Small Cell Carcinoma of the Urinary Bladder: A Retrospective, Multicenter Rare Cancer Network Study of 107 Patients

A Single Institution Experience in the Management of Localized Neuroendocrine Carcinoma of the Bladder

BACKGROUND

Neuroendocrine carcinoma of the bladder (NEC-bladder) is a rare disease with poor outcomes and variable treatment approaches.

MATERIALS AND METHODS

Patients with localized NEC-bladder treated with surgery or radiation between 2001-2021 were retrospectively identified. Rates of pathologic complete response (pCR) and downstaging were evaluated following NAC in surgically-treated patients. Progression-free survival (PFS) and overall survival (OS) were analyzed with univariable (log-rank) and multivariable (MVA; Cox regression) methods.

RESULTS

Sixty-five patients were identified having a median age of 73. The tumor histology distribution was small cell (64.6%) or urothelial with NE differentiation (35.4%). Most patients (69.2%) received NAC. Patients received local therapy by surgery (78.5%) or chemoradiation (21.5%). The majority (62.7%) of surgical patients had ≥ pT2 with 37.3% having nodal involvement (pN+). The pCR and downstaging rates were 21.6% and 35.1%, respectively. At a median follow-up of 60 months (m), the median PFS and OS were 16.4m and 25.9m, respectively. NAC improved PFS (p=0.04) and downstaging improved PFS (p=0.012) and OS (p<0.001). Patients receiving NAC with ypN0 vs. ypN+ had median OS of 69.9m vs 15.3m, respectively (p<0.001). MVA identified receipt of NAC and pN as predictors of PFS; pN was predictive of OS. No differences in PFS or OS were seen between histology of primary tumor. The brain metastasis rate was 10.8% with all patients having small cell histology.

CONCLUSIONS

Optimized therapy in NEC-bladder includes NAC followed by local consolidation. Ascertainment of ypN0 is associated with long term survival, while pN+ remains associated with poor outcomes.

Current Advances in the Management of Nonurothelial Subtypes of Bladder Cancer

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

Long-Term Survival After Definitive Concurrent Chemoradiation Therapy for Synchronous Small Cell Neuroendocrine Carcinoma of the Urinary Bladder and Adenocarcinoma of the Prostate: A Case Report

Available reports of synchronous prostate and bladder cancer have exclusively described radical cystoprostatectomy with or without perioperative chemotherapy as the treatment of choice. There are no reports of curative intent or definitive chemoradiation therapy for synchronous primary bladder and primary prostate cancers. Small cell carcinoma of the bladder is a rare and aggressive tumor. We present the first case of synchronous mixed small cell carcinoma and urothelial carcinoma of the urinary bladder and adenocarcinoma of the prostate in a 70-year-old male who attained long-term survival after curative intent and definitive concurrent chemoradiotherapy with minimal acute and late toxicities. The patient remained alive and disease-free at 41 months post-treatment and achieved excellent functional outcomes with organ preservation. Definitive chemoradiation therapy offers a safe and effective, curative-intent organ preservation treatment for localized synchronous prostate and bladder cancers.

Surveillance of prognostic risk factors in patients with SCCB using artificial intelligence: a retrospective study

Small cell carcinoma of the bladder (SCCB) is a rare urological tumor. The prognosis of SCCB is abysmal. Therefore, this study aimed to construct nomograms that predict overall survival (OS) and cancer-specific survival (CSS) in SCCB patients. Information on patients diagnosed with SCCB during 2004-2018 was obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression models analyzed Independent risk factors affecting patients' OS and CSS. Nomograms predicting the OS and CSS were constructed based on the multivariate Cox regression model results. The calibration curve verified the accuracy and reliability of the nomograms, the concordance index (C-index), and the area under the curve (AUC). Decision curve analysis (DCA) assessed the potential clinical value. 975 patients were included in the training set (N = 687) and the validation set (N = 288). Multivariate COX regression models showed that age, marital status, AJCC stage, T stage, M stage, surgical approach, chemotherapy, tumor size, and lung metastasis were independent risk factors affecting the patients' OS. However, distant lymph node metastasis instead AJCC stage is the independent risk factor affecting the CSS in the patients. We successfully constructed nomograms that predict the OS and CSS for SCCB patients. The C index of the training set and the validation set of the OS were 0.747 (95% CI 0.725-0.769) and 0.765 (95% CI 0.736-0.794), respectively. The C index of the CSS were 0.749 (95% CI 0.710-0.773) and 0.786 (95% CI 0.755-0.817), respectively, indicating that the predictive models of the nomograms have excellent discriminative power. The calibration curve and the AUC also show good accuracy and discrimination of the nomograms. To sum up, We established nomograms to predict the OS and CSS of SCCB patients. The nomograms have undergone internal cross-validation and show good accuracy and reliability. The DCA shows that the nomograms have an excellent clinical value that can help doctors make clinical-assisted decision-making.

Comparison of clinicopathological characteristics, gene expression profiles, mutational analysis, and clinical outcomes of pure and mixed small-cell carcinoma of the bladder

AIMS

Small cell bladder carcinoma (SCBC) is a rare, divergent form of urothelial carcinoma (UC). We aimed to determine whether pure (n = 16) and mixed (SCBC and UC; n = 30) tumours differed in pathology, gene expression characteristics, genetic alterations, and clinical outcomes.

METHODS AND RESULTS

Forty (87%) patients received first-line chemotherapy. Twenty-nine patients had no metastatic disease at diagnosis and underwent radical cystectomy. There were no differences in age, sex, race distribution, tumour size, stage at presentation, therapy response with pathological downstaging to ≤ypT1N0, or overall or progression-free survival (PFS) between pure and mixed tumours. There was a longer PFS among downstaged chemotherapy-responding tumours ≤ypT2N0M0 than among unresponsive tumours ≥ypT2 ≥ yN1M1 (P = 0.001). Patients who achieved pathological downstaging with neoadjuvant chemotherapy (n = 10) were stage cT2N0M0 at the time of diagnosis and were alive at the last follow-up (median 37 months), while 46% of patients who failed to achieve pathological downstaging were alive at the last follow-up (median 38 months; P = 0.008). RNA sequencing showed that the UC of mixed SCBC had similar neural expression signatures to pure SCBC. DNA sequencing revealed alterations in TERT (83%), P53 (56%), ARID1A (28%), RB1 (22%), and BRCA2 (11%). Immunohistochemistry for RB1 showed loss of expression in 18/19 (95%) patients, suggesting frequent pathway downregulation despite a low prevalence of RB1 mutation.

