Prognostic Variables in Patients With Non-metastatic Small-cell Neuroendocrine Carcinoma of the Bladder: A Population-Based Study

Updates on Urinary Bladder Tumors With Neuroendocrine Features

The most common neuroendocrine tumor in the urinary bladder is small cell carcinoma, which can be pure or mixed with components of urothelial or other histologic subtypes. Large cell neuroendocrine carcinoma of the bladder is rare and remains ill-defined but is increasingly recognized. Well-differentiated neuroendocrine tumor and paraganglioma can arise in the bladder but are very rare in this location. Recent advances in molecular characterization allowed for better classification and may offer improved stratification of these tumors.

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.

Long-term Outcomes of Local and Metastatic Small Cell Carcinoma of the Urinary Bladder and Genomic Analysis of Patients Treated With Neoadjuvant Chemotherapy

INTRODUCTION

Small cell carcinoma of the bladder (SCCB) is a rare variant of bladder cancer with poor outcomes. We evaluated long-term outcomes of nonmetastatic (M0) and metastatic (M1) SCCB and correlated pathologic response with genomic alterations of patients treated with neoadjuvant chemotherapy (NAC).

PATIENTS AND METHODS

Clinical history and pathology samples from SCCB patients diagnosed at our institution were reviewed.

RESULTS

One hundred and ninety-nine SCCB patients were identified. (M0: 147 [74%]; M1: 52 [26%]). Among M0 patients, 108 underwent radical cystectomy (RC) (NAC: 71; RC only: 23; adjuvant chemotherapy: 14); 14 received chemoradiotherapy; the rest received chemotherapy alone or no cancer-directed therapy. RC-only patients had a median follow-up of 9.1 years, and median disease-free survival (DFS) and overall survival (OS) were 1.1 and 1.2 years, respectively. NAC patients had pathologic response (<pT2pN0) and pathologic complete response (pT0pN0) rates of 48% and 38%, respectively, with median follow-up of 7.2 years, and median DFS and OS of 5.6 and 14.5 years, respectively. NAC responders (<ypT2N0) had superior median DFS (14.5 vs. 0.6 years, hazard ratio [HR] 0.24, P< .001) and OS (14.5 vs. 2.5 years, HR 0.31, P = .002). DFS rates for responders and nonresponders were 76% and 27% at 5 years, and 71% and 23% at 10 years, respectively. Local and central nervous system recurrences were infrequent. Median progression-free survival (PFS) and OS for M1 disease were 6.9 and 10.3 months, respectively. Genomic profiling was performed on 47 NAC patients. Loss of ERCC2 function was significantly enriched among those with pathologic complete response to NAC (mutations present in 50% of pathologic complete responders vs. 15% nonresponders, P = .045).

CONCLUSION

M0 SCCB is chemo-sensitive and patients have excellent long-term survival following response to NAC. Patients with M1 disease have poor survival despite systemic therapy. Loss-of-function mutations of ERCC2 were associated with pathologic complete response to NAC.

Prognostic Factors of Survival for High-Grade Neuroendocrine Neoplasia of the Bladder: A SEER Database Analysis

Background: High-grade neuroendocrine carcinoma (NEC) is a rare and aggressive variant of bladder cancer. Considering its rarity, its therapeutic management is challenging and not standardized. Methods: We analyzed data extracted from the Surveillance, Epidemiology, and End Results (SEER) registry to evaluate prognostic factors for high-grade NEC of the bladder. Results: We extracted data on 1134 patients: 77.6% were small cell NEC, 14.6% were NEC, 5.5% were mixed neuro-endocrine non-neuroendocrine neoplasia, and 2.3% were large cell NEC. The stage at diagnosis was localized for 45% of patients, lymph nodal disease (N+M0) for 9.2% of patients, and metastatic disease for 26.1% of patients. The median overall survival (OS) was 12 months. Multivariate analysis detected that factors associated with worse OS were age being >72 years old (HR 1.94), lymph nodal involvement (HR 2.01), metastatic disease (HR 2.04), and the size of the primary tumor being >44.5 mm (HR 1.80). In the N0M0 populations, the size of the primary tumor being <44.5 mm, age being <72 years old, and major surgery were independently associated with a lower risk of death. In the N+M0 group, the size of the primary lesion was the only factor to retain an association with OS. Conclusions: Our SEER database analysis evidenced prognostic factors for high-grade NEC of the bladder that are of pivotal relevance to guide treatment and the decision-making process.

