The Impact of Squamous and Glandular Differentiation on Survival After Radical Cystectomy for Urothelial Carcinoma

Advances, recognition, and interpretation of molecular heterogeneity among conventional and subtype histology of urothelial carcinoma (UC): a survey among urologic pathologists and comprehensive review of the literature

AIMS

Urothelial carcinoma (UC) demonstrates significant molecular and histologic heterogeneity. The WHO 2022 classification has hinted at adding molecular signatures to the morphologic diagnosis. As morphology and associated molecular repertoire may potentially translate to choices of and response to therapy and relapse rate, broader acceptability of recognizing these key features among uropathologists is needed. This prompted an international survey to ascertain the practice patterns in classical/subtype UC among uropathologists across the globe.

METHODS AND RESULTS

A survey instrument was shared among 98 uropathologists using SurveyMonkey software. Anonymized respondent data were analysed. The response rate was 85%. A majority were in concordance with the profiles of luminal (93%) and basal (82%) types. Opinion on the FGFR3 testing platform was variable. While 95% concurred that TERT promoter mutation is the key driver in UC, 72% had the opinion that APOBEC mutagenesis is the main signature in muscle invasive bladder cancer (MIBC). Uropathologists have divergent opinions on MIBC and ERCC2 mutations. Among the participants, 94% would quantify aggressive micropapillary and sarcomatoid histology, while 88% would reevaluate another transurethral resection of the bladder tumour specimen in nonmuscle invasive tumour with micropapillary, small cell, or sarcomatoid histology. A leading number agreed to specific molecular signatures of micropapillary (93%), plasmacytoid (97%), and small cell (86%) subtypes. Ninety-six percent of participants agreed that a small-cell component portends a more aggressive course and should be treated with neoadjuvant chemotherapy and 63% would perform HER2/neu testing only on oncologist's request in advanced tumours. Ninety percent agreed that microsatellite instability testing, although not a standard protocol, should be considered in young patients with upper tract UC. Eighty-six percent agreed that UC with high tumour mutational burden would be a better candidate for immunotherapy.

CONCLUSION

In the era of precision medicine, enhanced understanding of molecular heterogeneity of UC will contribute to better therapeutic options, novel biomarker discovery, innovative management protocols, and outcomes. Our survey provides a broad perspective of pathologists' perceptions and experience regarding incorporation of histomolecular approaches to "personalize" therapy. Due to variable clinical adoption, there is a need for additional data using uniform study criteria. This will drive generation of best practice guidelines in this area for widespread and consistent clinical utility.

The association between variant histology and prognostic, histomorphological and clinical aspects of bladder urothelial carcinoma

This study underscores the imperative consideration of histological subtypes and divergent differentiation in accurately estimating bladder urothelial carcinoma prognosis and guiding treatment decisions. A comparative analysis was conducted, examining clinical, histological, and prognostic factors between conventional urothelial carcinoma and urothelial carcinoma with variant histology in a clinical sample. A retrospective analysis of slides and other clinicopathologic data was conducted these cases, with an emphasis on key diagnostic elements. We examined 829 cases of urothelial carcinoma of the bladder, comprising of 744 transurethral resection (TUR) and 85 radical cystectomy (RS) specimens, an analysis that showed that 80.5 % (667 cases) were conventional urothelial carcinoma (CUC) and that 19.5 % (162 cases) exhibited variant histology (hereafter "urothelial carcinoma with subtype histology" [UCSH]). TNM classifications for the RS cases were as follows: 2 cases were stage group 0a, 11 stage group 1, 16 stage group 2, 45 stage group 3a, 2 stage group 3b, 1 stage group 4a, and 8 stage group 4b. Only 2 of the RS cases were found to be non-invasive. Among 744 TUR specimens, 387 were found to have a non-invasive tumor whereas 357 had invasive tumors. The most prevalent subtype in the UCSH group was urothelial carcinoma with squamous differentiation, accounting for 54.3 % (88 cases). Notably, 8.02 % (13 cases) exhibited more than one histological subtype. Papillary configuration, histological grade, lamina propria, muscularis mucosa and serosa invasion, lymphovascular invasion, presence of urothelial carcinoma in situ, and overall survival significantly differed between the UCSH and CUC groups (p < 0.05). However, mean age, gender, tumor size, lymphocytic response, disease-free survival, and survival status did not differ significantly (p > 0.05). Among the UCSH group, lower levels of papillary configuration, higher histological grade, higher degree of lamina propria, muscularis mucosa and serosa invasion, and the presence of carcinoma in situ corresponded to higher percentage of histological subtype morphology (p < 0.05). No significant difference in survival status was observed between the groups with and without subtype histology (p = 0.083). This study found that clinical and histopathological prognostic factors associated with a more aggressive disease were linked to the presence and percentage of histological subtypes. Recognizing histological subtype is crucial for treatment decisions and prognosis prediction in urothelial carcinoma cases with these subtypes.

Pathology focused review of morphologic subtypes and molecular variants of urothelial carcinoma with an emphasis on clinical/treatment relevance

Urothelial carcinoma (UC) has significant morbidity, mortality, and remains the most financially costly carcinoma to manage and treat. This review will cover special morphologic features of UC that may be noted by the pathologist and any subsequent significance in terms of clinical management or treatment considerations as mentioned or recommended in the latest WHO 2022 classification of GU tumors. Many important potentially therapy altering morphologic findings can be consistently identified and reported on routine microscopic examination of hematoxylin and eosin (H&E) stained slides. Furthermore, there has been a rapid advancement of molecular diagnostics and tailored therapies throughout oncology, and we will briefly highlight some of these as they relate to the management of UC. We will actively attempt to limit the discussion of histologic descriptions or pathologic diagnostic criteria of these entities and focus rather on the recognition of their importance/implication for clinicians who must make clinical management decisions based upon these findings. Finally, the importance of open lines of communication with the pathologists who review clinical specimens as well as their practice and reporting methods cannot be overstated.

Clinicopathological risk factors associated with tumor relapse of upper tract urothelial carcinoma after radical nephroureterectomy: A single institution 20-year experience

Upper tract urothelial carcinoma (UTUC) is a relatively rare yet aggressive malignancy. While radical nephroureterectomy (RNU) remains the cornerstone treatment, UTUC has high local and metastatic relapse rates, leading to a dismal prognosis. To identify the clinicopathological factors associated with an increased risk of local and metastatic relapse in UTUC, we conducted a retrospective analysis of 133 consecutive UTUC patients who underwent RNU from 1998 to 2018. Patients lost to follow-up or with a history of bladder cancer were excluded from the study. The remaining 87 patients were categorized into two subgroups: those with tumor recurrence/relapse (40 cases) and those without recurrence/relapse (47 cases). Clinical and pathological characteristics were compared across the two groups. Multiple factors are associated with UTUC recurrence/relapse including larger tumor size, histology divergent differentiations/subtypes, high tumor grade, advanced pathologic T stage, positive margin, lymphovascular invasion (LVI), positive lymph node status, and preoperative hydronephrosis. Multivariate Cox regression analysis revealed that squamous differentiation predicted recurrence/relapse (p = 0.012), independent of tumor stage. Moreover, compared to the conventional histology type, UTUC with squamous differentiation had a significantly higher relapse rate (p = 0.0001) and poorer survival (p = 0.0039). This observation was further validated in invasive high-grade UTUC cases. Our findings suggest that many pathological factors contribute to UTUC recurrence/relapse, particularly, squamous differentiation may serve as an independent risk predictor for relapse and a potent prognosticator for adverse cancer-specific survival in UTUC patients. Recognizing and thoroughly assessing the pathological factors is essential for better oncologic management of UTUC.