CONCLUSION

Patients with pure and mixed SCBC have similar outcomes and these outcomes are determined by the pathological stage at RC and are best among patients who have pathological downstaging after NAC.

Clinical characteristics and treatment outcomes of patients with small cell carcinoma of the urinary bladder

Background

Materials and methods

Results

Conclusions

Small cell carcinoma of the bladder with coexisting prostate adenocarcinoma: two cases report and literature review

BACKGROUND

Primary small cell carcinoma of the bladder (SCCB) is a rare disease of the genitourinary tract and reported limitedly. SCCB is very aggressive and always mixed with other histologic components, but coexistence of SCCB and prostate adenocarcinoma is extremely rare.

CASES PRESENTATION

Two aged males (72 and 58 years) were included in this study. Both of them presented with gross hematuria as initial symptom. Magnetic resonance imaging (MRI) demonstrated protruding lesions in the urinary bladder. Pathological examination after radical cystectomy and prostatectomy showed the concurrence of SCCB and prostate adenocarcinoma. One patient died of liver and lung metastasis 8 months after surgery, and the other patient was still alive after 19 months of follow-up.

CONCLUSION

In this paper, we reported two unusual cases of coexistence of SCCB and prostate adenocarcinoma, and reviewed relative literatures with respect to the epidemiology, clinical features, pathologic features, diagnosis, treatment and prognosis of SCCB.

An ensemble approach of urine sediment image analysis and NMP22 test for detection of bladder cancer cells

Background

Bladder cancer is the eighth most common cancer and the second most common urological cancer in Korean males. Current diagnostic tools for bladder cancer include cystoscopy (an upper tract study), urine cytology, and nuclear matrix protein 22 (NMP22) test. In this study, we evaluated the detection rate of atypical/malignant urothelial cells in urinary sediment images when flagged for positive NMP22 test.

Methods

NMP22 was measured by NMP22 BladderChek Test (Abbott Laboratories) and urine chemical and sediment analysis were performed by fully automated cobas 6500 urine analyzer (Roche Diagnostics). Specimens that met the manual microscopic examination (MME) criteria were then subjected to an on‐screen review of images. We subsequently reviewed sediment images and examined under the microscopy for the flagged cases.

Results

Of the 1217 patients, 345 (28.3%) had positive NMP22 results, whereas 872 (71.7%) had negative results. Out of the positive results, 154 (12.7%) were positive and 191 (15.7%) weakly positive for NMP22. Screened review of flagged specimens (ie, positive NMP22 result) with sediment imaging analysis revealed that suspicious urothelial carcinoma cells were detected in only two cases (0.8%). In the NMP22 negative flagged cases, the suspicious neoplastic cells were not found.

Conclusions

Our findings suggest that the NMP22 test should be added to the flagging criteria for MME to improve diagnostic accuracy. The combination of urine sediment imaging analysis and NMP22 test can significantly assist technicians in the review of specimens.

Clinical Guidance for the Management of Patients with Urothelial Cancers During the COVID-19 Pandemic - Rapid Review

The current COVID-19 pandemic presents a substantial obstacle to cancer patient care. Data from China as well as risk models suppose that cancer patients, particularly those on active, immunosuppressive therapies are at higher risks of severe infection from the illness. In addition, staff illness and restructuring of services to deal with the crisis will inevitably place treatment capacities under significant strain. These guidelines aim to expand on those provided by NHS England regarding cancer care during the coronavirus pandemic by examining the known literature and provide guidance in managing patients with urothelial and rarer urinary tract cancers. In particular, they address the estimated risk and benefits of standard treatments and consider the alternatives in the current situation. As a result, it is recommended that this guidance will help form a framework for shared decision making with patients. Moreover, they do not advise a one-size-fits-all approach but recommend continual assessment of the situation with discussion within and between centres.

Perioperative Chemotherapy in Poorly Differentiated Neuroendocrine Neoplasia of the Bladder: A Multicenter Analysis

There is scant evidence about optimal management of poorly differentiated neuroendocrine carcinoma of the bladder (BNEC). We performed a multicenter retrospective study on BNEC patients from 13 Italian neuroendocrine-dedicated centers to analyze strategies associated with better outcomes. Mixed adeno-neuroendocrine carcinomas (MANEC) were included. We analyzed overall survival (OS) in the overall cohort, relapse-free survival (RFS) in radically operated patients and progression-free survival (PFS) in patients who received chemotherapy for metastatic disease. Fifty-one BNEC patients were included (male: 46, median age: 70 years). Overall, median OS was 16.0 months, radical tumor resection was performed in 37 patients (72.5%) and 11 of these (29.7%) also received peri-operative platinum-etoposide chemotherapy. Median OS was longer in patients with better performance status (PS) and in those with stage I–III disease at diagnosis compared to stage IV. Among patients who underwent radical tumor resection (N = 37), RFS was longer in patients with better PS and showed a trend towards a longer RFS in those treated with peri-operative chemotherapy than with surgery alone (11 vs. 6 months; p = 0.078). Among 28 patients receiving chemotherapy for metastatic disease, PFS was 5.0 months and there was a trend towards improved PFS in patients receiving carboplatin-etoposide chemotherapy compared to other regimens. A multivariate model unmasked a significant association between carboplatin-etoposide chemotherapy and risk for disease progression or death (HR: 0.39 (95%CI: 0.16–0.96) p = 0.040). Performance status might be associated with improved RFS in radically operated patients, while type of chemotherapy might affect PFS in patients receiving chemotherapy for metastatic BNEC.

