Clinical review – Small cell carcinoma of the bladder

Histopathologic Progression and Metastatic Relapse Outcomes in Small Cell Neuroendocrine Carcinomas of the Urinary Tract

INTRODUCTION

Small cell neuroendocrine carcinoma of the urinary tract (SCNEC-URO) has an inferior prognosis compared to conventional urothelial carcinoma (UC). Here, we evaluate the predictors and patterns of relapse after surgery.

MATERIALS AND METHODS

We identified a definitive-surgery cohort (n = 224) from an institutional database of patients with cT1-T4NxM0 SCNEC-URO treated in 1985-2021. Histopathologic review was conducted by independent pathologists. Relapse event was the time-to-event outcome, and relapse probabilities were estimated using a competing risk method with cumulative incidence functions (CIFs). Fine-Gray distribution models assessed covariate associations.

RESULTS

Most patients (161, 71.9%) received neoadjuvant chemotherapy (neoCTX). Ninety two (41%) patients had relapse with 77 (83.7%) having distant organs as first metastatic sites, including 10 (10.9%) with exclusive central nervous system (CNS) metastases, mostly (9/10) within 1 year of surgery. Patients with pathologic complete response (pCR) after neoCTx had the lowest 5-year CIF (16.5% [95% CI 9.3%-25.6%]). Patients with remaining exclusively small cell (SC) histology had the highest CIF (85.7% [95% CI 46.6-96.9]). Patients with eradicated SCNEC but remaining UC components had an intermediate-risk CIF (32.5% [95% CI 18.6-47.2]). Multivariable analysis adjusting for neoCTx, clinical stage at diagnosis (T3/4, N0/N+ vs. T1/T2, N0), and pathologic stage (pN+ vs. pN0) demonstrated that any SCNEC histology at resection (vs. pCR) was associated with relapse risk (hazard ratio = 3.69 [95% CI 1.91-7.13], p = 0.0001).

CONCLUSIONS

SCNEC-URO is a systemic disease with high risk of distant relapse including CNS. Our findings highlight unmet needs for neoadjuvant/adjuvant approaches targeting the rare SCNEC subtype and suggest adding CNS surveillance within the first year after definitive surgery to high-risk patients. PRÉCIS (CONDENSED ABSTRACT): Alongside neoadjuvant chemotherapy and cancer stage, histology at resection strongly impacts relapse risk in small cell neuroendocrine carcinomas of the urinary tract. The incidence of brain metastasis is notably higher than in "traditional" urothelial cancer within the first year after surgery, especially if small cell cancer persists, thus necessitating close neurological monitoring during this period.

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.

CT and MRI findings of small cell neuroendocrine carcinoma of the urinary bladder: comparison with urothelial carcinoma

OBJECTIVE

This study aimed to evaluate the efficacy of CT and MRI findings to differentiate small cell neuroendocrine carcinoma (SCNEC) from urothelial carcinoma (UC) of the urinary bladder.

MATERIALS AND METHODS

This study included 90 patients with histopathologically confirmed bladder cancer (10 SCNECs and 80 UCs). Eight patients with bladder SCNEC and 80 with UC underwent CT and MRI, whereas the remaining two patients with SCNEC underwent CT alone before treatment. CT and MRI findings were retrospectively evaluated and compared between the two pathologies.

RESULTS

The maximum diameter (36.5 mm vs. 19.0 mm, p < 0.01) and height (22.0 mm vs. 14.0 mm, p < 0.01) of the tumor in bladder SCNEC were higher than in UC. The pedunculated configuration (20% vs. 61%, p < 0.05) and irregular tumor margins (20% vs. 76%, p < 0.01) in bladder SCNEC were less common than in UC. The CT attenuation of the solid component in unenhanced CT images was higher in bladder SCNEC than in UC (37 Hounsfield unit [HU] vs. 34 HU, p < 0.01). The apparent diffusion coefficient (ADC) of the solid component in bladder SCNEC was lower than in UC (0.49 × 10-3 mm2/s vs. 1.02 × 10-3 mm2/s, p < 0.01).

