplan-Meier. Results: Of the 305 patients included, 76 (25%) patients had chemotherapy, 46 (15%) patients had major local treatment, 21 (7%) patients had multimodal treatment and 162 (53%) patients were untreated.  Median OS ranged from 2.3 months (untreated) to 9.8 months (chemotherapy). Patients who received treatment had a higher rate of hospitalisation, with a median stay of three to four times that of untreated patients. Conclusion: Before immunotherapy, more than 50% of patients with primary mBC did not receive any initial anti-cancer therapy and had a poor survival. Patients treated with chemotherapy had inferior median OS compared to those treated with comparable systemic strategies in contemporary trials. Our results provide a basis for future research on treatment and survival after the introduction of immunotherapy for mBC, aiming to improve the care and outcome of patients with mBC.

The Impact of Variant Histology in Patients with Urothelial Carcinoma Treated with Radical Cystectomy: Can We Predict the Presence of Variant Histology?

Considering the divergent biological behaviors of certain histological subtypes of urothelial carcinoma, it would be of great importance to examine the impact of variant histology and to predict its presence in patients with bladder cancer. A single-center cohort study included 459 patients who underwent radical cystectomy for urothelial carcinoma between 2017 and 2021. Patients were followed up with until July 2022. We compared clinical, laboratory, and histopathologic characteristics and the overall survival between patients with pure urothelial carcinoma and variant histologies. Our results showed that the patients with variant histology were older and preoperatively more frequently had hydronephrosis and higher values of leukocytes and neutrophils. Also, we found a significant association between variant histology and an advanced stage of tumor disease, the presence of lymphovascular invasion, positive surgical margins, and metastases in surgically resected lymph nodes. The number of neutrophils was identified as an independent preoperative predictor of the presence of variant histology after a radical cystectomy. The overall survival of the patients with variant histology was significantly lower compared to the patients with pure urothelial carcinoma. According to our results, the presence of variant histology represents a more aggressive form of the disease. Preoperative neutrophil counts may indicate the presence of variant histology of urothelial carcinoma in patients with bladder cancer.

Prognostic impact of variant histologies in urothelial bladder cancer treated with radical cystectomy

OBJECTIVES

To evaluate variant histologies (VHs) for disease-specific survival (DSS) in patients with invasive urothelial bladder cancer (BCa) undergoing radical cystectomy (RC).

MATERIALS AND METHODS

We analysed a multi-institutional cohort of 1082 patients treated with upfront RC for cT1-4aN0M0 urothelial BCa at eight centres. Univariable and multivariable Cox' regression analyses were used to assess the effect of different VHs on DSS in overall cohort and three stage-based analyses. The stages were defined as 'organ-confined' (≤pT2N0), 'locally advanced' (pT3-4N0) and 'node-positive' (pTanyN1-3).

RESULTS

Overall, 784 patients (72.5%) had pure urothelial carcinoma (UC), while the remaining 298 (27.5%) harboured a VH. Squamous differentiation was the most common VH, observed in 166 patients (15.3%), followed by micropapillary (40 patients [3.7%]), sarcomatoid (29 patients [2.7%]), glandular (18 patients [1.7%]), lymphoepithelioma-like (14 patients [1.3%]), small-cell (13 patients [1.2%]), clear-cell (eight patients [0.7%]), nested (seven patients [0.6%]) and plasmacytoid VH (three patients [0.3%]). The median follow-up was 2.3 years. Overall, 534 (49.4%) disease-related deaths occurred. In uni- and multivariable analyses, plasmacytoid and small-cell VHs were associated with worse DSS in the overall cohort (both P = 0.04). In univariable analyses, sarcomatoid VH was significantly associated with worse DSS, while lymphoepithelioma-like VH had favourable DSS compared to pure UC. Clear-cell (P = 0.015) and small-cell (P = 0.011) VH were associated with worse DSS in the organ-confined and node-positive cohorts, respectively.

CONCLUSIONS

More than 25% of patients harboured a VH at time of RC. Compared to pure UC, clear-cell, plasmacytoid, small-cell and sarcomatoid VHs were associated with worse DSS, while lymphoepithelioma-like VH was characterized by a DSS benefit. Accurate pathological diagnosis of VHs may ensure tailored counselling to identify patients who require more intensive management.