Limited Stage Small Cell Bladder Cancer: Outcomes of a Contemporary Cohort

BACKGROUND: Limited stage small cell bladder cancer is curable with multi-modality therapy using external beam radiotherapy or radical cystectomy. The optimal management strategy for this rare disease is still debated, yet few case series have described patients treated after 2010. OBJECTIVE: To analyze outcomes from a contemporary cohort of patients undergoing definitive treatment. METHODS: Patients diagnosed with small cell bladder cancer after January 1, 2010 were identified from an institutional database. Clinical histories were collected by chart review. Survival outcomes were analyzed in patients who received curative-intent therapy consisting of bladder radiotherapy or cystectomy. RESULTS: Thirty patients with limited stage disease that received definitive therapy were identified. Seventeen patients received primary radiotherapy, and thirteen underwent cystectomy. Median age was 70 years. Median follow up was 39.6 months (range 7.2–95.8). The median overall survival of patients undergoing radiotherapy or cystectomy were 36.8 and 30.6 months, respectively (hazard ratio 0.99, 95% confidence interval 0.35–2.85). The median metastasis free survival for patients receiving radiotherapy was not reached, and 18.9 months in the cystectomy group (hazard ratio 0.94, 95% confidence interval 0.34–2.61). The most common sites of relapse were lymph node (n = 6) and bone (n = 5). Brain metastases were less common (n = 3). CONCLUSIONS: Patients receiving cystectomy or radiotherapy had similar outcomes in this contemporary series, but definitive comparisons are limited by the cohort size and high censoring rate (53%). Survival in our cohort is improved compared with older reports, though outcomes remain poor, reiterating the need for better therapeutic options.

Survival of Contemporary Patients With Non-metastatic Small-cell Carcinoma of Urinary Bladder, According to Alternative Treatment Modalities

BACKGROUND

The objective of this study was to test the effect of chemotherapy and/or radical cystectomy (RC) and/or radiotherapy (RT) on survival of patients with non-metastatic small-cell carcinoma of the urinary bladder (SCCUB).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results registry (2001-2016), we identified patients with non-metastatic (T1-4, N0, M0) SCCUB. Treatment was defined as: chemotherapy alone, chemotherapy + RC, and chemotherapy + RT. Temporal trends, cumulative incidence plots, and multivariable competing risks regression models were used.

RESULTS

Of 595 patients with SCCUB, 230 (38.5%), 159 (27%), and 206 (34.5%) were treated with chemotherapy alone, chemotherapy + RC, and chemotherapy + RT, respectively. The rates of chemotherapy + RC increased (estimated annual percentage changes [EAPC], +5.9%; P = .002). Conversely, chemotherapy alone (EAPC, -1.7%; P = .1) and chemotherapy + RT rates decreased (EAPC: -2.2%; P = .08). Overall, 5-year cancer-specific mortality (CSM) rates were 44%, 29%, and 40% for patients treated with chemotherapy alone, chemotherapy + RC, and chemotherapy + RT, respectively (P = .004). Relative to chemotherapy alone, patients treated with chemotherapy + RC experienced lower CSM (hazard ratio, 0.5; P < .001). Conversely, patients treated with chemotherapy + RT did not exhibit any CSM benefit (hazard ratio, 0.8; P = .2), when compared with chemotherapy alone.

CONCLUSION

In contemporary patients with SCCUB with non-metastatic disease, the rates of chemotherapy + RC are increasing. Conversely, the rates of combined chemotherapy with RT and chemotherapy alone are decreasing. These patterns of treatment are in agreement with better cancer control in patients with SCCUB. In consequence, until more robust data become available, the combination of chemotherapy and RC should represent the recommended treatment strategy.

Validation of a neuroendocrine-like classifier confirms poor outcomes in patients with bladder cancer treated with cisplatin-based neoadjuvant chemotherapy

PURPOSE

Neuroendocrine (NE)-like carcinoma is a newly recognized molecular subtype of conventional urothelial carcinoma of the bladder with transcriptomic profiles and clinical outcomes highly similar to histological NE carcinoma. The identification of NE-like tumors is challenging, as these tumors often appear histologically like urothelial carcinoma and can be missed by routine morphological criteria. We previously developed a single-sample classifier to identify NE-like tumors, which we aimed to validate in an independent cohort.

MATERIALS AND METHODS

A single-sample genomic classifier was performed on transurethral specimens from a retrospective multicenter cohort of 234 patients who underwent cisplatin-based neoadjuvant chemotherapy and subsequent radical cystectomy. Outcomes were compared for NE-like vs. non-NE-like.

RESULTS

We identified 10 patients with urothelial tumors of the NE-like subtype, all of which had robust gene expression of neuronal markers, but did not express markers associated with basal or luminal tumors. The cancer-specific mortality rates were significantly higher compared to non-NE-like tumors (P < 0.001), with 5 of the 10 patients dying within 12 months from surgery.

CONCLUSIONS

The single-sample classifier was able to identify urothelial carcinomas with NE-like subtype. These NE-like tumors have demonstrated transcriptomic profiles and clinical behavior similar to histological NE tumors across multiple patient cohorts. We propose that NE-like tumors should be managed similarly to histological NE tumors, and that standard treatments for small cell lung cancer as well as novel strategies may be evaluated in these patients.

Small cell carcinoma of the bladder: the characteristics of molecular alterations, treatment, and follow-up

Small cell carcinoma of the bladder (SCCB) is a rare disease associated with high invasiveness and mortality. Histologically, SCCB is difficult to distinguish from small cell lung cancer (SCLC); however, it shares more similar molecular alterations with urothelial carcinoma (UC). As a result, now, the widely accepted theory about the cells of origin is that SCCB and UC probably have a common clone origin. Even the former probably comes from a preexisting UC. At present, given its rarity, early diagnoses, treatments, and follow-ups are not well established, which are vital to patients with SCCB. Inspirationally, in recent years, with the development of molecular diagnostic methods, molecular alterations of SCCB have been understood partially, which are propitious to excavate new potential therapeutic strategies and establish sound follow-ups. Therefore, the future will be light for patients with SCCB.