Urinary tract cytology showing variant morphology and divergent differentiation

Urothelial carcinoma represents a diverse group of tumours with distinct histologic subtypes, each exhibiting unique cytomorphologic features, architectural growth patterns, and/or well-developed aberrant differentiation. In fact, there are more than 13 subtypes of urothelial carcinoma recognized in the 2022 WHO classification of tumours in the urinary tract. The identification of these subtypes is crucial for an accurate diagnosis of urothelial carcinoma, and many have important clinical implications. Variant/divergent features may coexist with conventional high-grade urothelial carcinoma (HGUC) or present with 100% variant morphology. In urinary tract cytology (UTC), urothelial carcinoma can display divergent differentiation, such as squamous, glandular, or small cell carcinoma differentiation. The use of cell block preparations and immunohistochemistry with available residual urine can enhance diagnostic accuracy. On the other hand, identifying urothelial carcinoma variants, including nested, micropapillary, and plasmacytoid subtypes, poses significant challenges in UTC. Many cases of these variants are only detected retrospectively after variant histology has been established from resection specimens. Moreover, some variants exhibit features inconsistent with the diagnostic criteria for HGUC according to the Paris System for Reporting Urinary Tract Cytology. Nevertheless, the rarity of pure variant morphology and the occurrence of some false negatives for these variant cases are essential to maintain the specificity of UTC overall. This review covers the histology, cytomorphology, and important clinical aspects observed in urothelial carcinoma exhibiting divergent differentiation and various urothelial carcinoma variants detected in UTC.

The impact of squamous cell transformation on the prognosis of patients treated with radical nephroureterectomy

BACKGROUND

Limited information is available for guiding the management of upper urinary tract (UUT) urothelial carcinoma with squamous differentiation (UC-SqD). We did not even know about the difference between pure urothelial carcinoma (UC) and UC-SqD in the UUT regardless of treatment policy and prognosis. Instead of direct comparisons against each other, we included the third UUT malignancy, squamous cell carcinoma (SCC). This three-way-race model allows us to more clearly demonstrate the impact of squamous cell transformation on patient outcomes in UUT malignancy.

METHODS

We retrospectively analysed 327 patients with UC, UC-SqD, or SCC who underwent radical nephroureterectomy with bladder cuff excision (RNU) at Taichung Veterans General Hospital, Taichung, Taiwan, between January 2006 and December 2013. A Kaplan-Meier survival analysis was used to evaluate the relationship between patient outcomes and histology. Multivariate Cox proportional hazards modelling was also used to predict patient prognoses.

RESULTS

The five-year postoperative cancer-specific survival (CSS) rates were 83.6% (UC), 74.4% (UC-SqD), and 55.6% (SCC), and the 5-year recurrence-free survival (RFS) rates were 87.7% (UC), 61.5% (UC-SqD), and 51.9% (SCC). UC patients had significantly better 5-year RFS than UC-SqD and SCC patients (P = 0.001 and P < 0.0001, respectively). Patients with pure UC had significantly better 5-year CSS than SCC patients (P = 0.0045). SCC or UC-SqD did not independently predict disease-specific mortality (HR 0.999, p = 0.999; HR 0.775, p = 0.632, respectively) or disease recurrence compared to pure UC (HR 2.934, p = 0.239; HR 1.422, p = 0.525, respectively). Age, lymphovascular invasion (LVI), and lymph node (LN) status independently predicted CSS, while pathological tumour stage, LN status, and LVI predicted RFS.

CONCLUSIONS

SCC and UC-SqD are not independent predictors of survival outcomes in patients with UUT tumours. However, they are associated with other worse prognostic factors. Hence, different treatments are needed for these two conditions, especially for SCC.

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.

Clinicopathologic and Survival After Cystectomy Outcomes in Squamous Cell Carcinoma of the Bladder

BACKGROUND

Squamous cell carcinoma of the bladder (SqCC) is a rare disease with limited management data. Thus, we sought to characterize the clinicopathologic and survival outcomes amongst patients with SqCC and explore the association of squamous differentiation within urothelial carcinoma (UC w/Squam), as compared to muscle invasive pure UC.

METHODS

We conducted a single-center retrospective cohort study of patients, stratified by histology, who underwent cystectomy for MIBC. Baseline clinicopathologic characteristics were compared, and overall survival was assessed using Kaplan-Meier method.

RESULTS

We identified 1,034 patients; 37 (3.58%) with SqCC histology, 908 (87.81%) with UC histology, and 89 (8.61%) with UC w/ Squam histology. Among SqCC patients, a higher proportion were Black and similarly a higher proportion were women; amongst patients with UC w/ Squam a higher proportion had lower BMI; and amongst patients with UC a higher proportion had lower clinical (c) T, cN, pathological (p) T, and pN stages. Patients presenting with UC were more likely to receive intravesical therapy; patients presenting with SqCC were less likely to receive neoadjuvant chemotherapy (NAC). Adjuvant chemotherapy rates were similar. With post-hoc Bonferroni analysis, overall survival, cancer-specific survival, and recurrence-free survival were significantly worse for the UC w/ Squam cohort.

CONCLUSIONS

UC w/ Squam histology was associated with worse survival outcomes after cystectomy for muscle invasive bladder cancer compared to UC. Our results suggest that UC w/ Squam is associated with more advanced disease compared to UC, warranting further prospective work on consideration of combination therapies for patients with this disease state.

[Morphological variants of the invasive urothelial cell carcinoma.]

Urothelial cell carcinoma is the most common malignant tumor of the urinary tract, which develops in the renal pelvis, ureter, and bladder, and rarely it develops in the ureter. Histologically, urothelial cell carcinoma is categorized into non-invasive and invasive forms. Non-invasive urothelial cell carcinoma has papillary growth, it is usually well differentiated, and has a favorable outcome, while invasive urothelial cell carcinoma infiltratively spreads the organs of origin, it is typically poorly differentiated, and often associated with a poor prognosis. In the case of invasive urothelial cell carcinoma, the clinical course is primarily determined by the depth of invasion, but according to recent data, morphological variants of urothelial cell carcinoma respond differently to oncological treatments, and their biological behavior is also distinct. These subtypes and variants are significantly underdiagnosed in Hungary and internationally because the criteria for histological diagnosis are not clear for many subsets. The latest 2022 WHO classification of urinary tract tumors significantly clarified the definitions of various subtypes and variants. In this paper, utilizing the current classification, we review and explain these subtypes' morphological, immunohistochemical, differential diagnostic, prognostic, and predictive characteristics intending to make them appear as much as possible in everyday diagnostic practice. Also, the work aims to present the individual urothelial cell carcinoma subtypes and variants to the Hungarian community of pathologists, oncologists, and urologists, so that the previously high level of urological oncology care can become even more personalized. Orv Hetil. 2023; 164(40): 1567-1582.

Morphology, immunohistochemistry characteristics, and clinical presentation of microcystic urothelial carcinoma: a series of 10 cases

BACKGROUND

Microcystic urothelial carcinoma (MUC) is a rare variant of urothelial carcinoma with histological appearances similar to begin lesions. Thus far, approximately 50 cases have been reported. Here, we investigated the clinicopathological features of MUC.

METHODS

Clinical data and paraffin-embedded tissue blocks were collected. Immunohistochemical staining and polymerase chain reaction-Sanger sequencing were performed to detect the phenotype and TERT mutation status of MUC, respectively.