Small-cell neuroendocrine tumor of the bladder: Unexpected long-term survival with carboplatin-etoposide therapy in a patient with metastatic stage disease

Neuroendocrine small-cell bladder cancer is an extremely rare and aggressive entity, it constitutes <1% of all bladder malignancies. The small-cell neuroendocrine histological variant has a worse prognosis than the classical subtypes. A case of a 53-year-old female consulting with gross hematuria is presented. Cystoscopy revealed a solid aspect lesion involving the posterior wall and dome that was resected. Histopathological findings showed small-cell pure variant carcinoma, high grade, with lymph, vascular, and perineural infiltration, infiltrating the muscle layer. The extension study made by hole body computed tomography scan, showed evidence of multiple lymph nodes and multiple visceral radiological involvements, with pulmonary, hepatic, and peritoneal implants. More than 10 years later, after receiving nine cycles of carboplatin-etoposide remains in complete remission and without radiological evidence of the disease. This is, to our knowledge, one of the longest disease-free survival cases in metastatic small-cell bladder cancer published nowadays.

Diagnosis, treatment and survival from bladder, upper urinary tract, and urethral cancers: real-world findings from NHS England between 2013 and 2019

OBJECTIVE

We report NHS England data for patients with bladder cancer (BC), upper tract urothelial cancer (UTUC: renal pelvic and ureteric), and urethral cancers from 2013 to 2019.

MATERIALS AND METHODS

Hospital episode statistics, waiting times, and cancer registrations were extracted from NHS Digital.

RESULTS

Registrations included 128 823 individuals with BC, 16 018 with UTUC, and 2533 with urethral cancer. In 2019, 150 816 persons were living with a diagnosis of BC, of whom 113 067 (75.0%) were men, 85 117 (56.5%) were aged >75 years, and 95 553 (91.7%) were Caucasian. Incidence rates were stable (32.7-34.3 for BC, 3.9-4.2 for UTUC and 0.6-0.7 for urethral cancer per 100 000 population). Most patients 52 097 (mean [range] 41.3% [40.7-42.0%]) were referred outside the 2-week-wait pathway and 15 340 (mean [range] 12.2% [11.7-12.6%]) presented as emergencies. Surgery, radiotherapy, chemotherapy, or multimodal treatment use varied with disease stage, patient factors and Cancer Alliance. Between 27% and 29% (n = 6616) of muscle-invasive BCs did not receive radical treatment. Survival rates reflected stage, grade, location, and tumour histology. Overall survival rates did not improve over time (relative change: 0.97, 95% confidence interval 0.97-0.97) at 2 years in contrast to other cancers.

CONCLUSION

The diagnostic pathway for BC needs improvement. Increases in survival might be delivered through greater use of radical treatment. NHS Digital data offers a population-wide picture of this disease but does not allow individual outcomes to be matched with disease or patient features and key parameters can be missing or incomplete.

Alternative splicing in bladder cancer: potential strategies for cancer diagnosis, prognosis, and treatment

Bladder cancer is the most common malignancy of the urinary tract worldwide. The therapeutic options to tackle this disease comprise surgery, intravesical or systemic chemotherapy, and immunotherapy. Unfortunately, a wide number of patients ultimately become resistant to these treatments and develop aggressive metastatic disease, presenting a poor prognosis. Therefore, the identification of novel therapeutic approaches to tackle this devastating pathology is urgently needed. However, a significant limitation is that the progression and drug response of bladder cancer is strongly associated with its intrinsic molecular heterogeneity. In this sense, RNA splicing is recently gaining importance as a critical hallmark of cancer since can have a significant clinical value. In fact, a profound dysregulation of the splicing process has been reported in bladder cancer, especially in the expression of certain key splicing variants and circular RNAs with a potential clinical value as diagnostic/prognostic biomarkers or therapeutic targets in this pathology. Indeed, some authors have already evidenced a profound antitumor effect by targeting some splicing factors (e.g., PTBP1), mRNA splicing variants (e.g., PKM2, HYAL4-v1), and circular RNAs (e.g., circITCH, circMYLK), which illustrates new possibilities to significantly improve the management of this pathology. This review represents the first detailed overview of the splicing process and its alterations in bladder cancer, and highlights opportunities for the development of novel diagnostic/prognostic biomarkers and their clinical potential for the treatment of this devastating cancer type. This article is categorized under: RNA Processing > Splicing Regulation/Alternative Splicing RNA in Disease and Development > RNA in Disease.

Efficacy and safety of transurethral resection of bladder tumour combined with chemotherapy and immunotherapy in bladder-sparing therapy in patients with T1 high-grade or T2 bladder cancer: a protocol for a randomized controlled trial

BACKGROUND

Bladder cancer is the tenth most common cancer worldwide. For patients with T1 high-grade or T2 bladder cancer, radical cystectomy is recommended. However, radical cystectomy is associated with various complications and has a detrimental impact on the quality of life. Bladder-sparing therapy has been widely explored in patients with muscle-invasive bladder cancer, and whether a combination of transurethral resection of bladder tumour (TURBT) with chemotherapy and immunotherapy shows definite superiority over TURBT plus chemotherapy is still a matter of debate. The aim of this study is to investigate the efficacy and safety of TURBT combined with chemotherapy and immunotherapy in bladder-sparing therapy in patients with T1 high-grade or T2 bladder cancer who are unwilling or unsuitable to undergo radical cystectomy.