CONCLUSION

In comparison with UC, bladder SCNEC was larger, had higher unenhanced CT attenuation, and had a lower ADC value. The pedunculated configuration and irregular tumor margins were typical of bladder UC.

Emerging Insights in Small-Cell Carcinoma of the Genitourinary Tract: From Diagnosis to Novel Therapeutic Horizons

Small-cell carcinomas (SCCs) of the genitourinary (GU) tract are rare malignancies with high metastatic potential. The most common primary sites are the bladder and prostate, but case reports of primary SCC of the kidney, ureter, and urethra also exist. The majority of patients present with gross hematuria, irritative or obstructive urinary symptoms, and symptoms of locoregionally advanced or metastatic disease at initial presentation. SCC of the bladder presents with nodal or metastatic involvement in the majority of cases and requires the use of platinum-based chemotherapy in combination with surgery and/or radiation. SCC of the prostate is most commonly seen in the metastatic castrate-resistant setting, and aggressive variant disease presents with a greater propensity for visceral metastases, osteolytic lesions, and relatively low serum prostate-specific antigen for volume of disease burden. Multiple retrospective and prospective randomized studies support the use of a multimodal approach combining platinum-based systemic therapy regimens with radiation and/or surgery for localized disease. This evidence-based strategy is reflected in multiple consensus guidelines. Emerging data suggest that small-cell bladder and prostate cancers transdifferentiate from a common progenitor of conventional urothelial bladder carcinoma and prostatic acinar adenocarcinoma, respectively. Areas of active basic research include efforts to identify the key genetic and epigenetic drivers involved in the emergence of small cell cancers to exploit them for novel therapies. Here, we review these efforts, discuss diagnosis and currently supported management strategies, and summarize ongoing clinical trials evaluating novel therapies to treat this rare, aggressive GU cancer.

Unusual histomorphological spectrum of urinary bladder cancers and their treatment modalities revisited: Our experience with series of five cases

Background

Urinary bladder cancer is the eighth-most frequent carcinoma in men, commonly occurs in elderly male. Major risk factors are smoking, chronic cystitis, urinary stones. The most common histologic variant of bladder cancer is urothelial carcinoma (UC), but certain variants are unusual yet aggressive for which there is no consensus guideline of therapy. Those entities include neuroendocrine tumors both primary and metastatic, squamous cell carcinoma, and sarcomatoid carcinoma. Neuroendocrine tumors comprise carcinoid, small-cell carcinoma, and large-cell carcinoma.

Aim

The present study is undertaken to highlight certain biological features of these unusual aggressive histological forms of bladder carcinoma and their recent treatment modality to prevent recurrence, metastasis, upgrading of tumor stage, and enable surprisingly complete remission.

Methods

This piece of hospital-based perspective study was done from June 2018 to May 2020. Both transurethral resection of bladder tumor and cystectomy surgical samples of the symptomatic patients were collected from the urology department of our institute along with demographic data. Then processed, stained in both routine H and E stain and immunohistochemical stains (Immunohistochemistry [IHC]) like PanCK, NSE, synaptophysin, chromogranin, etc.

Results

Total number of bladder cancer encountered was 42 cases; of these five rare variants were observed, i.e., one case each of primary and secondary small cell neuroendocrine carcinoma, one large cell carcinoma, one squamous cell carcinoma (SCC), and one case of sarcomatoid carcinoma. Histomorphology with IHC conferred the diagnosis then multimodality therapy (neoadjuvant/radiotherapy/surgery) was installed and followed up.

Conclusion

The unconventional forms of UC can be easily diagnosed by histomorphology and can have better survival with the help of the recent multimodal treatment approach.

Neuroendocrine tumors of the urinary system: literature review

Most often, neuroendocrine carcinoma (NEC) is found in the gastrointestinal tract, broncho-pulmonary system, but they can also occur in other organs, such as the kidney, bladder, which is of most interest because of the rarity of this pathology. Until recently, there was not even a proper morphological classification for kidney NEC, and among some histological types, such as large cell neuroendocrine carcinoma of the kidney, only about 7 cases were recorded, and independent bladder carcinoids, about 15 cases. Currently, there are no clinical and morphological features of the NEC of the kidney and bladder, fundamentally distinguishing them from other neuroendocrine tumors and “classic” cancer of the same localization. This article also provides the data of the N.N. Blokhin National Medical Research Centre of Oncology on the incidence of all malignant neoplasms of the urinary system.