Treatment Outcomes for Small Cell Carcinoma of the Bladder: Results From a UK Patient Retrospective Cohort Study

PURPOSE

Small cell carcinoma of the bladder (SCCB) is rare, accounting for less than 1% of all bladder carcinomas. It is aggressive, and outcomes are poor as a result of its early metastatic spread. Owing to its rarity, there are limitations on data to propose standardized management pathways.

METHODS AND MATERIALS

We conducted a retrospective analysis of patients presenting with pure or predominant-histology SCCB to 26 institutions in the United Kingdom between 2006 and 2016. The data cutoff date was February 1, 2018. We report patient characteristics, treatment received, and subsequent clinical outcomes.

RESULTS

A total of 409 eligible patients were included. Among these, 306 (74.8%) were male, the median age was 71 years (range, 35-96 years), and 189 patients (46.2%) had pure-histology SCCB. At data cutoff, 301 patients (73.6%) had died. The median overall survival (OS) was 15.9 months (95% CI, 13.2-18.7 months). Two hundred patients (48.9%) were confirmed to have bladder-confined disease (N0, M0), with a median OS of 28.3 months (95% CI, 20.9-35.8 months), versus a median OS of 12.7 months (95% CI, 10.9-14.6 months) for the 172 patients (42.1%) with confirmed N1-3 and/or M1 disease (hazard ratio [HR], 2.03; 95% CI, 1.58-2.60; P < .001). A total of 247 patients (61.5%) received primary chemotherapy, with a median OS of 21.6 months (95% CI, 15.5-27.6 months), versus a median OS of 9.1 months (95% CI, 5.4-12.8 months) in patients who did not receive primary chemotherapy (HR, 0.46; 95% CI, 0.37-0.59; P < .001). Choice of chemotherapy agent did not alter outcomes. For those with bladder-confined disease, 61 (30.5%) underwent cystectomy, and 104 (52.0%) received radiation therapy. Survival outcomes were similar for both cystectomy and radiation therapy. Only 6 patients (1.5%) were identified as having brain metastases at any time point.

CONCLUSIONS

To our knowledge, this is the largest retrospective study of all-stage SCCB to date. Patients have a poor prognosis overall, but survival is improved in those able to receive chemotherapy and with organ-confined disease. Brain metastases are rare.

Prognostic significance of non-urothelial carcinoma of bladder: analysis of nationwide hospital-based cancer registry data in Japan

OBJECTIVES

To identify the prognosis of pure non-urothelial carcinoma (non-UC) of bladder and to compare them with those of pure urothelial carcinoma (UC).

METHODS

We used Japan's nationwide hospital-based cancer registry data to extract histologically confirmed pure non-UC and UC cases of bladder diagnosed in 2008-2009. We estimated the 5-year overall survival (OS) by a Kaplan-Meier analysis.

RESULTS

A total of 8094 patients with confirmed histological subtypes of bladder cancer were identified. The most common pure non-UC was squamous cell carcinoma (SQ, n = 192, 2.4%) followed by adenocarcinoma (AC, n = 138, 1.7%) and small cell neuroendocrine carcinoma (SmC, n = 54, 0.7%). The proportion of female patients (48%) was significantly higher in the SQ group compared with the pure UC group (P < 0.001). The 5-year OS rate of the non-UC patients was significantly worse than that of the UC patients (40 vs. 61%, P < 0.001). According to stages, the 5-year OS rates of the stage I and III non-UC patients were significantly worse than those of the UC patients (P = 0.001). Considering histologic subtypes and stages, the 5-year OS rates of the stage I SQ patients were worse than those of the AC and SmC patients (46, 68 and 64%, respectively).

CONCLUSION

The prognosis of pure non-UC was worse than that of pure UC, especially in the stage I and III non-UC patients. To improve these patients' oncologic outcomes, a more aggressive surgical approach may be necessary in stage I patients with non-UC, especially in pure SQ.

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.