METHODS

An open-label, multi-institutional, two-armed randomized controlled study will be performed with 86 patients with T1 high-grade or T2 bladder cancer meeting the eligibility criteria. Participants in the experimental group (n = 43) will receive TURBT combined with chemotherapy (GC: gemcitabine 1000 mg/m² on the 1st day and the 8th day, cisplatin 70 mg/m² on the 2nd day, repeated every 21 days) and immunotherapy (toripalimab 240 mg on the 5th day, repeated every 21 days), and those in the control group (n = 43) will receive TURBT plus chemotherapy (GC). The primary outcome is pathological response, and the secondary outcomes include progression-free survival, overall survival, toxicities, and quality of life.

DISCUSSION

To the best of our knowledge, this is the first study to evaluate the efficacy and safety of TURBT combined with GC regimen and toripalimab in bladder-sparing therapy in patients with T1 high-grade or T2 bladder cancer. The expected benefit is that the combination of TURBT with chemotherapy and immunotherapy would be more effective than TURBT plus chemotherapy without compromising the quality of life and increasing the toxicity.

TRIAL REGISTRATION

ChiCTR2200060546, chictr.org.cn, registered on June 14, 2022.

Refining the Characterization and Outcome of Pathological Complete Responders after Neoadjuvant Chemotherapy for Muscle-Invasive Bladder Cancer: Lessons from the Randomized Phase III VESPER (GETUG-AFU V05) Trial

Neoadjuvant cisplatin-based chemotherapy (NAC) followed by radical cystectomy and pelvic lymph node dissection is the optimal treatment for patients with muscle-invasive bladder cancer. In recent years, the VESPER trial showed a statistically significant higher progression-free survival with dd-MVAC (dose dense methotrexate, vinblastine, doxorubicin, and cisplatin) compared to GC (gemcitabine and cisplatin). In the present report, we refine the characterization and outcome of patients whose cystectomy specimens were pathologically free of cancer (pathological complete response, pCR). We confirm that these patients portend a better outcome as compared to patients with invasive disease (≥pT1N0) at cystectomy. Nested variant and lymphovascular invasion were identified as adverse predictive factors of pCR. Progression-free survival probability three years after pCR on cystectomy was about 85%, regardless of the NAC regimen. A lower creatinine clearance and the delivery of less than four cycles were associated with a higher risk of relapse. Predicting the efficacy of NAC remains a major challenge. The planned analysis of molecular subtypes in the VESPER trial could help predict which patients may achieve complete response and better outcome.

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.

HER2 Expression in Bladder Cancer: A Focused View on Its Diagnostic, Prognostic, and Predictive Role

Bladder cancer (BC) is a heterogeneous disease from a molecular, morphological, and clinical standpoint. HER2 is a known oncogene involved in bladder carcinogenesis. Assessing HER2 overexpression as a result of its molecular changes in a routine pathology practice using immunohistochemistry might be a useful adjunct in several scenarios, namely (1) to correctly identify flat urothelial lesions and inverted urothelial lesions in the diagnostic setting; (2) to provide prognostic hints in both non-muscle invasive (NMI) and muscle invasive (MI) tumors, thus supplementing risk stratification tools, especially when evaluating higher-risk tumors such as those with variant morphology; (3) to improve antibody panels as a surrogate marker of BC molecular subtyping. Furthermore, the potential of HER2 as a therapeutic target has been only partly explored so far, in light of the ongoing development of novel target therapies.

Prognostic value of the sarcomatoid component in bladder cancer: A propensity score matching study

Sarcomatoid carcinoma of the bladder is rare, and little is known about the prognostic impact of the proportion of sarcomatoid components of the bladder. The present study aimed to assess the prognostic value of the proportion of sarcomatoid components with regard to death and recurrence rates in patients with bladder cancer (BC), and to validate the worse survival results of sarcomatoid carcinomas of the bladder using propensity score matching. Patients with sarcomatoid carcinoma of the bladder who were treated at the Affiliated Hospital of Qingdao University between August 2010 and May 2021 were included in the study. A 1:2 propensity score matching system based on age, sex and pathological T stage was used for sarcomatoid and non-sarcomatoid carcinoma matching. Finally, 114 patients with BC were included. Patients with sarcomatoid carcinoma had worse 5-year cancer-specific survival (CSS) (69.1 vs. 86.9%; log-rank P=0.008) and recurrence-free survival (RFS) (64.1 vs. 83.6%; log-rank P=0.001) rates compared with patients with non-sarcomatoid carcinoma, as had the subgroup with muscle invasion. Multivariate analysis revealed sarcomatoid carcinoma as an independent prognostic factor. Patients with a low proportion of sarcomatoid components (1-50%) had a better prognosis than patients with a high proportion (>50%), and no significant difference was found compared with the non-sarcomatoid group. Overall, a proportion of sarcomatoid components >50% was a predictor of CSS and RFS. Sarcomatoid components markedly increased the risk of death and recurrence in muscle-invasive BC, but not in non-muscle-invasive BC. A higher proportion of sarcomatoid components was significantly associated with poorer survival.