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.

Clinical outcomes of patients with pure small cell carcinoma of the urinary bladder

OBJECTIVES

There is not yet a standardized approach to treat patients with small cell carcinoma of the bladder (SmCCB). This study aims to investigate the clinical features, treatment, and survival outcomes of patients with pure SmCCB.

MATERIALS AND METHODS

Patients diagnosed with SmCCB between January 2006 and September 2015 were retrospectively evaluated.

RESULTS

A total of 34 patients with a median age of 63.0 years were included in the study, with a male to female ratio of 4.6:1.0. At the time of diagnosis, 22 patients (64.7%) had stage IV disease. At a median follow-up time of 12.7 months, 67.6% of patients died of bladder carcinoma, with an overall survival (OS) of 15.7 months for all patients. In the patients with stages I-III, nodal involvement, and distant metastases, the median OS was 31.8, 15.7, and 8.4 months, respectively (P = 0.005). Considering the survival rates of the patients (stages I-III) treated with surgery vs. local therapy, there was not a statistically significant difference (26.6 months and 31.8 months, P = 0.97, respectively). A multivariate analysis revealed that stage IV disease and poor ECOG performance status were associated with OS.

CONCLUSION

The optimal treatment of SmCCB has been under debate. For the patients with advanced stage of disease (T4b, N+, M+), platinum containing chemotherapeutic agents should be preferred. Stage IV disease and poor ECOG performance status were associated with shorter OS.

Organ-preserving approach via radiotherapy for small cell carcinoma of the bladder: an analysis based on the Japanese Radiation Oncology Study Group (JROSG) survey

Small cell carcinoma of the bladder is extremely rare, accounting for <1% of all malignant tumours in the urinary tract. Thus, no standard therapy modality for this malignancy has been established. This study aimed to retrospectively analyse the clinical outcomes associated with definitive radiotherapy for small cell carcinoma of the bladder. A questionnaire-based survey of patients with pathologically proven small cell carcinoma of the bladder treated with definitive radiation therapy between 1990 and 2010 was conducted by the Japanese Radiation Oncology Study Group. The clinical records of 12 eligible patients were collected from nine institutions. The median age of the patients was 70.5 years (range: 44-87 years), and the median follow-up period was 27.3 months (range: 3.3-117.8 months). The median prescribed dose was 60 Gy (range: 50.0-61.0 Gy), and a median of 2.0 Gy (range: 1.2-2.0 Gy) was administered per fraction. Systemic chemotherapy combined with radiotherapy was performed in eight cases (66.7%). The 3- and 5-year overall survival rates were 50.0% and 33.3%, respectively. And the 3- and 5-year local control rates were 66.7% and 55.6%, respectively. Chemotherapy significantly improved overall survival and relapse-free survival (P = 0.006 and 0.001, respectively). No serious adverse events occurred in the observation period. All patients who achieved local control maintained functional bladders. In conclusion, radiotherapy is a potential local treatment option and has an important role in maintaining quality of life. Systemic chemotherapy combined with local radiotherapy seems to be effective in improving survival.

The oncological outcomes of small cell carcinoma of the bladder

INTRODUCTION

Small cell carcinoma of the bladder (SmCC) is a rare and aggressive genitourinary malignancy. The paucity of clinical trials and outcome data provide no standard treatment guidelines. Accordingly, patient prognosis is poor. Our goal was to present the first comprehensive in-depth analysis of SmCC in a tertiary Canadian centre.

METHODS

We retrospectively reviewed all patients diagnosed with primary SmCC at the London Regional Cancer Program between January 1990 and 2016. The primary outcome was overall survival (OS). We examined a number of secondary outcomes and baseline characteristics.

RESULTS

We identified 15 men and six women (median age 72 years) with a SmCC diagnosis (median followup 11.33 months). Median Charlson Comorbidity Index score was 7 (interquartile range [IQR] 5-10) and 15 patients had a smoking history. Most common presentation was gross hematuria (18 patients, 86%), and pT2 stage at transurethral resection of the bladder tumour (TURBT) (n= 7/21, 33%), although five patients had cT4 (24%). Pure SmCC was found in nine individuals (43%), whereas 12 had mixed differentiation (57%). From initial staging, 15 patients had extravesical disease (71%), 10 had positive pelvic lymphadenopathy (48%), and distant metastases occurred in six (29%). In our series, five individuals (24%) underwent cystectomy, 18 (86%) received radiation, and 14 (67%) received adjuvant chemotherapy. The median OS was 15 months (two-year OS was 19%).

CONCLUSIONS

SmCC is a rare and aggressive form of bladder cancer. Despite multimodal therapy, prognosis remains guarded, with little improvement seen over the study's 25-year duration. An understanding of study limitations is warranted in interpretation of results.

Transcriptomic and Protein Analysis of Small-cell Bladder Cancer (SCBC) Identifies Prognostic Biomarkers and DLL3 as a Relevant Therapeutic Target

PURPOSE

Transcriptomic profiling can shed light on the biology of small-cell bladder cancer (SCBC), nominating biomarkers, and novel therapeutic targets.

EXPERIMENTAL DESIGN

Sixty-three patients with SCBC had small-cell histology confirmed and quantified by a genitourinary pathologist. Gene expression profiling was performed for 39 primary tumor samples, 1 metastatic sample, and 6 adjacent normal urothelium samples (46 total) from the same cohort. Protein levels of differentially expressed therapeutic targets, DLL3 and PDL1, and also CD56 and ASCL1, were confirmed by IHC. A SCBC PDX model was utilized to assess in vivo efficacy of DLL3-targeting antibody-drug conjugate (ADC).