RESULTS

The mean patient age was 58.8 ± 14.5 years, with a male predominance (8:2). The pathological stage was T1 in one case, T2 in three cases, T3 in four cases, and T4 in two cases. Tumor metastases or death occurred in all five patients who were followed up within 1-3 years. Histological analyses revealed microcystic, tubular, cribriform, and occasionally cord-like structures, which generally lacked interstitial reactions. The lumens were empty, contained eosinophilic secretion, or were filled with mucin. The microcysts/tubules/cribriform patterns were lined by flat, cuboid, signet ring, or columnar types of epithelia. The cuboid, signet ring, and columnar types represented "glandular metaplasia" or glandular differentiation of urothelial carcinoma. Immunohistochemistry analyses revealed distinct co-expression patterns involving the luminal markers FOXA1 and GATA3, as well as the basal markers CK5/6 and CD44. All 10 cases exhibited a luminal phenotype according to the GATA3+/CK14- criterion, whereas nine cases exhibited a luminal phenotype according to the FOXA1+/CK14- criterion. The telomerase reverse transcriptase-C228T mutation was detected in seven cases.

CONCLUSIONS

MUC is a rare variant with a deceptively benign form of urothelial carcinoma, which is generally identified as a late-stage tumor with a poor prognosis. It exhibits distinct co-expression of luminal and basal markers, along with the TERT-C228T mutation.

Recent Advances in the Classification of Bladder Cancer - Updates from the 5th Edition of the World Health Organization Classification of the Urinary and Male Genital Tumors

BACKGROUND

The World Health Organization Classification (WHO) of Urinary and Male Genital Tumors has recently been updated to its 5th edition. The new edition presents a comprehensive approach to the classification of urinary and male genital tumors with an incorporation of morphologic, clinical, and genomic data.

OBJECTIVE

This review aims to update the new classification of bladder cancer in the 5th edition and to highlight important changes in nomenclatures, diagnostic criteria, and molecular characterization, as compared to the 4th edition.

METHODS

The pathologic classification of bladder cancer in the 5th edition of WHO Classification of Urinary and Male Genital Tumours was compared to that in the 4th edition. PubMed was searched using key words, including bladder cancer, WHO 1973, WHO 1998, WHO 2004, WHO 2016, histology, pathology, genomics, and molecular classification in the time frame from 1973 to August of 2022. Other relevant papers were also consulted, resulting in the selection of 81 papers as references.

RESULTS

The binary grading of papillary urothelial carcinoma (UC) is practical, but it may be oversimplified and contribute to "grade migration" in recent years. An arbitrary cutoff (5%) has been proposed for bladder cancers with mixed grades. The diagnosis of papillary urothelial neoplasm with low malignant potential has been dramatically reduced in recent years because of overlapping morphology and treatment with low-grade papillary UC. An inverted growth pattern should be distinguished from true (or destructive) stromal invasion in papillary UC. Several methods have been proposed for pT1 tumor substaging, but it is often challenging to substage pT1 tumors in small biopsy specimens. Bladder UC shows a high tendency for divergent differentiation, leading to several distinct histologic subtypes associated with an aggressive clinical behavior. Molecular classification based on the genomic analysis may be a useful tool in the stratification of patients for optimal treatment.

CONCLUSIONS

The 5th edition of WHO Classification of Urinary and Male Genital Tumours has made several significant changes in the classification of bladder cancer. It is important to be aware of these changes and to incorporate them into routine clinical practice.

Transurethral resection of bladder tumor-based bladder preservation therapy for refractory high risk non-muscle invasive bladder cancer: Current landscape and future directions

Bladder cancer is the most common malignant tumor of urinary system worldwide. Approximately 75% of patients with bladder cancer present with non-muscle-invasive bladder cancer (NMIBC), which is effectively managed with transurethral resection of bladder tumor (TURBT). For refractory high risk NMIBC, patients are typically treated by radical cystectomy (RC). TURBT deserves further evaluation. Growing evidence suggests that repeated TURBT-based bladder-sparing approaches may improve oncological outcomes and quality of life in highly selected patients. Novel imaging techniques and biomarkers may aid in patients selection and postoperative surveillance. With growing interest in adding immunotherapy to refractory bladder cancer, TURBT based approaches enable the bladder preservation therapy for high risk NMIBC. Here we summarize the current landscape, biomarkers for surveillance, and future directions for applying TURBT-based bladder preservation therapy.

Filling the gaps in the research about second primary malignancies after bladder cancer: Focus on race and histology

Purpose

Previous research has shown that bladder cancer has one of the highest incidences of developing a second primary malignancy. So, we designed this study to further examine this risk in light of race and histology.

Patients and methods

Using the surveillance, epidemiology, and end results (SEER) 18 registry, we retrospectively screened patients who had been diagnosed with bladder cancer between 2000 and 2018. We then tracked these survivors until a second primary cancer diagnosis, the conclusion of the trial, or their deaths. In addition to doing a competing risk analysis, we derived standardized incidence ratios (SIRs) and incidence rate ratios (IRRs) for SPMs by race and histology.

Results

A total of 162,335 patients with bladder cancer were included, and during follow-ups, a second primary cancer diagnosis was made in 31,746 of these patients. When the data were stratified by race, SIRs and IRRs for SPMs showed a significant difference: Asian/Pacific Islanders (APIs) had a more pronounced increase in SPMs (SIR: 2.15; p 0.05) than White and Black individuals who had an SIRs of 1.69 and 1.94, respectively; p 0.05. In terms of histology, the epithelial type was associated with an increase in SPMs across all three races, but more so in APIs (IRR: 3.51; 95% CI: 2.11-5.85; p 0.001).

Conclusion

We found that race had an impact on both the type and risk of SPMs. Additionally, the likelihood of an SPM increases with the length of time between the two malignancies and the stage of the index malignancy.

The 2022 World Health Organization Classification of Tumors of the Urinary System and Male Genital Organs-Part B: Prostate and Urinary Tract Tumors

The 2022 World Health Organization (WHO) classification of the urinary and male genital tumors was recently published by the International Agency for Research on Cancer. This fifth edition of the WHO "Blue Book" offers a comprehensive update on the terminology, epidemiology, pathogenesis, histopathology, diagnostic molecular pathology, and prognostic and predictive progress in genitourinary tumors. In this review, the editors of the fifth series volume on urologic and male genital neoplasms present a summary of the salient changes introduced to the classification of tumors of the prostate and the urinary tract.

Gender and Advanced Urothelial Cancer: Outcome, Efficacy and Toxicity following Chemotherapy

Background and Objectives: The incidence of urothelial cancer in males is higher than in females; however, females have a higher risk of recurrence and progression. The aim of our study was to report the effect of gender on the oncological outcome in advanced urothelial cancer. Materials and Methods: In our retrospective study, all patients had undergone primary surgical treatment for urothelial cancer and were affected by stage IV disease at the time of chemotherapy. Response to therapy and toxicity were evaluated. Subgroups were analyzed for tumour presentation, first- and second-line treatment response, progression-free survival (PFS) and overall survival (OS). Results. Seventy-five patients, 18 (24%) females and 57 (76%) males, were considered. Investigation into the distribution of individual characteristics according to gender revealed a significant difference only for smoking, with a prevalence of smokers in women (p = 0.029). At the end of follow-up, OS was higher in females (27.5% vs. 17.4%; p = 0.047). Smoking did not significantly influence OS (p = 0.055), while univariate Cox regression analysis confirmed that males had a higher risk of death (HR = 2.28, 95% CI 0.99–129 5.25), with borderline statistical significance (p = 0.053). Men showed higher PFS than women both after first-line (p = 0.051) and second-line chemotherapy (p = 0.018), with a lower risk of progression (HR = 0.29, 95% CI 0.10–0.86; p = 0.026). No differences were found between genders with regard to toxicity. Conclusions. In our series, PFS rates following first- and second-line therapies for advanced urothelial carcinoma confirmed that females have a greater risk of progression than males.