A model for predicting overall survival in bladder cancer patients with signet ring cell carcinoma: a population-based study

INTRODUCTION

This study is to examine the predictors of survival and to construct a nomogram for predicting the overall survival (OS) of primary bladder signet ring cell carcinoma (SRCC) patients based on the analysis of the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

A total of 219 eligible patients diagnosed with SRCC were analyzed using the 2004-2015 data from SEER database. Univariate and multivariate Cox regression were used to determine independent prognostic factors, followed by development of a nomogram based on the multivariate Cox regression models. The consistency index (C-index), receiver operating characteristic (ROC) curve, and calibration curve were used to validate the prognostic nomogram.

RESULTS

The nomograms indicated appreciable accuracy in predicting the OS, with C-index of 0.771 and 0.715, respectively. The area under the curve (AUC) of the nomogram was 0.713 for 1 year, 0.742 for 3 years, and 0.776 for 5 years in the training set, while was 0.730 for 1 year, 0.727 for 3 years, and 0.697 for 5 years in the validation set. The calibration curves revealed satisfactory consistency between the prediction of deviation correction and ideal reference line.

CONCLUSIONS

The prognostic nomogram developed in the analytical data of SEER it provided high accuracy and reliability in predicting the survival outcomes of primary bladder SRCC patients and could be used to comprehensively assess the risk of SRCC. Moreover, they could enable clinicians to make more precise treatment decisions for primary bladder SRCC patients.

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.

Urothelial Carcinoma: Divergent Differentiation and Morphologic Subtypes

Urothelial carcinoma (UC) is known to encompass a wide spectrum of morphologic features and molecular alterations. Approximately 15% to 25% of invasive UC exhibits histomorphologic features in the form of "divergent differentiation" along other epithelial lineages, or different "subtypes" of urothelial or sarcomatoid differentiation. It is recommended that the percentage of divergent differentiation and or subtype(s) be reported whenever possible. Recent advances in molecular biology have led to a better understanding of the molecular underpinning of these morphologic variations. In this review, we highlight histologic characteristics of the divergent differentiation and subtypes recognized by the latest version of WHO classification, with updates on their molecular and clinical features.

The 2022 ENCR Recommendations on recording and reporting of urothelial tumours of the urinary tract

An updated European Network of Cancer registries (ENCR) Recommendations on Recording and Reporting of Urothelial Tumours of the Urinary Tract had been published in 2022. After the publication by the ENCR of the "Recommendations for coding bladder cancers" in 1995, knowledge about the biology and pathology of urinary tract tumors and their classification has varied and increased substantially. On the other hand, several studies have shown that cancer registries use different definitions, criteria for inclusion and coding of urothelial tumors. This great variability among registries affects not only the criteria for recording (registration, coding and classification) but also the criteria of reporting (counting in the statistics of incidence and survival) urinary tract tumors. This causes difficulties in the data comparability from different registries. Recording and reporting of urothelial tumors requires the application of standard criteria that must take into account the combination of the multiple aspects as the primary topography, the histological type, the grade, the extent of invasion, the multi-centricity, the progressions and the time interval between tumors. This led to the creation of a Working Group of the ENCR that developed these recommendations on the recording and reporting of urothelial tumors of the urinary tract. This article reports these recommendations and the rationale for each.

Differences in Cancer-Specific Mortality after Trimodal Therapy for T2N0M0 Bladder Cancer according to Histological Subtype

We aimed at assessing the impact of non-urothelial variant histology (VH), relative to urothelial carcinoma of the urinary bladder (UCUB), on cancer-specific mortality (CSM) in T2N0M0 bladder cancer patients treated with trimodal therapy (TMT). TMT patients treated for T2N0M0 bladder cancer were identified within the Surveillance, Epidemiology, and End Results database (2000−2018). Patients who underwent TMT received trans-urethral resection of the bladder tumor, chemotherapy, and radiotherapy. CSM-FS rates were tested using Kaplan−Meier plots and multivariable Cox-regression (MCR) models according to histological subtype: UCUB vs. neuroendocrine carcinoma vs. squamous cell carcinoma vs. adenocarcinoma. A total of 3846 T2N0MO bladder cancer patients treated with TMT were identified. Of these, 3627 (94.3%) harbored UCUB, while 105 (2.7%), 85 (2.2%), and 29 (0.8%) harbored neuroendocrine carcinoma, squamous cell carcinoma, and adenocarcinoma, respectively. In Kaplan−Meier analyses, 3-yr CSM-FS rates were 57% for UCUB, 51% for neuroendocrine carcinoma, 35% for squamous cell carcinoma, and 60% for adenocarcinoma (p-value < 0.0001). In MCR models, only squamous cell carcinoma exhibited higher CSM than UCUB (HR 1.98, 95%CI 1.5−2.61, p-value < 0.001). Despite the small number of observations, squamous cell carcinoma distinguished itself from UCUB based on worse survival in T2N0M0 patients after TMT.