RESULTS

Unsupervised hierarchical clustering of 46 samples produced 4 clusters that correlated with clinical phenotypes. Patients whose tumors had the most "normal-like" pattern of gene expression had longer overall survival (OS) compared with the other 3 clusters while patients with the most "metastasis-like" pattern had the shortest OS (P = 0.047). Expression of DLL3, PDL1, ASCL1, and CD56 was confirmed by IHC in 68%, 30%, 52%, and 81% of tissue samples, respectively. In a multivariate analysis, DLL3 protein expression on >10% and CD56 expression on >30% of tumor cells were both prognostic of shorter OS (P = 0.03 each). A DLL3-targeting ADC showed durable antitumor efficacy in a SCBC PDX model.

CONCLUSIONS

Gene expression patterns in SCBC are associated with distinct clinical phenotypes ranging from more indolent to aggressive disease. Overexpression of DLL3 mRNA and protein is common in SCBC and correlates with shorter OS. A DLL3-targeted ADC demonstrated in vivo efficacy superior to chemotherapy in a PDX model of SCBC.

Clinicopathological characteristics and survival outcomes of bladder neuroendocrine carcinomas: a population-based study

Background

Bladder neuroendocrine carcinomas (BNECs) are relatively a rare type of tumor. The aim of this study was to examine the clinicopathological characteristics and predictors of survival outcomes of patients with BNECs based on the analysis of the national Surveillance, Epidemiology, and End Results (SEER) database.

Materials and methods

Kaplan-Meier analysis with log-rank test was used for survival comparisons. Multivariate Cox regression model was employed to analyze the effect of different treatments on overall survival (OS) and cancer-specific survival (CSS).

Results

A total of 910 patients were identified between 2004 and 2014. Overall, 648 (71.2%) patients had small cell neuroendocrine carcinoma (SCNEC), 35 (3.8%) had large cell neuroendocrine carcinoma (LCNEC), 10 (1.1%) had carcinoid tumor (well-differentiated neuroendocrine tumor), 16 (1.8%) had paraganglioma/pheochromocytoma (PGL/PHEO), 619 (68.0%) had a poorly differentiated or undifferentiated histology grade, 214 (23.5%) presented with metastatic disease, 586 (64.4%) underwent transurethral ablation/destruction for bladder tumor, and 245 (26.9%) had partial/total cystectomy. Cystectomy+chemotherapy+radiotherapy (CCR) has the highest long-term survival rate among various treatments. The 1-, 3-, and 5-years CSS of CCR were 56%, 56%, and 56%, respectively. By using multivariable Cox proportional hazard model, age, histology, N stage, SEER stage, tumor size, radiotherapy, chemotherapy, and local treatment of the primary site were identified as independent predictors for OS and CSS; all P<0.05.

Conclusion

In BNEC, SCNEC has an absolute advantage in number. SCNEC/LCNEC tend to be older men. PGL/PHEO and carcinoid tumors have younger mean ages, earlier tumor stages, and better prognosis than SCNEC/LCNEC. Surgery, radiotherapy and chemotherapy are better than conservative treatment. However, whatever cystectomy or bladder sparing, chemotherapy should be a major component of treatment.

[Small cell neuroendocrine carcinoma of the bladder: Report of five cases and a review of the literature]

Neuroendocrine small cell carcinoma of the bladder is a rare and aggressive tumour, accounting for less than 1% of all bladder tumours. Given its rarity and the absence of randomized trials, the therapeutic management of these tumours remains difficult. By analogy with small cell lung cancer, multimodal treatment is often proposed. Radical cystectomy plus chemotherapy and chemoradiation therapy are associated with better survival compared to monotherapy. We report our experience in the management of these tumours with literature review.

Small Cell Carcinoma of Urinary Bladder: Analysis from a Tertiary Cancer Care Center of India

Context: Small cell cancer of the urinary bladder. Aims: Small cell carcinoma of the bladder is a rare histological subtype, which is particularly aggressive and global literature available describing this entity is sparse. This review of our database was to evaluate clinicopathological and survival outcomes of these patients. Subjects and Methods: The present study was a retrospective analysis of patients with small cell bladder cancer for past 6 years at Rajiv Gandhi Cancer Institute and Research Center, New Delhi. Results:: Most of the patients in our study presented with limited stage disease. The overall survival and disease-free survival (DFS) was 49% and 51.07% at 2 years, respectively. Preoperative chemotherapy with surgical resection has shown significant survival and DFS benefit. Stage at presentation also affected the survival and DFS though it did not reach statistical significance. Conclusions: Small cell bladder cancer is a rare disease with dismal prognosis. Multimodality treatment with neoadjuvant chemotherapy should be the preferred treatment for limited stage disease.

Small cell carcinoma of the urinary bladder: a clinicopathological and immunohistochemical analysis of 81 cases

Small cell carcinoma (SmCC) of the bladder is a rare disease. We retrospectively studied a large series of bladder SmCC from a single institution. The patients included 69 men and 12 women with a mean age of 68 years. Most bladder SmCCs were presented at advanced stage, with tumors invading the muscularis propria and beyond (n = 77). SmCC was pure in 27 cases and mixed with other histologic types in 54 cases, including urothelial carcinoma (UC) (n = 32), UC in situ (n = 26), glandular (n = 14), micropapillary (n = 4), sarcomatoid (n = 4), squamous (n = 3), and plasmacytoid (n = 1) features. Most SmCCs expressed neuroendocrine markers synaptophysin (41/56), chromogranin (26/55), and CD56 (39/41); however, they did not express UC luminal markers CK20 (0/17), GATA3 (1/30), and uroplakin II (1/22). Some SmCCs showed focal expression of CK5/6 (9/25), a marker for the basal molecular subtype. Furthermore, expression of the retinoblastoma 1 (RB1) gene protein was lost in most of the bladder SmCCs (2/23). The patients' survival was significantly associated with cancer stage but did not show a significant difference between mixed and pure SmCCs. Compared with conventional UC at similar stages, SmCC had a worse prognosis only when patients developed metastatic diseases. In conclusion, bladder SmCC is an aggressive disease that is frequently present at an advanced stage. A fraction of SmCCs show a basal molecular subtype, which may underlie its good response to chemotherapy. Inactivation of the RB1 gene may be implicated in the oncogenesis of bladder SmCC.