Overview of histologic variants of urothelial carcinoma: current trends and narrative review on treatment outcomes

Background and Objective

The histologic variants of urothelial carcinoma (UC) are tumors arising from within the urothelium in which some component of the tumor morphology is other than urothelial. They are underdiagnosed, aggressive and have varying pathologic response rates to systemic chemotherapy. There are no consensus guidelines on the use of systemic chemotherapy in variant histology (VH) of UC. We performed a contemporary review on pathologic response rates to neoadjuvant systemic therapy and survival outcomes following radical cystectomy in order to provide a rationale for clinical practice recommendations on the management of UC with VH.

Methods

A PubMed literature search was conducted for all English articles from inception reporting either pathological response rates to neoadjuvant treatment or survival outcomes after radical cystectomy in non-metastatic VH of UC.

Key Content and Findings

Neoadjuvant chemotherapy (NAC) prior to radical cystectomy was shown to be a beneficial treatment strategy in UC with VH. The micropapillary, plasmacytoid, nested and sarcomatoid histologic variants were associated with worse survival outcomes compared to conventional UC and UC with squamous or glandular differentiation despite initial downstaging with chemotherapy. There is evidence of improved survival in patients with sarcomatoid differentiation receiving NAC compared to RC alone. The major prognostic factors that affect survival outcomes in VH of UC include histologic variant subtype, patient age, presence of lymphovascular invasion, hydronephrosis, nodal metastasis and advanced T stage at diagnosis. Recent studies demonstrate that VH of UC are heterogenous tumors and responsiveness to NAC may be a function of the molecular subtypes present.

Conclusions

Based on these findings, NAC to achieve pathologic downstaging prior to radical cystectomy is recommended for MIBC with VH. Biomarkers identified by molecular profiling with immunohistochemistry will need to be validated as predictors of response to NAC in future trials.

T1 bladder carcinoma with variant histology: pathological features and clinical significance

The aim of the study was to stratify high-grade T1 (HGT1) bladder urothelial carcinoma into risk categories based on the presence of variant histology when compared to conventional urothelial carcinoma. The clinicopathological features of 104 HGT1 cases of urothelial carcinoma of the bladder with variant histology present in 34 (37%) were assessed. The endpoint of the study was disease-free survival and cancer-specific survival. Overall, variant histology was identified as a significant predictor of disease-free survival (P = 0.035). The presence of any specific variant histology (squamous, glandular, micropapillary, nested, microcystic, inverted growth, villous-like, basaloid, and lymphoepithelioma-like) was identified as a significant predictor of disease-free survival (P = 0.008) and cancer-specific survival (P = 0.0001) in HGT1 bladder cancer. Therefore, our results support including micropapillary HGT1 urothelial carcinoma within the aggressive high-risk category, as suggested by some recent clinical guidelines, but also favor nested, glandular, and basaloid to be placed in the high-risk category due to their potential of aggressive, life-threatening behavior and their limited response to bacillus Calmette-Guerin therapy. Conversely, the low-risk category would include urothelial carcinomas with squamous, inverted growth, or microcystic morphology, all with limited life-threatening potential and good response to current therapy. A very low-risk category would finally include patients whose tumors present villous-like or lymphoepithelioma-like morphology. In conclusion, our findings support the value of reporting the variant histology as a feature of variable aggressiveness in HGT1 urothelial carcinoma of the bladder.

Squamous cell and urothelial carcinomas in an ileal neobladder

Introduction

In cases of ileal neobladder following radical cystectomy for the treatment of bladder cancer, tumor development in the isolated gut segment is extremely rare. Herein, we report a case of squamous cell and urothelial carcinomas in the ileal neobladder 23 years after radical cystectomy.

Case presentation

A 71‐year‐old man was referred to our hospital for further examination of a solitary tumor in an ileal neobladder. At the age of 48 years, he underwent radical cystectomy with ileal neobladder reconstruction. Transurethral resection of the bladder tumor was performed, and histopathological findings showed squamous cell carcinoma with high‐grade urothelial carcinoma.

Conclusion

To our knowledge, this is the first report of squamous cell and urothelial carcinomas in an ileal neobladder. While secondary tumor development in an ileal neobladder is rare, it is a cause for concern as a late postoperative adverse event. Therefore, long‐term follow‐ups are recommended.

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.

The Significance of Squamous Histology on Clinical Outcomes and PD-L1 Expression in Bladder Cancer

Objectives. To compare the clinicopathologic characteristics of urothelial carcinoma (UC), urothelial carcinoma with squamous differentiation (UCSD), and squamous cell carcinoma (SCC) of the bladder, which have been suggested to differ in terms of risk factors, immunophenotype, and prognosis. Methods. We evaluated the clinicopathologic features of radical cystectomy specimens between 1980 and 2015 with a diagnosis of SCC, UCSD, and UC. PD-L1 immunohistochemistry (clinically available clones 22C3, SP142, and SP263) was performed on SCC and UCSD. Multivariate Cox regression was used to identify prognostic factors. Kaplan-Meier curves were plotted to assess cancer-specific survival (CSS). Results. Of the 1478 cases, there were 1126 UC (76%), 217 UCSD (15%), and 135 SCC (9%). Bladder cancer was more common in men than women (80% vs 20%, P < .0001). However, a higher proportion of SCC and UCSD occurred in women (SCC-36%, UCSD-22%, UC-18%). Women were significantly more likely to be never smokers in all 3 cohorts (UC: 45% vs 16%, UCSD: 44% vs 12%, SCC: 40% vs 18%, P < .0001). Patients with SCC and UCSD were at a higher pathologic stage (>pT2) at the time of cystectomy (UCSD-74%, SCC 71%, UC-44%, P < .0001) and had worse CSS compared to patients with UC (P = 0.006). SCC had higher PD-L1 scores (all clones) than UCSD (P < .0001). PD-L1 22C3 (P = .02, HR: 0.36) and SP142 scores (P = .046, HR: 0.27) predicted CSS on Kaplan-Meier analysis for SCC cases. Conclusions. UC, UCSD, and SCC are associated with different risk factors, gender distributions, and clinical outcomes. PD-L1 is expressed in SCC and UCSD, suggesting some patients may benefit from targeted therapy.

Oncologic Outcomes of Squamous Cell Carcinoma Versus Urothelial Carcinoma With Squamous Differentiation After Radical Cystectomy for Bladder Carcinoma

INTRODUCTION

In this study we aim to compare clinicopathological characteristics and cancer specific survival between patients treated with radical cystectomy for pure squamous cell carcinoma (SCC) and urothelial carcinoma with squamous differentiation (SqD).

PATIENTS AND METHODS

We reviewed data of 1737 consecutive patients treated with radical cystectomy and urinary diversion between January 2004 and February 2014. Only patients with pure SCC or SqD were included in the analysis. Squamous differentiation was defined as intercellular bridges or keratinization in the tumor. Clinicopathological data and recurrence free survival (RFS) were compared between patients diagnosed with SCC and SqD.

RESULTS

SCC and SqD were found in 318 and 223 patients, respectively. Mean age was 57 ± 8.3 years in SCC and 58.8 ± 7.8 in SqD (P = .008). A higher proportion of female patients was observed in SCC group compared to SqD (31.8% vs. 22% P < .0001). Patients with SqD were more likely to have extravesical (58.3% vs. 46.2%: P = .006) and nodal positive disease (34.5% vs. 14.5%: P < .0001) than pure SCC patients. Bilharzial eggs were found in 61% of SCC vs. 46% of SqD (P = .001).; The median (IQR) follow up period for SCC and SqD was 63 (12-112) months and 23 months (9-74.7), respectively. The 5-year RFS for SCC and SqD were 77% and 59.8 %, respectively (P < .0001).; Multivariate cox regression analysis identified advanced pT stage (OR: 1.9, 95% CI: 1.3-2.86, P = .0001), nodal positive disease (OR: 1.6, 95% CI: 1.1-2.48, P = .01) and SqD histology (OR: 1.6, 95% CI: 1.14-2.31, P = .007 as independent predictors of 5-year RFS.