French AFU Cancer Committee Guidelines - Update 2022-2024: Non-muscle-invasive bladder cancer (NMIBC)

OBJECTIVE

To update the ccAFU recommendations for the management of bladder tumours that do not infiltrate the bladder muscle (NBMIC).

METHODS

A systematic review (Medline) of the literature from 2020 to 2022 was performed, taking account of the diagnosis, treatment options and surveillance of NMIBC, while evaluating the references with their levels of evidence.

RESULTS

The diagnosis of NMIBC (Ta, T1, CIS) is made after complete full-thickness tumour resection. The use of bladder fluorescence and the indication of a second look (4-6 weeks) help to improve the initial diagnosis. The EORTC score is used to assess the risk of recurrence and/or tumour progression. Through the stratification of patients in low, intermediate and high-risk categories, adjuvant treatment can be proposed: intravesical chemotherapy (immediate postoperative, initiation regimen) or BCG (initiation and maintenance regimen) instillations, or even the indication of cystectomy for BCG-resistant patients.

CONCLUSION

Updating the ccAFU recommendations should contribute to improving patient management, as well as the diagnosis and treatment of NMIBC.

Plasmacytoid Urothelial Carcinoma of the Bladder That Manifests Disseminated Carcinomatosis of the Bone Marrow: A Case Report of Extremely Rapid Progression

Plasmacytoid urothelial carcinoma (PUC) of the bladder is a rare variant of invasive urothelial carcinoma (UC) with aggressive behavior. Despite its prognosis being poorer than that of conventional UC, a median overall survival of approximately 2 years is ensured when it is treated with radical cystectomy (RC), and few patients die within a few months of RC. In this paper, we report the case of a patient with PUC who developed widespread bone metastasis only 6 weeks after RC, which resulted in death within 2 months postoperatively.

Neoadjuvant chemotherapy for muscle-invasive bladder cancer: does variant histology matter?

PURPOSE

The most frequent histology of bladder tumors is urothelial carcinoma. Most are pure urothelial carcinomas (PUC) but up to one-third of the cases present variant histological (VH) features. The aim of this study was to evaluate the role of variant histology in neoadjuvant chemotherapy (NAC) response in patients with urothelial muscle-invasive bladder cancer.

METHODS

We retrospectively analyzed data from 77 patients with bladder cancer who performed neoadjuvant chemotherapy at two institutions.

RESULTS

Complete pathological response (ypT0) was higher in patients with PUC (38.5%), comparing with VH (12%). Logistic regression analysis demonstrated that variant histology is associated with an 89% lesser likelihood of tumor downstaging, with advanced clinical T stages and positive smoking history as independent predictors. The estimated mean cancer-specific survival was 68.91 months for PUC patients and 50.23 months for VH patients (log rank test, P = 0.024). Multivariate Cox regression analysis demonstrated that VH and clinical T stage were independent predictors of cancer-specific survival, indicating a worse outcome for patients with VH and advanced clinical T stages.

CONCLUSIONS

There are only a few retrospective studies evaluating the clinical impact of variant histology tumors, which are mainly managed as PUC. Our results demonstrate that VH is associated with a worse likelihood of tumor downstaging after NAC and a worse cancer-specific survival in bladder cancer patients. There is a need for further studies and genetic analysis to identify the patients most likely to achieve ypT0 status and downstaging after NAC.

Survival trends in chemotherapy exposed metastatic bladder cancer patients and chemotherapy effect across different age, sex, and race/ethnicity

PURPOSE

To test for survival differences in metastatic urothelial carcinoma of the urinary bladder (mUCUB) patients, according to years of diagnosis, age, sex, and race/ethnicity over time and for the effect of chemotherapy on overall mortality (OM).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results (2000-2016), we identified 6860 mUCUB patients. Of those, 3,249 were exposed to chemotherapy. Kaplan-Meier plots and Cox regression models focused on OM. First, we tested the effect of years of diagnosis (historical [2000-2005] vs. intermediate [2006-2011] vs. contemporary [2012-2016]) in chemotherapy exposed mUCUB patients. Second, we tested the effect of chemotherapy in all mUCUB patients.