Nomograms to Predict Individual Prognosis of Patients with Primary Small Cell Carcinoma of the Bladder

Objectives: To develop reliable nomograms to estimate individualized overall survival (OS) and cancer specific survival (CSS) for patients with primary small cell carcinoma of the bladder (SCCB) and compare the predictive value with the AJCC stages.

Patients and Methods: 582 eligible SCCB patients identified in the Surveillance, Epidemiology, and End Results (SEER) dataset were randomly divided into training (n=482) and validation (n=100) cohorts. Akaike information criterion was used to select the clinically important variables in multivariate Cox models when establishing nomograms. The performance of nomograms was bootstrapped validated internally and externally using the concordance index (C-index) with 95% confidence interval (95% CI) and calibration curves and was compared with that of the AJCC stages using C-index, Kaplan-Meier curves and decision curve analysis (DCA).

Results: Two nomograms shared common indicators including age, tumor size, T stage, lymph node ratio, metastases, chemotherapy, radiation and radical cystectomy, while marriage and gender were only incorporated in the OS nomogram. The C-indices of nomograms for OS and CSS were 0.736 (95%CI 0.711-0.761) and 0.731(95%CI 0.704-0.758), respectively, indicating considerable predictive accuracy. Calibration curves showed consistency between the nomograms and the actual observation. The results remained reproducible when nomograms were applied to the validation cohort. Additionally, comparisons between C-indices, Kaplan-Meier curves and DCA proved that the nomograms obtained obvious superiority over the AJCC stages with wide practical threshold probabilities.

Conclusions: We proposed the first two nomograms for individualized prediction of OS and CSS in SCCB patients with satisfactory predictive accuracy, good robustness and wide applicability.

The prognostic value of histological subtype in patients with metastatic bladder cancer

We aim to evaluate the prognostic effect of the histological sub-type in patients with metastatic bladder cancer based on the Surveillance Epidemiology and End Results database. A total of 2634 eligible patients were included. The histological subtypes were: transitional cell carcinoma (TCC; 75.2%); adenocarcinoma (3.3%); squamous cell carcinoma (SQCC; 4.1%); and small cell carcinoma (4.3%). A significant association of adenocarcinoma with better survival outcomes (P < 0.015), and that of SQCC with worse outcomes (P < 0.001) was observed. On multivariate analysis, adenocarcinoma was significantly associated with longer and SQCC with shorter survival time as compared to TCC. Overall, 1331 (50.5%) patients had a single metastatic site and 523 (19.9%) had multiple sites involved. Single-site metastasis had a better survival outcome than multiple metastases (P < 0.001). Histological sub-type and presence of multiple metastatic sites are independent predictors of survival time. Prospective, in-depth research is needed to determine optimal therapeutic strategies for different histological subtypes of bladder cancer with different metastatic patterns.

Differential expression profile analysis of lncRNA UCA1α regulated mRNAs in bladder cancer

Urothelial carcinoma associated 1α (UCA1α) is a novel long non-coding RNA (lncRNA) that regulates bladder cancer proliferation, migration, and invasion. The target genes of UCA1α have, however, not been identified. To address this, a pCDNA3.1(+)-UCA1α over-expression vector was transfected into UM-UC-2 bladder cancer cells. Genes differentially expressed between pCDNA3.1(+)-UCA1α and pCDNA3.1(+) transfected cell were then detected by microarray and bioinformatics analysis. A total of 71 differentially expressed genes were identified, including 52 up-regulated genes and 19 down-regulated genes. As expected, the lncRNA UCA1α expression level was significantly increased when compared to that of pCDNA3.1(+) transfected cells. The five most significantly up-regulated and five most significantly down-regulated genes were selected, and their expression levels were also assessed by real time quantitative polymerase chain reaction and Western blot. The mRNA and protein expression levels of FOXI3 and GSTA3 were found to be significantly increased, and those of MED18 and TEX101 were found to be significantly decreased. Gene ontology (GO) clustering identified several significant biological processes, cellular components, and molecular functions, associated with lncRNA UCA1α over-expression. The differentially expressed genes were involved in several significant pathways as shown by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway clustering. Cell proliferation activity was significantly increased following overexpression of lncRNA UCA1α increasing over culture time. The present study identifies, for the first time, potential target genes for lncRNA UCA1α in bladder cancer, and provides a significant reference for studying the role of lncRNA UCA1α in bladder cancer.

[PRIMARY SMALL CELL NEUROENDOCRINE CARCINOMA OF THE URETER]

Primary small cell neuroendocrine carcinoma of the upper urinary tract is a rare disease that is associated with a poor prognosis. An 81-year-old man was diagnosed with carcinoma of the stomach and underwent laparoscopic distal gastrectomy. Computed tomography (CT) revealed carcinoma of the left ureter and left hydronephrosis. The patient was diagnosed with carcinoma of the left ureter (cT2N0M0) and left laparoscopic radical nephroureterectomy was performed via a retroperitoneal approach. The pathological diagnosis was left ureter carcinoma (small cell neuroendocrine carcinoma, pT3). He was treated with four courses of the CE regimen (carboplatin area under the curve: 5, intravenously [IV] on day 1 and etoposide [80 mg/m²], IV on days 1-3). There is no evidence of disease at 21 months after radical nephroureterectomy.

Clinicopathologic characteristics, therapy and outcomes of patients with primary ureteral small cell carcinoma: a case series and systematic review of the literature

Purpose

The aim of this case series was to review the standard diagnosis and treatment procedures of primary small cell carcinoma (SCC) in our institution and discuss the clinicopathologic characteristics, treatments and outcomes of patients with primary ureteral SCC.

Patients and methods

Patients diagnosed with ureteral SCC in Peking University First Hospital, Beijing, China, from January 2007 to December 2016 were included. In addition, we performed a systematic literature review, in October 2016, on case reports and case series of ureteral SCC. The clinicopathologic characteristics, treatments and outcomes of this rare disease were analyzed.