CONCLUSION

Patient with SCC had significantly higher 5-year RFS in comparison to SqD. The higher rate of extravesical disease and lymph node metastasis in SqD patients is indicative of aggressive behavior of this histologic type.

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.

Updated pathology reporting standards for bladder cancer: biopsies, transurethral resections and radical cystectomies

Aim

Optimal management of bladder cancer requires an accurate, standardised and timely pathological diagnosis, and close communication between surgeons and pathologists. Here, we provide an update on pathology reporting standards of transurethral resections of the bladder and cystectomies.

Methods

We reviewed recent literature, focusing on developments between 2013 and 2021.

Results

Published reporting standards developed by pathology organizations have improved diagnosis and treatment. Tumor sub-staging and subtyping has gained increased attention. Lymph nodes continue to be an area of debate, and their staging has seen minor modifications. Several tasks, particularly regarding specimen preparation (“grossing”), are not yet standardized and offer opportunity for improvement. Molecular classification is rapidly evolving, but currently has only limited impact on management.

Conclusion

Pathological reporting of bladder cancer is continuously evolving and remains challenging in some areas. This review provides an overview of recent major developments, with a particular focus on published reporting standards.

Evaluation of the Extent of Variant Histology in Urothelial Carcinoma as a Predictive Marker of Clinical Outcomes After Radical Cystectomy

BACKGROUND/AIM

This study investigated the impact of the extent of variant histology (VH) on the prognosis of patients with bladder cancer (BC).

PATIENTS AND METHODS

We retrospectively evaluated consecutive patients with muscle-invasive BC who were treated with radical cystectomy (RC) at our institution between 2005 and 2018. Recurrence-free survival (RFS) and overall survival (OS) rates were evaluated using Kaplan-Meier analysis and Cox regression.

RESULTS

We identified 103 and 47 patients with pure urothelial carcinoma (UC) and a VH in UC, respectively. At the cutoff of 80%, univariate analysis identified significant differences in RFS (p=0.046) and OS (p=0.038) between patients with ≥80% VH (n=21) and those with <80% VH (n=26). Multivariate analysis revealed that the presence of ≥80% VH was significantly associated with RFS and OS.

CONCLUSION

The presence of ≥80% VH in UC could be an independent predictor of recurrence and mortality after RC.

Expression of Nectin-4 in Bladder Urothelial Carcinoma, in Morphologic Variants, and Nonurothelial Histotypes

The antibody-drug conjugate enfortumab-vedotin acts by targeting nectin-4, a protein that is nearly ubiquitously expressed in conventional urothelial cancer. However, expression of nectin-4 in morphologic variants of urothelial carcinoma and nonurothelial histotypes was unknown. Immunohistochemistry for nectin-4 using was performed on 169 patients including 83 with nonmuscle invasive bladder cancer and 86 patients with muscle invasive bladder cancer. Staining was scored for intensity (0 to 3) and extent (% positive cells) using the histological score system, where >15 was considered positive. Overall, 72/83 (87%) samples of nonmuscle invasive urothelial carcinoma were positive, including 29/30 (97%) noninvasive papillary urothelial carcinomas, 7/8 (87.5%) carcinomas in situ, 36/45 (80%) papillary urothelial carcinomas invading the lamina propria. Overall, 50/86 muscle invasive tumors were positive, including 15/22 (68.2%) urothelial carcinomas, 7/10 (70%) squamous cell carcinomas, 3/11 (28%) micropapillary tumors, 4/6 (66%) adenocarcinomas, 2/4 (50%) nested carcinomas, 5/8 (63%) plasmacytoid, 1/10 (10%) sarcomatoid carcinomas, and 0/15 (0%) small cell carcinomas. Whole transcriptome RNA sequencing revealed that compared with conventional urothelial carcinomas, most sarcomatoid carcinomas and all but 2 small cell carcinomas expressed very low levels of nectin-4 mRNA but expressed significant levels of either trop2 or ERBB2, which are the molecular targets of 2 other antibody-drug conjugates-sacituzumab gavitecan (trop2) or trastuzumab deruxtecan (ERBB2/HER2). In summary, our study demonstrates that there is heterogeneity of expression of nectin-4 in morphologic variants of urothelial cancer and nonurothelial histotypes, and suggests that testing expression of nectin-4 should be considered in morphologic variants or nonurothelial histotypes found to have lower expression.

Non-Muscle Invasive Bladder Cancer with Variant Histology: Biological Features and Clinical Implications

BACKGROUND

The most common bladder cancer (BC) histotype is pure urothelial carcinoma (UC), which may undergo divergent differentiation in some cases. Variant histology (VH) presents along variable morphologies, either single or combined between them or with pure UC. From a clinical standpoint, the vast majority of BC is diagnosed at non-invasive or minimally invasive stages, namely as non-muscle invasive BC (NMIBC). There is a wide range of therapeutic options for patients with NMIBC, according to their clinical and pathological features. However, current risk stratification models do not show optimal effectiveness. Evidence from the literature suggests that VH has peculiar biological features, and may be associated with poorer survival outcomes compared to pure UC.

SUMMARY

In order to describe the biological features and prognostic/predictive role of VH in NMIBC, and to discuss current treatment options, we performed a systematic literature search through multiple databases (PubMed/Medline, Google Scholar) for relevant articles according to the following terms, single and/or in combination: "non-muscle invasive bladder cancer," "variant histology," "micropapillary variant," "glandular differentiation," "squamous differentiation," "nested variant," "plasmacytoid variant," and "sarcomatoid variant." We extracted 99 studies including original articles, reviews, and systematic reviews, and subsequently analyzed data from 16 studies reporting on the outcome of NMIBC with VH. We found that the relative rarity of these forms as well as the heterogeneity in study populations and therapeutic protocols results in conflicting findings overall. Key Messages: The presence of VH should be taken into account when counseling a patient with NMIBC, since it may upgrade the disease to high-risk tumor and thus warrant a more aggressive treatment.

The prognostic value of cytokeratin and extracellular collagen expression in urinary bladder cancer

BACKGROUND

Expression levels of collagens have been implicated in the progression of various cancers and interact with cytokeratins, but are not well studied in bladder cancer (BC). Therefore, we analyzed the gene and protein expression levels of collagen 1A1 (Col1a1/COL1A1), collagen 3A1 (col3a1/COL3A1), collagen 5A2 (col5a2/COL5A2), cytokeratin 14 (krt14/CK14), and cytokeratin 17 (krt17/CK17) in urothelial BC samples of different stages.

METHODS

In total, 102 fresh frozen and 190 formalin fixed and paraffin embedded (FFPE) samples were tested using immunohistochemistry and RT-qPCR. Expression levels were correlated to clinicopathological and follow-up data.

RESULTS

Col1a1, col3a1, col5a2 and krt14 mRNA levels were significantly overexpressed in high-grade and muscle-invasive BC (MIBC) compared to low-grade and non-muscle invasive BC (NMIBC) cases. Disease-specific survival (DSS) was shorter in patients with high expression levels of col1a1 (p = 0.004), col3a1 (p = 0.004), and col5a2 (p = 0.028). CK14 (p = 0.020), COL3A1 (p = 0.006) and Col5A2 (p = 0.006) protein expression levels were significantly higher and protein expression levels of CK17 (p = 0.05) significantly lower in MIBC compared to NMIBC. Furthermore, CK14 (p = 0.002) and COL5A2 (p = 0.006) protein expressions were significantly higher in high-grade compared to low-grade BC. DSS was shorter in patients with high expression levels of COL5A2 (p = 0.033) and CK14 (p = 0.042).

CONCLUSION

Expression changes of collagens and cytokeratins are univariable prognostic markers in BC.