RESULTS

In chemotherapy exposed mUCUB patients according to historical vs. intermediate vs. contemporary years, median overall survival was 11 vs. 13 vs. 14 months respectively, which translated into hazard ratios (HR) of 0.86 (P = 0.005) and 0.75 (P < 0.001) in intermediate and contemporary vs. historical, respectively. Subgroup analyses in <70 years old, males and Caucasians were in agreement regarding statistically significant differences between historical vs. intermediate vs. contemporary, respectively. In multivariable Cox regression models fitted in the entire mUCUB cohort, chemotherapy exposure reduced OM (HR: 0.46; P < 0.001). Virtually the same results were recorded in age, sex, and race/ethnicity subgroups analyses.

CONCLUSIONS

Contemporary chemotherapy exposed mUCUB patients exhibited better survival than their historical and intermediate counterparts. Chemotherapy reduced mortality by half, across all patient types.

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.

Are We Ready to Implement Molecular Subtyping of Bladder Cancer in Clinical Practice? Part 2: Subtypes and Divergent Differentiation

Following several attempts to achieve a molecular stratification of bladder cancer (BC) over the last decade, a "consensus" classification has been recently developed to provide a common base for the molecular classification of bladder cancer (BC), encompassing a six-cluster scheme with distinct prognostic and predictive characteristics. In order to implement molecular subtyping (MS) as a risk stratification tool in routine practice, immunohistochemistry (IHC) has been explored as a readily accessible, relatively inexpensive, standardized surrogate method, achieving promising results in different clinical settings. The second part of this review deals with the pathological and clinical features of the molecular clusters, both in conventional and divergent urothelial carcinoma, with a focus on the role of IHC-based subtyping.

Oral Preparation of Hyaluronic Acid, Chondroitin Sulfate, Curcumin, and Quercetin (Ialuril® Soft Gels) for the Prevention of LUTS after Intravesical Chemotherapy

Intravesical chemotherapy may cause chemical cystitis and related lower urinary tract symptoms (LUTS). The aims of this study were to evaluate the efficacy and safety of an oral preparation of hyaluronic acid (HA), chondroitin sulfate (CS), curcumin, and quercetin (Ialuril® Soft Gels) to reduce the severity of LUTS in patients with a history of bladder cancer (BCa) undergoing intravesical chemotherapy. We designed a monocentric, randomized, double-blind, placebo-controlled pilot trial. Patients referred to our institute between November 2016 and March 2018 were enrolled. All subjects had non-muscle-invasive BCa and received intravesical chemotherapy with mitomycin C (MMC). Patients were randomized 1:1 in two groups (intervention vs. control). All subjects underwent oral administration (Ialuril® Soft Gels or placebo) starting one week before the first weekly instillation and ending 30 days after the last one, subsequently starting one week before each monthly instillation and ending 14 days after it. International prostate symptom score (IPSS) and 0-100 visual analogue scale (VAS) were used to assess the efficacy of the treatment. Adverse events were also described. Patients were evaluated at baseline and after 1, 4, 7, and 13 months of intravesical chemotherapy. A total of 34 patients were enrolled. The median IPSS score was significantly lower in the intervention group compared to the control group at 4 (13 vs. 17 points; p = 0.038), 7 (10 vs. 18 points; p < 0.001), and 13 (10 vs. 17 points; p = 0.002) months. The median VAS score was significantly lower in the intervention group compared to the control group at 7 (22 vs. 37 points; p = 0.021) and 13 (20 vs. 35 points; p = 0.024) months. No AE specifically related to supplement or placebo was recorded. Oral formulation of HA, CS, quercetin, and curcumin could be an effective and safe supportive therapy against chemical cystitis in patients receiving intravesical chemotherapy for BCa.

Molecular Oncology of Bladder Cancer from Inception to Modern Perspective

Within the last forty years, seminal contributions have been made in the areas of bladder cancer (BC) biology, driver genes, molecular profiling, biomarkers, and therapeutic targets for improving personalized patient care. This overview includes seminal discoveries and advances in the molecular oncology of BC. Starting with the concept of divergent molecular pathways for the development of low- and high-grade bladder tumors, field cancerization versus clonality of bladder tumors, cancer driver genes/mutations, genetic polymorphisms, and bacillus Calmette-Guérin (BCG) as an early form of immunotherapy are some of the conceptual contributions towards improving patient care. Although beginning with a promise of predicting prognosis and individualizing treatments, "-omic" approaches and molecular subtypes have revealed the importance of BC stem cells, lineage plasticity, and intra-tumor heterogeneity as the next frontiers for realizing individualized patient care. Along with urine as the optimal non-invasive liquid biopsy, BC is at the forefront of the biomarker field. If the goal is to reduce the number of cystoscopies but not to replace them for monitoring recurrence and asymptomatic microscopic hematuria, a BC marker may reach clinical acceptance. As advances in the molecular oncology of BC continue, the next twenty-five years should significantly advance personalized care for BC patients.