Results

A total of 32 patients were included in our analysis (4 cases from our institution and 28 cases from the literature). Most patients (71.0%) were male with an average age of 66.6 years (range 48–80 years). The most common symptoms were hematuria (n=14, 48.3%) and flank pain (n=14, 48.3%). All patients underwent surgery, with 12 (37.5%) patients undergoing multimodality therapy. Regional or distant recurrences developed in 11 patients, among which only 1 patient had bladder recurrence. The overall median survival of the patients was 17 months, with 1- and 3-year survival rates of 51.9% and 30.3%, respectively. In a univariate analysis, female (P=0.009), pure SCC (P=0.03) and advanced T stage (P=0.04) were associated with worse overall survival.

Conclusion

Ureteral SCCs are extremely rare neoplasms with aggressive natural history and poor prognosis. T stage, tumor components and gender may be important factors influencing prognosis. A multimodality treatment is recommended for management. However, further studies are needed to improve the treatment strategy.

Utility of Clinical Risk Stratification in the Selection of Muscle-Invasive Bladder Cancer Patients for Neoadjuvant Chemotherapy: A Retrospective Cohort Study

Introduction: Level I evidence supports the use of cisplatin-based neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer prior to radical cystectomy (RC). On average, 30–40% of patients achieve a complete pathologic response (i.e., stage pT0) after receiving NAC. Some centers risk-stratify patients, suggesting that there may be a higher-risk population that would derive the most benefit from NAC. Recently, a risk-stratification model developed at M.D. Anderson Cancer Center (MDACC) specified criteria for clinical staging and patient selection for NAC. We applied this model to our own RC patient cohort and evaluated our own experience with clinical risk stratification and the effect of NAC on post treatment risk categories.

Methods: We retrospectively reviewed the charts of consecutive patients who underwent RC at two institutions between 2004 and 2014 and noted whether or not they received NAC. We determined the clinical stage by reviewing the exam under anesthesia, transurethral resection biopsy (TURBT) pathology, and preoperative imaging. Patients with cT2-T4a node-negative disease were included. Those with sarcomatoid features or adenocarcinoma were excluded. Patients were classified as high risk if they had tumor-associated hydronephrosis, clinical stage≥T3b-T4a disease, variant histology (i.e., micropapillary or small cell), or lymphovascular invasion (LVI), as specified by the MDACC model. Variables were examined for associations with cancer-specific survival (CSS), overall survival (OS), and risk-category reclassification.

Results: We identified 166 patients with a median follow-up time of 22.2 months. In all, 117 patients (70.5%) did not receive NAC, 68 (58.1%) of whom we classified as high risk. Among patients not receiving NAC, CSS and OS were significantly decreased in high-risk patients (log-rank test p = 0.01 for both comparisons). The estimated age-adjusted hazard ratios of high-risk classification for cancer-specific and overall death were 3.2 (95% CI: 1.2 to 8.6) and 2.2 (95% CI: 1.1 to 4.4), respectively. On post-RC final pathology, 23 (46.9%) low-risk patients were up-classified to high risk and 17 (25.0%) high-risk patients were down-classified. Complete pathologic responses (pT0) were achieved in 7 (6.0%) patients and partial responses (pT1, pTa, pTis) were achieved in 28 (23.9%) patients. Of the 49 patients who did receive NAC, 43 (87.8%) received cisplatin-based and six (12.2%) received carboplatin-based regimens. Applying the MDACC model, we categorized 41 (83.7%) patients as high risk prior to NAC treatment. On final pathology, 3 (37.5%) low-risk patients were up-classified and 17 (41.5%) high-risk patients were down-classified. Complete pathologic responses (pT0) were seen in 13 (26.5%) patients and partial responses were seen in 10 (20.4%) patients. Although the utilization of NAC was not statistically significantly associated with CSS or OS (log-rank test p > 0.05 for both comparisons), it was associated with a 1.2 times increased odds (95% CI: 0.4 to 2.1) of post-RC reclassification from high to low risk on age-adjusted logistic regression.

Conclusions: We found similar results using the clinical risk-stratification model in our cohort and showed that the high-risk category was associated with lower CSS and OS. NAC was associated with a higher probability of risk reclassification from high to low risk.

Rare Occurrence of a Poorly Differentiated Neuroendocrine Tumor of the Bladder

Neuroendocrine tumors rarely occur in the urinary bladder. They can be carcinomatous, subdivided into small cell and large cell pathology. Small cell carcinoma of the bladder is a rarity that may present at an advanced pathologic stage. No treatment regimens have been standardized for local or metastatic disease. Review of the recent literature shows equivalent survival data for localized disease treated with chemoradiotherapy combined with either bladder sparing surgery or radical cystectomy. Patients with significant comorbidities are an additional challenge. We report a case of poorly differentiated neuroendocrine tumor of the bladder, which could not be classified as small or large cell carcinoma, complicated by significant comorbidities. After management with transurethral resection of the tumor, adjuvant chemotherapy, and radiation, the patient is alive and asymptomatic nearly 1 year after initial TURBT with no evidence of disease recurrence.

Transdifferentiation of Small Cell Carcinoma of the Urinary Bladder from Urothelial Carcinoma after Transurethral Resection of a Bladder Tumor, Intravesical Bacillus Calmette-Guerin Instillation, and Chemotherapy: A Case Report

A 73-year-old male underwent transurethral resection of a bladder tumor in August 2010 and April 2011. Pathological examination revealed urothelial carcinoma. After the surgery, chemotherapy and intravesical Bacillus Calmette-Guerin instillation were performed. In September 2014, he once again underwent transurethral resection of the bladder tumor for recurrence, and was again diagnosed with urothelial carcinoma, pT2, by pathological examination. After neoadjuvant chemotherapy, radical cystectomy for tumor recurrence was performed. Pathological examination at this time revealed small cell carcinoma, pT3N0. It is rare for urothelial carcinoma to change to small cell carcinoma, and the mechanism and cause of this change are still unknown. In this case report, we discuss what causes small cell carcinoma of the urinary bladder and review the literature regarding its origin.