Squamous differentiation is a potential biomarker predicting tumor progression in patients treated with pembrolizumab for urothelial carcinoma

Immune checkpoint inhibitor (ICI) is widely used and highly effective for some cancer patients but may result in disease progression in others. Hyperprogressive disease in particular is characterized by an acceleration of tumor growth during ICI therapy and has been reported in patients including those with urothelial carcinoma. Biomarkers predicting treatment efficacy are crucial to avoid tumor progression and unnecessary adverse effects. This study aims to clarify the predictors of disease progression for ICI treatment in patients with urothelial carcinoma. We analyzed the response pattern of 23 urothelial carcinomas treated with pembrolizumab and its association with pathological features and potential immunohistochemical markers including EGFR, MDM2, p53, p16, and programmed cell death ligand-1 (PD-L1) expression and CD8- and CD204-positive cell infiltration. During ICI therapy, 13 (57 %) patients showed progressive disease including 6 (26 %) with hyperprogressive disease. Notably, squamous differentiation combined with MAC387 expression was observed exclusively in cases with progressive disease (6 of 13, 46 %); it was not present in cases with stable disease or partial/complete response (0 of 10, p = 0.0019). All tumors with squamous differentiation showed positive staining for EGFR. Additionally, the loss of p16 expression occurred more frequently in cases with progressive disease (8 of 13, 62 %) than in other cases (3 of 10, 30 %), but this finding did not reach statistical significance. Squamous differentiation was also significantly associated with shorter overall survival. Based on our observations, squamous differentiation may be a novel biomarker for predicting disease progression in patients with urothelial carcinoma who receive pembrolizumab.

Stratifying risk for multiple, recurrent, and large (≥3 cm) Ta, G1/G2 tumors in non-muscle-invasive bladder cancer

Purpose

The current stratification of risk groups regarding recurrence and progression of non-muscle-invasive bladder cancer (NMIBC) is problematic. We aimed to assess the long-term outcome and risk of multiple, recurrent, and large (≥3 cm) Ta, G1/G2 tumors after transurethral resection of the bladder tumor (TURBT).

Materials and Methods

We categorized 1,621 patients with NMIBC who underwent TURBT into four risk groups according to the European Association of Urology (EAU) guidelines as follows: low-risk, intermediate-risk, high-risk, and study group. The overall, cancer-specific, disease recurrence-free, and disease progression-free survival rates were estimated by using the Kaplan–Meier method. Then, the impact of risk group was assessed by using a multivariable Cox regression model.

Results

The study group comprised 52 patients (3.2%) within a mean follow-up of 64.8 months. The disease recurred and progressed in 41 (78.8%) and 7 (13.5%) patients, respectively. Among the four groups, the study group showed the highest risk for 10-year recurrence after TURBT. The disease progression risk in the study group was between that of the intermediate- and high-risk groups. Cancer-specific and all-cause deaths occurred in one and four patients in the study group, respectively. The study group had a higher risk for disease recurrence than did the high-risk group; however, it did not have a higher risk for disease progression than in the high-risk group.

Conclusions

Multiple, recurrent, and large (≥3 cm) Ta, G1/G2 tumors carry a higher risk for disease recurrence, but not progression, than in the EAU high-risk group of NMIBC.

Current Management of Localized Muscle-Invasive Bladder Cancer: A Consensus Guideline from the Genitourinary Medical Oncologists of Canada

BACKGROUND: Despite recent advances in the management of muscle-invasive bladder cancer (MIBC), treatment outcomes remain suboptimal, and variability exists across current practice patterns. OBJECTIVE: To promote standardization of care for MIBC in Canada by developing a consensus guidelines using a multidisciplinary, evidence-based, patient-centered approach who specialize in bladder cancer. METHODS: A comprehensive literature search of PubMed, Medline, and Embase was performed; and most recent guidelines from national and international organizations were reviewed. Recommendations were made based on best available evidence, and strength of recommendations were graded based on quality of the evidence. RESULTS: Overall, 17 recommendations were made covering a broad range of topics including pathology review, staging investigations, systemic therapy, local definitive therapy and surveillance. Of these, 10 (59% ) were level 1 or 2, 7 (41% ) were level 3 or 4 recommendations. There were 2 recommendations which did not reach full consensus, and were based on majority opinion. This guideline also provides guidance for the management of cisplatin-ineligible patients, variant histologies, and bladder-sparing trimodality therapy. Potential biomarkers, ongoing clinical trials, and future directions are highlighted. CONCLUSIONS: This guideline embodies the collaborative expertise from all disciplines involved, and provides guidance to further optimize and standardize the management of MIBC.

Pathological and Survival Outcomes Associated with Variant Histology Bladder Cancers Managed by Cystectomy with or without Neoadjuvant Chemotherapy

PURPOSE

Although neoadjuvant chemotherapy is associated with a survival advantage in pure urothelial, muscle invasive bladder cancer, the role of neoadjuvant chemotherapy is less clear in variant histology or urothelial carcinoma with divergent differentiation. We compared chemotherapy response and survival outcomes of patients with nonpure urothelial carcinoma histology who were managed with neoadjuvant chemotherapy followed by cystectomy vs cystectomy alone.

MATERIALS AND METHODS

We analyzed 768 patients with clinical muscle invasive bladder cancer (cT2-4N0M0) who were treated with cystectomy at a tertiary care center from 2007 to 2017. Patients were stratified by histology and treatment strategy. Adjusted logistic and Cox regression models were used to evaluate pathological downstaging, cancer specific survival and overall survival.

RESULTS

The cohort consisted of 410 patients (53%) with pure urothelial carcinoma, 185 (24%) with urothelial carcinoma with divergent differentiation and 173 (23%) with variant histology. Overall, 314 patients (41%) received neoadjuvant chemotherapy prior to cystectomy. There were similar rates of complete (18% to 30%) and partial (37% to 46%) pathological downstaging with neoadjuvant chemotherapy across all histological subgroups (p=0.30 and p=0.40, respectively). However, while patients with pure urothelial carcinoma experienced an overall survival benefit (HR 0.71, 95% CI 0.51-0.98, p=0.0013) and those with variant histology experienced a cancer specific survival benefit (HR 0.55, 95% CI 0.30-0.99, p=0.0495) with neoadjuvant chemotherapy, patients with urothelial carcinoma with divergent differentiation did not experience overall or cancer specific survival benefits with the use of neoadjuvant chemotherapy prior to cystectomy.

CONCLUSIONS

Among patients with muscle invasive bladder cancer those with nonpure urothelial carcinoma histology with variant histology achieved nearly equivalent response rates and survival benefits with the use of neoadjuvant chemotherapy as those with pure urothelial carcinoma, while patients with urothelial carcinoma with divergent differentiation experienced significantly worse survival outcomes regardless of the use of neoadjuvant chemotherapy prior to cystectomy.

Luteolin suppresses bladder cancer growth via regulation of mechanistic target of rapamycin pathway

Luteolin is a natural flavonoid with strong anti–oxidative properties that is reported to have an anti–cancer effect in several malignancies other than bladder cancer. In this study, we describe the effect of luteolin on a human bladder cancer cell line, T24, in the context of the regulation of p21, thioredoxin‐1 (TRX1) and the mechanistic target of rapamycin (mTOR) pathway. Luteolin inhibited cell survival and induced G2/M cell‐cycle arrest, p21 upregulation and downregulation of phospho(p)‐S6, which is downstream of mTOR signaling. Luteolin also upregulated TRX1 and reduced intracellular reactive oxygen species production. In a subcutaneous xenograft mouse model using the rat bladder cancer cell line, BC31, tumor volumes were significantly decreased in mice orally administered luteolin compared to control. Immunohistochemical analysis revealed that increased p21 and decreased p‐S6 expression were induced in the luteolin treatment group. Moreover, in another in vivo N‐butyl‐N‐(4‐hydroxybutyl) nitrosamine (BBN)‐induced rat bladder cancer model, the oral administration of luteolin led to a trend of decreased bladder tumor dimension and significantly decreased the Ki67‐labeling index and p‐S6 expression. Furthermore, the major findings on the metabolism of luteolin suggest that both plasma and urine luteolin‐3ʹ‐O‐glucuronide concentrations are strongly associated with the inhibition of cell proliferation and mTOR signaling. Moreover, a significant decrease in the squamous differentiation of bladder cancer is attributed to plasma luteolin‐3ʹ‐glucuronide concentration. In conclusion, luteolin, and in particular its metabolized product, may represent another natural product‐derived therapeutic agent that acts against bladder cancer by upregulating p21 and inhibiting mTOR signaling.