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.

Head-to-head Intra-individual Comparison of [68Ga]-FAPI and [18F]-FDG PET/CT in Patients with Bladder Cancer

AIM/PURPOSE

Fibroblast activation protein-(FAP)-ligands, a novel class of tracers for PET/CT imaging, demonstrated promising results in previous studies in various malignancies compared to standard [¹⁸F]FDG PET/CT. ⁶⁸Ga-labeled fibroblast activation protein inhibitor-([⁶⁸Ga]Ga-DOTA-FAPI)-PET/CT impresses with sharp contrasts in terms of high tumor uptake and low background noise leading to clear delineation. [¹⁸F]FDG PET/CT has limited accuracy in bladder cancer due to high background signal. Therefore, we sought to evaluate the diagnostic potential of [⁶⁸Ga]FAPI in patients with bladder cancer.

MATERIAL AND METHODS

This retrospective analysis consisted of 8 patients (median age 66), 7 of whom underwent both [⁶⁸Ga]FAPI and [¹⁸F]FDG PET/CT scans with a median time interval of 5 days (range 1-20 days). Quantification of tracer uptake was determined with SUV_max and SUV_mean. Furthermore, the tumor-to-background ratio (TBR) was derived by dividing the SUV_max of tumor lesions by the SUV_max of adipose tissue, skeletal muscle, and blood pool.

RESULTS

Overall, 31 metastases were detected in five patients including lymph node metastases (n = 23), bone metastases (n = 4), lung metastases (n = 3), and a peritoneal metastasis (n = 1). In one patient, [⁶⁸Ga]FAPI demonstrated significant uptake in the primary tumor located in the bladder wall. [⁶⁸Ga]FAPI-PET/CT demonstrated significantly higher uptake compared to [¹⁸F]FDG PET/CT with higher mean SUV_max (8.2 vs. 4.6; p = 0.01). Furthermore, [⁶⁸Ga]FAPI detected additional 30% (n = 9) lesions, missed by [¹⁸F]FDG. TBR demonstrated favorable uptake for [⁶⁸Ga]FAPI in comparison to [¹⁸F]FDG. Significant differences were determined with regard to metastasis/blood pool ([⁶⁸Ga]FAPI 5.3 vs [¹⁸F]FDG 1.9; p = 0.001).

CONCLUSION

[⁶⁸Ga]FAPI-PET/CT is a promising diagnostic radioligand for patients with bladder cancer. This first described analysis of FAP-ligand in bladder cancer revealed superiority over [¹⁸F]FDG in a small patient cohort. Thus, this so far assumed potential has to be confirmed and extended by larger and prospective studies.

A study of the immunohistochemical profile of bladder cancer in neuro-urological patients by the French Association of Urology

PURPOSE

To establish whether the expression of markers of cell differentiation (CK7, CK14, CK20, GATA3), apoptosis (p53), proliferation (Ki67, STAG2) and peri-tumoural lymphocytes (CD3, CD8), provides specific information about urothelial carcinogenesis in neuro-urological patients with bladder cancer (NBC).

METHODS

Tissue samples from NBC were retrieved from 15 centres in France and compared to control samples from non neuro-urological patients with bladder cancer (NNBC) and from neuro-urological patients without bladder cancer (NB). The expression of CK7, CK14, CK20, GATA3, p53, Ki67, STAG2, CD3 and CD8 markers was analysed using immunohistochemistry of tissue microarray sections.

RESULTS

Overall, tissue samples from 124 patients were included in the study (n = 72 NBC, n = 26 NNBC and n = 26 NB). Muscle invasive bladder cancer (MIBC) was found in 52 NBC patients (72.2%) and squamous cell differentiation in 9 (12.5%). In NBC samples, the expression of CK20 and GATA3 was significantly more frequent in NMIBC compared to MIBC (p = 0.015 and p = 0.004, respectively). CK20 and GATA3 were significantly more expressed in NBC compared to NNBC (p < 0.001 and p = 0.010, respectively). The expression of CK14, Ki67, CD3 and CD8 was significantly more frequent in NBC than in NNBC samples (p = 0.005, p < 0.001, p < 0.001 and p < 0.001, respectively). The expression of CD3 and CD8 was similar in NBC and NB samples.

CONCLUSION

In NBC, markers of basal differentiation, proliferation and peri-tumoural lymphocytes were significantly more expressed compared to NNBC controls. These results suggest the aggressiveness of NBC and the role of chronic inflammation in the carcinogenesis of bladder cancer in neuro-urological patients.