Connexins and Gap Junctions in Cancer of the Urinary Tract

This review focuses on connexins and nexus or gap junctions in the genesis, progression, and therapy of carcinomas of the human urinary tract. Some decades ago, the idea was born that gap junctional intercellular communication might prevent both the onset and the progression of cancer. Later evidence indicated that, on the contrary, synthesis and the presence of connexins as a prerequisite for gap junctional intercellular communication might promote the occurrence of cancer and metastases. The research history of urinary bladder cancer is a good example of the development of scientific perception. So far, the role of gap junctional intercellular communication in carcinogenesis and cancer progression, as well as in therapeutical approaches, remains unclear.

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.

Systematic review and two new cases of primary upper urinary tract neuroendocrine carcinomas

BACKGROUND

Upper urinary tract neuroendocrine carcinoma (UUT-NEC) is extremely rare and has a poor prognosis. Although a few cases of successful treatment have been reported, no treatment has shown established efficacy.

PATIENTS AND METHODS

We analyzed 70 UUT-NEC patients, including 68 with small cell neuroendocrine carcinoma (SCNEC) and large cell neuroendocrine carcinoma (LCNEC) reported between 1985 and 2017 and 2 treated at our hospital.

RESULTS

Median patient age was 66 years, 58.6% were men, and 60% were of Asian descent. Most UUT-NECs were SCNEC (68; 95.7%), whereas LCNEC was very rare (2; 2.9%). More than half of the patients had accompanying other histological components, the most common being urothelial carcinoma (51.5%), whereas 41.4% had NEC alone. Of the 70 patients, 27 underwent additional therapy (e.g., chemotherapy and radiotherapy) along with surgery. Median survival was 15 months. In univariate analysis, stages T1-2 disease showed better prognosis than stages T3-4 (P < 0.001). Additional treatment (e.g., chemotherapy and radiotherapy) significantly improved prognosis (P = 0.014). Moreover, platinum-based chemotherapy also was associated with improved prognosis (P = 0.017). For platinum-based chemotherapy, multicollinearity with additional treatments was strong, and, thus, these data were not included in the analysis. Multivariate analysis revealed pathological stage (T1-2 vs. T3-4; P = 0.003) and additional treatment (P = 0.028) to be independent predictors of improved prognosis.

CONCLUSION

Although UUT-NEC has a poor prognosis, additional treatment along with surgery and therapeutic intervention and stage T1-2 disease are independent factors to improve prognosis.

Primary small cell carcinoma of the ureter: Case report and review of the literature

RATIONALE

Primitive small cell carcinoma of the ureter is extremely rare, in this case report is meticulously described its aggressive clinical course and the pathological clues that help with the diagnosis. Also, a detailed table with the clinico-pathological features of analogous case reports in literature is provided.

PATIENT CONCERNS

A 79-year-old female presented with gross hematuria and flank pain.

DIAGNOSES

Small cell carcinoma of the ureter. The surgical specimen showed a mixed histology of small cell carcinoma and transitional cell carcinoma; the common neuroendocrine markers (chromogranin A, synaptophysin, CD56) were positive, and vimentin and thyroid transcription factor 1 were negative. The patient had an advanced stage at presentation with regional nodes involvement (pT3N1).

INTERVENTIONS

Segmental ureterectomy was performed but it was only possible to administer 1 cycle of platinum-based adjuvant chemotherapy due to the rapid decline of her clinical parameters.

OUTCOMES

The disease rapidly spread locally and metastasized.

LESSON

The clinicians must be aware of this aggressive tumor with silent clinical course and advanced stages at presentation.

Neuroendocrine bladder cancer: oncological emergency?