The applicability and utility of immunohistochemical biomarkers in bladder pathology

Urinary bladder specimens are frequently encountered in the daily practice of surgical pathologists. The spectrum of pathologic entities encountered in bladder specimens is extraordinarily broad, and in some instances, immunohistochemical stains are used to help characterize challenging bladder lesions. Cost-effective biomarker selection tailored to the differential diagnosis facilitates an accurate diagnosis. This comprehensive review is prepared as a reference guide for the use of immunohistochemistry to categorize primary and secondary bladder neoplasms and to evaluate metastatic cancers for possible bladder origin.

Tissue Profile of CDK4 and STAT3 as Possible Innovative Therapeutic Targets in Urinary Bladder Cancer

Bladder cancer represents a global health problem. It ranks ninth in worldwide cancer incidence. In Egypt, carcinoma of the bladder is the most prevalent cancer, Bladder cancer has the highest recurrence rate of any malignancy. Certainly, suitable molecular diagnostic markers are required to improve the early detection of bladder cancer and then to prolong survival of patients. The present study was aimed to explore the expression of CDk4 and STAT3 in bladder cancer tissues as prospective for target therapy. Our studied groups showed higher values of CDK4 and STAT3 expression in malignant tissues (SCC andUC collectively) compared to cystitis, however, significantly higher values of CDK4 and STAT3 expression were detected in UC group compared to SCC group. Urothelial carcinomas with papillary patterns showed lower parameters of CDK4 and STAT3 expression compared to the non-papillary variant, with significant differences. Higher grades of UC showed significantly higher parameters of CDK4 and STAT3 expression compared to low grade ones. Muscle invasion increases the level of CDK4 and STAT3 expression parameters, compared to non-muscle invasive UC.

Slingshot homolog-1 expression is a poor prognostic factor of pT1 bladder urothelial carcinoma after transurethral resection

Objective

Slingshot homolog-1 (SSH-1) shows an important role in the occurrence and development in various tumors. While, the expression and prognostic implications of SSH-1 in bladder urothelial carcinoma (UC) remain unclear and thus were addressed in this study.

Methods

Immunohistochemistry (IHC) was performed on tissue microarrays composed of 624 bladder UC specimens after transurethral resection of bladder tumor (TUR-BT) to detect SSH-1 expression. The clinic-pathological features were compared between SSH-1( +) and SSH-1(−) subgroups. The Kaplan–Meier curve with log-rank test and univariate/multivariate Cox regression model with stepwise backward elimination methods were performed for survival analyses.

Results

In this study, 359 (57.53%) specimens were detected with SSH-1 expression. SSH-1 positivity was significantly associated with higher pathological grade (p = 0.020), lymphovascular invasion (p = 0.006), tumor recurrence (p < 0.001) and progression (p < 0.001) in bladder UC. Besides, SSH-1 positivity predicted a shorter overall survival (OS, p = 0.024), recurrence-free survival (RFS, p < 0.001), progression-free survival (PFS, p = 0.002) and cancer-specific survival (CSS, p = 0.047). Multivariate Cox proportional hazard analysis showed that tumor size (p = 0.007), lymphovascular invasion (p = 0.003), recurrence (p < 0.001), progression (p < 0.001) and SSH-1 expression (p = 0.015) were predictors of poor prognosis in bladder UC patients.

Conclusions

SSH-1 expression was associated with undesirable clinic-pathological characteristics and poor post-operative prognosis in bladder UC patients. SSH-1 might play an important role in bladder UC and serve as a promising predictor of oncological outcomes in patients with bladder UC.

Clinicopathologic analysis of upper urinary tract carcinoma with variant histology

We report on the clinicopathologic features of 115 cases of high-grade urothelial carcinoma of the upper urinary tract with variant histology present in 39 (34%). Variant histology was typically seen in high pathological stage (pT2-pT4) (82%, 32 cases) patients with lower survival rate (70%, 27 cases, median survival 31 months) and consisted in urothelial with one (23%), two (3%), and three or more variants (3%); 4% of cases presented with pure variant histology. Squamous divergent differentiation was the most common variant (7%) followed by sarcomatoid (6%) and glandular (4%), followed by 3% each of micropapillary, diffuse-plasmacytoid, inverted growth, clear cell glycogenic, or lipid-rich. The pseudo-angiosarcomatous variant is seen in 2%, and 1% each of nested, giant-cell, lymphoepithelioma-like, small-cell, trophoblastic, rhabdoid, microcystic, lymphoid-rich stroma, or myxoid stroma/chordoid completed the study series. Loss of mismatch repair protein expression was identified in one case of upper urinary tract carcinoma with inverted growth variant (3.6%). Variant histology was associated to pathological stage (p = 0.007) and survival status (p = 0.039). The univariate survival analysis identified variant histology as a feature of lower recurrence-free survival (p = 0.046). Our findings suggest that variant histology is a feature of aggressiveness in urothelial carcinoma of the upper urinary tract worth it to be reported.

Current Status and Future Perspectives of Immunotherapy for Locally Advanced or Metastatic Urothelial Carcinoma: A Comprehensive Review

Advancements in the understanding of tumor immunology in urothelial carcinoma (UC) have led to U.S Food and Drug Administration (FDA) approval of five novel anti-programmed cell death protein-1/ligand 1 (PD-1/L1) checkpoint inhibitors. In 2017, the anti-PD-L1 antibody atezolizumab and the anti-PD-1 antibody pembrolizumab gained approval for use in cisplatin-ineligible patients with locally advanced and metastatic UC. These approvals were based on single-arm trials, IMvigor210 (atezolizumab) and KEYNOTE-052 (pembrolizumab). Since then, additional checkpoint inhibitors, including avelumab, durvalumab, and nivolumab, have gained approval. Preliminary results suggest additional benefits with combinations of these agents in both first- and subsequent-line therapies, inferring a paradigm shift in the future treatment approach in advanced UC. Ongoing clinical trials will investigate how to utilize predictive biomarkers for optimal patient selection and to incorporate immunotherapy into earlier lines of multimodal treatment. In this comprehensive review, we summarize the evidence supporting the use of checkpoint inhibitors for patients with UC, and highlight ongoing clinical trials that are investigating novel combinations of immunotherapy in various disease settings.

Trends in the use of neoadjuvant chemotherapy for bladder cancer with nonurothelial variant histology: An analysis of the National Cancer Database

Introduction

The aim of this study is to evaluate the trends in the use of neoadjuvant chemotherapy (NAC) over time (2006-2014) for patients diagnosed with muscle-invasive bladder cancer (MIBC) with nonurothelial variant histology (NUVH) in the National Cancer Database.

Materials and Methods

We queried the NCDB for patients with muscle-invasive (i.e. cT2-4N0-3M0/X) urothelial carcinoma (UC) of the bladder. We examined demographic, clinical, and pathologic features associated with NAC, also substratifying into pure UC and NUVH. Tests of association were performed using Chi-square/Fisher's exact test for categorical variables and t-tests, ANOVA, or Kruskal-Wallis test for continuous variables. Outcomes were examined with Cox proportional hazards and 90-day mortality with the Kaplan-Meier method.