Nomograms to predict individual prognosis of patients with primary signet ring cell carcinoma of the urinary bladder

Background

Signet ring cell carcinoma (SRCC) is a rare but highly malignant variant of bladder carcinoma. Nomograms have demonstrated good accuracy in predicting the prognosis and guiding the management of pure urothelial carcinoma (UC). However, no accurate and applicable nomogram has been formulated for primary SRCC cases. This study aimed to determine significant prognostic factors and to construct nomograms for predicting the survival outcomes of patients with primary SRCCs of the urinary bladder.

Methods

A total of 317 eligible patients diagnosed with SRCC were analyzed using the 2004–2016 data from the Surveillance, Epidemiology, and End Results database. Univariate and multivariate analyses were performed to explore the prognostic values. Nomograms were established to estimate the overall survival (OS) and cancer-specific survival (CSS) based on the Cox regression results. The performance of SRCC nomograms was evaluated using the concordance index and calibration curves. Survival curves were applied according to various surgical methods, lymph node status, and risk groups distinguished by nomograms.

Results

Two nomograms included common indicators that were significantly associated with OS and CSS, including T stage, M stage, tumor size, surgery, and the lymph node ratio (LNR). The nomograms indicated appreciable accuracy in predicting the OS and CSS, with concordance index of 0.723 [95% confidence interval (95% CI: 0.692–0.754] and 0.740 (95% CI: 0.701–0.779), respectively. The calibration curves revealed satisfactory consistency between the prediction of deviation correction and ideal reference line.

Conclusions

The two nomograms developed in this study showed high accuracy and reliability in predicting the survival outcomes of patients with SRCC and could be used to comprehensively assess the risk of SRCC. Moreover, they could assist in the optimal treatment selection for such patients.

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.

Plasmacytoid variant urothelial carcinoma of the bladder: effect of radical cystectomy and chemotherapy in non-metastatic and metastatic patients

PURPOSE

Data about optimal management of plasmacytoid (PCV) bladder cancer patients are extremely scarce and limited by sample size. We focused on PCV bladder cancer patients to explore the effect of radical cystectomy (RC) and chemotherapy in non-metastatic (T _2-4N_0-3M₀), as well as in metastatic (T_anyN_anyM₁) subgroups.

METHODS

Using the Surveillance, Epidemiology and End Results database (2000-2016), we identified 332 PCV patients with muscle-invasive disease or higher (≥ T₂N₀M₀). Kaplan-Meier plots and Cox regression models addressed cancer-specific mortality (CSM).

RESULTS

In 332 PCV patients, median age was 68 years (Interquartile range [IQR]:58-76). Of those, 252 were non-metastatic patients (76%) vs 80 were metastatic patients (24%), at presentation. Of non-metastatic patients, 142 (56%) underwent RC and 131 (52%) underwent chemotherapy. Chemotherapy did not improve CSM in non-metastatic PCV. Conversely, RC was associated with lower CSM (hazard ratio [HR]: 0.51, p = 0.002). Median CSM-free survival was 48 vs 38 months for RC treated vs RC not treated. Of metastatic patients, 22 (28%) underwent RC and 42 (52%) underwent chemotherapy. Both chemotherapy and RC improved CSM in metastatic PCV. Median CSM-free survival was 12 vs 7 months for RC treated vs RC not treated (HR: 0.27, p < 0.001). Median CSM-free survival was 11 vs 4 months for chemotherapy exposed vs chemotherapy naïve (HR: 0.32, p = 0.002).

CONCLUSIONS

Although RC resulted in lower CSM, chemotherapy failed to show that effect in non-metastatic PCV patients. Conversely, both chemotherapy and RC resulted in statistically significantly lower CSM in metastatic PCV patients.

piRNAs and PIWI Proteins as Diagnostic and Prognostic Markers of Genitourinary Cancers

piRNAs (PIWI-interacting RNAs) are small non-coding RNAs capable of regulation of transposon and gene expression. piRNAs utilise multiple mechanisms to affect gene expression, which makes them potentially more powerful regulators than microRNAs. The mechanisms by which piRNAs regulate transposon and gene expression include DNA methylation, histone modifications, and mRNA degradation. Genitourinary cancers (GC) are a large group of neoplasms that differ by their incidence, clinical course, biology, and prognosis for patients. Regardless of the GC type, metastatic disease remains a key therapeutic challenge, largely affecting patients’ survival rates. Recent studies indicate that piRNAs could serve as potentially useful biomarkers allowing for early cancer detection and therapeutic interventions at the stage of non-advanced tumour, improving patient’s outcomes. Furthermore, studies in prostate cancer show that piRNAs contribute to cancer progression by affecting key oncogenic pathways such as PI3K/AKT. Here, we discuss recent findings on biogenesis, mechanisms of action and the role of piRNAs and the associated PIWI proteins in GC. We also present tools that may be useful for studies on the functioning of piRNAs in cancers.

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.