Variant histology in bladder cancer: how it should change the management in non-muscle invasive and muscle invasive disease?

Bladder cancer (BC) is a frequent type of carcinoma with an estimated incidence of approximately 100,000 men and women each year in the European Union (EU) with an associated mortality of 30,000 of these patients. In more than 70% the disease is diagnosed in a non-muscle invasive stage with the chance of minimally invasive, local treatment only, which might be required repetitively due to high rate of recurrence. In contrast, muscle invasive or metastatic stages need multimodal treatment strategies including surgical treatment and chemotherapy (CTX) in neoadjuvant (NAC), adjuvant, or palliative settings. Therapy recommendations and guidelines mainly refer to the most common histological type of BC, pure urothelial carcinoma (UC). However, BC can be classified as urothelial and non-UC. Non-urothelial BC and variants of UC account for up to 25% of all BCs. Further discrimination can be made into epithelial and non-epithelial non-UC. Most of the non-UCs are of epithelial origin (approximately 90%) including squamous-cell carcinoma, adenocarcinoma and small-cell carcinoma. Non-epithelial tumors are rare and include variants as sarcoma, carcinosarcoma, paraganglioma, melanoma and lymphoma. Even though it is unclear whether the prognosis of non-urothelial cancer truly differs from that of UC, there is evidence that additional variant histology might prognosticate an impaired prognosis. Accordingly, aggressive behavior and often advanced stages at primary presentation are frequently observed in non-UC arguing for radical and sometimes different treatment strategies as compared to pure UC. This review aims to summarize the available data for the most common histological variants of non-urothelial BC.

Neuroendocrine Tumors of the Urinary Bladder According to the 2016 World Health Organization Classification: Molecular and Clinical Characteristics

Neuroendocrine neoplasms of the urinary bladder are a rare type of tumor that account for a small percentage of urinary bladder neoplasms. These tumors of the urinary bladder range from well-differentiated neuroendocrine neoplasms (carcinoids) to the more aggressive subtypes such as small cell carcinoma. Despite the rarity of the neuroendocrine tumors of the bladder, there has been substantial investigation into the underlying genomic, molecular, and the cellular alterations within this group of neoplasms. Accordingly, these findings are increasingly incorporated into the understanding of clinical aspects of these neoplasms. In this review, we provide an overview of recent literature related to the 2016 World Health Organization Classification of Neuroendocrine Tumors of the Urinary Bladder. Particular emphasis is placed on molecular alterations and recently described gene expression. The neuroendocrine tumors of the urinary bladder are subdivided into four subtypes. Similar to their pulmonary and other extrapulmonary site counterparts, these have different degrees of neuroendocrine differentiation and morphological features. The clinical aspects of four subtypes of neuroendocrine tumor are discussed with emphasis of the most recent developments in diagnosis, treatment, and prognosis. An understanding of molecular basis of neuroendocrine tumors will provide a base of knowledge for future investigations into this group of unusual bladder neoplasms.

Small cell carcinoma of the urinary bladder: changing trends in the current literature

Background Extrapulmonary small cell carcinoma (SmCC), also known as oat cell carcinoma or small cell neuroendocrine carcinoma, is characterized by an aggressive clinical course with early metastasis pattern and a short life expectancy. So far, there is no prospective, data-based case-control study due to its low incidence. The purpose of this paper is to discuss the epidemiology, morphopathology, clinical characteristics, differential diagnosis and treatment of bladder SmCC in the light of the literature. Scope PubMed and American Society of Clinical Oncology Meeting abstracts were searched according to the following keywords: 'extrapulmonary SmCC', 'bladder cancer', and 'therapeutic approach'. The last search was performed on 1 October 2015. Some additional papers were determined by reviewing references of the appropriate articles. Most of the data regarding small cell carcinoma of the urinary bladder (SmCCB) were found to be based on the retrospective trials. Findings Bladder SmCC is more frequent in men and usually appears in the seventh to eighth decades. Macroscopic hematuria is the most common clinical symptom. The diagnosis of SmCCB is performed based on the same criteria determined by the WHO classification for the diagnosis of small cell lung carcinoma (SCLC). Prognosis is closely correlated with the stage at presentation. Although the prognosis of the disease is poor, a long survival can be achieved particularly by radical surgery following neoadjuvant chemotherapy in patients with early stage tumors. Cystectomy is still the current standard local treatment. However, cystectomy alone is not sufficient. Chemotherapy and definitive radiotherapy should be preferred for limited disease in patients who are not candidate for surgery. Conclusion Considering the poor prognosis of the disease, further studies are needed to determine the optimal treatment options and new molecular markers in the way of early diagnosis and favorable outcomes. Prospective, multicenter, randomized studies are required to evaluate the role of neoadjuvant chemotherapy followed either by surgery or radiotherapy.

The Present and Future Opportunities of the Rare Cancer Network: An International Consortium for Advancement of Oncologic Care

To date, the Rare Cancer Network (RCN) has initiated more than 90 studies and 54 peer-reviewed publications were produced as a result. The Second International Symposium of the Rare Cancer Network recently took place in Istanbul, Turkey on April 17-18, 2015, and update was given on multiple currently ongoing projects, while also giving room for new proposals which will shape the direction of future studies for the group. This companion issue of the RCN Proceedings summarized the findings of this meeting, while also serving as a call for fresh projects and papers which will continue to energize the group and advance the oncologic science. A brief introduction to the principles, history, and vision of the RCN was also included. To review, the academic year of 2014-15 marked an enormous success for the international members of the RCN, with the generation of 8 fully published papers and more than 12 newly proposed topics. By the collective efforts of all RCN members, in the future, we look forward to the upcoming opportunities in continuing to advance the standard of chemo- and radiotherapeutic oncologic care for selected rare tumor topics. The studies of these rare cancers often do not allow the design and execution of prospectively enrolled trials; however, these uncommon malignancies do impact the humankind and add to its suffering globally in significant ways.