Results

Totally 22,320 patients met our inclusion criteria, of whom 22.6% received NAC. The proportion of NAC increased significantly over time in the neuroendocrine and urothelial cell categories with 57.1% and 34.1% of patients in 2014 receiving NAC vs. 44% and 10.6% in 2006. No other variant histology showed a significant increase across the time sampled. Patients receiving NAC were more likely to have downstaging to pT0 (13.4% vs. 2.7%), negative surgical margin (89.1% vs. 86%), and pN0 (63.2% vs. 60.5%) and were less likely to have 30-day (1.4% vs. 3%) or 90-day (5% vs. 8.3%) mortality. Rates of downstaging to pT0 after NAC were similar among histologies.

Conclusion

Neoadjuvant chemotherapy utilization continues to slowly increase in patients with MIBC. Patients with variant histology lag behind in terms of receiving NAC but appear to derive as much benefit as patients with pure urothelial cell bladder cancer.

Impact of squamous differentiation on intravesical recurrence and prognosis of patients with upper tract urothelial carcinoma

Background

The prognostic role of squamous differentiation in upper urinary tract urothelial carcinoma (UTUC) is still unclear. This article describes the impact of squamous differentiation on prognosis and intravesical recurrence of patients with primary UTUC treated with radical nephroureterectomy (RNU).

Methods

Totally, we retrieved (I) 669 histologically confirmed UTUC patients without histologic variants; (II) 101 UTUC patients with squamous differentiation in our institution, dating from April 2003 to April 2016. The clinical pathological characteristics and survival outcomes were compared between these two cohorts.

Results

In our study, 13% UTUC patients were detected with squamous differentiation. The mean age of all the patients examined was 66, of whom 70% were males. Squamous differentiation significantly associated with tumor stage, tumor grade and lymphovascular invasion. The Kaplan-Meier and Cox regression analyses showed that presence of squamous differentiation was correlated with shorter cancer specific survival of UTUC patients. The 5-year cancer specific survival rates were 47% for squamous differentiation-present patients and 63% for squamous differentiation-absent patients. UTUC patients with squamous differentiation showed a higher frequency of high-grade disease in advanced stage (pT2/pT3/pT4), while the discrepancy was not shown in early stage (pTa/pT1). Intravesical recurrence was observed in 27% patients. We found that intravesical recurrence had little impact on the cancer specific survival of squamous differentiation-present patients, yet it tended to decrease cancer specific survival among squamous differentiation-absent patients.

Conclusions

The presence of squamous differentiation in UTUC patients was a vital prognostic factor for cancer specific survival and correlated with intravesical recurrence after receiving RNU.

Clinical Significance of Squamous Differentiation in Urothelial Carcinoma of the Bladder

The prognostic value of squamous differentiation (SD) in urothelial carcinoma (UC) of the bladder is unclear. The aim of this study was to identify the clinical significance of SD in UC in terms of oncological outcomes in patients undergoing radical cystectomy (RC). We evaluated consecutive patients with muscle-invasive bladder cancer (MIBC; clinical T2-4aN0M0) treated with RC at our institution from March 2003 to March 2017. We enrolled 20 and 81 patients with UC with SD (UCSD) and pure UC, respectively. Postoperative survival outcomes were compared between the patients with UCSD and pure UC using the Kaplan-Meier method. Pre- and postcystectomy factors that influenced the overall survival (OS) and recurrence-free survival (RFS) were investigated in these patients. Multivariate Cox regression models were used to identify the predictors of OS and RFS. With a median follow-up time of 31 months, the 5-year OS rate of the UCSD and pure UC groups was 41.1% and 69.7% (P = .002) and the 5-year RFS rate was 51.8% and 59.5% (P = .027), respectively. The shape of the Kaplan-Meier curves for UCSD suggested a more rapid course of the disease within the first 2 years than observed in pure UC. Multivariate analyses suggested that SD in UC was significantly associated with OS (hazard ratio [HR]: 4.22; 95% confidence interval [CI]: 1.20-14.8; P = .024) and close to significance for a lower RFS (HR: 2.13, 95% CI: 0.74-6.15, P = .064). Our results indicate that SD may be an independent predictor of OS and RFS in UC of MIBC in patients undergoing RC.

Histologic variants associated with biological aggressiveness and poor prognosis in patients treated with radical cystectomy

BACKGROUND

The prognostic value of histologic variants (HV) after radical cystectomy (RC) remains controversial. We evaluated the clinicopathological features and prognosis in patients with pure urothelial carcinoma (UC) and HV following RC.

METHODS

From 1990 to 2015, 286 patients with bladder cancer were treated with RC at six Kitasato University-affiliated hospitals. All patients were divided into two groups: pure UC and HV, which contained pure variants and mixed-type UC with variant pattern. A comparison of patient characteristics between the two groups was made to assess the clinicopathological features, and statistical analyses were performed to investigate prognosis in the two groups.

RESULTS

Of the 286 patients, 226 (79%) had pure UC, while 60 (21%) had HV. Of all HV, pure variants accounted for 45% (n = 27). The prevalence of lymph node involvement, locally advanced stage (≥ pT3), positive soft tissue surgical margin and lymphovascular invasion were significantly higher in patients with HV than in those with pure UC. Patients with HV showed worse disease-free survival and cancer-specific survival than those with pure UC (P = 0.009 and 0.003, respectively). In multivariate analysis, HV and lymph node involvement were independent predictors of worse disease-free survival (P = 0.017 and 0.001, respectively). HV, locally advanced stage, lymph node involvement, and positive soft tissue surgical margin were also confirmed as independent predictors of worse cancer-specific survival (P = 0.011, 0.012, 0.003 and 0.010, respectively.).

CONCLUSIONS

HV was associated with greater biological aggressiveness and worse prognosis than pure UC.

Glandular differentiation in pT1 urothelial carcinoma of bladder predicts poor prognosis

To evaluate the effect of glandular differentiation (GD) on tumor recurrence and progression of pT1 bladder urothelial carcinoma (UC). We performed a retrospective analysis of 82 bladder urothelial carcinoma with glandular differentiation (UCGD) patients which was pathologically diagnosed as pT1, 166 patients of pT1 UC of bladder without histologic variants served as controls. Patients of UCGD were more likely to have higher recurrence (P = 0.002) rate and higher progression rate (P < 0.001). Moreover, UCGD and a poor 5 -year overall survival (OS) (P = 0.02) while there was no difference in cancer-specific survival (CSS) (P = 0.062) between two groups. According to univariate analysis, largest tumor size (HR 1.502, CI 1.158–1.861, P = 0.029), UCGD (HR 1.787, CI 1.298–2.552, P = 0.001), lymphovascular invasion (LVI) (HR 1.226, CI 1.013–1.945, P = 0.039). UCGD (HR 1.367, CI 1.115–1.853, P = 0.038) and LVI (HR 1.416, CI 1.120–2.254, P = 0.013) were prognostic factors associated with disease recurrence and progression, respectively. Additionally, Additionally, UCGD significantly influence disease recurrence (HR 1.871, CI 1.338–2.589, P < 0.001) and progression (HR 1.462, CI 1.138–2.393, p = 0.007). Similarly, LVI significantly influence disease recurrence (HR 1.356, CI 1.053–2.174, P = 0.042) and progression (HR 1.348, CI 1.052–1.944, p = 0.022) in multivariate analysis. UCGD is significantly associated with higher recurrence and progression rate in patients with newly diagnosed pT1. Recurrent cases should be performed radical cystectomy (RC) earlier.