Neuroendocrine bladder cancer is extremely rare, with an estimated incidence of 0.5%- 0.7%. In bladder cancers there is no evident connection between the neuroendocrine phenotypic expression and the clinical history. However, prognosis is usually poor and the survival rate at 5 years does not exceed 8%, if untreated.

Methods.

We are here describing three case reports of bladder carcinoma with neuroendocrine differentiation, which is extremely aggressive and leads rapidly to death. At the present time, the local control of these tumors is achieved by radical cystectomy and radiotherapy; they can be both associated to chemotherapy. However, since these lesions are fairly rare, there is no gold standard therapy and there are no prospective studies on the management of these tumors.

Conclusions.

Considering the quick evolution and progression of any variant of the neuroendocrine tumors of the bladder, urologists and anesthetists should see them as real oncological emergencies. A prompt intervention through radical surgery with cystectomy and linfadenectomia, and the anathomo-pathologist's systematic investigation of the scraps could make the approach therapeutic and not only palliative. Prospective studies on neo-adjuvant chemotherapy as well as experimental studies about target therapies may yield new guidelines on the tumor management.

External Beam Radiation and Brachytherapy for Prostate Cancer: Is It a Possible Trigger of Large Cell Neuroendocrine Carcinoma of the Urinary Bladder?

Neuroendocrine tumors commonly involve the respiratory and gastrointestinal systems. Primary genitourinary neuroendocrine tumors are rare, accounting for less than 1% of all bladder carcinomas. Four histopathologic subtypes have been described. Among those, large cell neuroendocrine carcinoma (LCNEC) is the least common, is more aggressive, and generally presents in an advanced stage with poor prognosis compared to transitional cell bladder carcinoma. There is no standardized treatment regimen because of the rarity of the disease. Herein, we present a case of 72-year-old male patient with previously treated prostate cancer, who received external beam radiation therapy and high dose brachytherapy, presenting with intermittent hematuria. Cystoscopy and transurethral resection of bladder tumor (TURBT) were performed. The histopathology and immunohistochemistry were consistent with large cell neuroendocrine carcinoma (LCNEC). Further studies are required to proof the higher risk of neuroendocrine carcinoma of the bladder in patients treated with external beam radiation therapy and brachytherapy for prostate cancer.

Neuroendocrine Tumor of the Ureter: A Zebra Among Horses

Primary neuroendocrine tumors of the upper urinary tract are extremely rare. We report a case of de novo small cell carcinoma of the ureter that presented masquerading as a distal ureteral stone. A 55-year-old lady presented to our clinic with 1 month history of right lower back pain and hematuria. Her history was notable for stage 1B mixed clear cell-endometroid cancer of the uterus status post radical abdominal hysterectomy with adjuvant radiotherapy, 7 years before the current episode. The patient had no evidence of recurrence. Initial noncontrast imaging suggested a 2.5 mm calculus in the distal right ureter and hydronephrosis; however, ureteroscopy revealed a large fleshy mass at the location. Histopathologic evaluation demonstrated the lesion to be primary small cell carcinoma of the ureter, without evidence of it being a derivative of the prior gynecologic malignancy. Metastatic work-up revealed high burden retroperitoneal adenopathy. The patient was started on Cisplatin-based neoadjuvant chemotherapy with plan for nephroureterectomy in the future. At 3 months follow-up, the patient was doing well with significant shrinkage of retroperitoneal adenopathy and no evidence of disease progression.

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.

Primary Small Cell Carcinoma in Urinary Bladder: A Rare Case

Small cell carcinoma of bladder, which does not have a common and accepted treatment protocol, is a rare and highly aggressive tumor. It is mostly pulmonary originated; however, it can rarely be seen in extrapulmonary sites. We presented an interesting and uncommon case, in which the transitional cell tumor was found in the transurethral resection specimen, but the small cell carcinoma was detected in the final radical cystectomy material.

Small cell carcinoma of the urinary bladder without gross hematuria: a case report

Small cell carcinoma of the urinary bladder (SCCB) is a rare and aggressive form of bladder cancer with poor prognosis. Hematuria is the main symptom of this malignancy, and most patients have a history of smoking. The disease incidence of malignant bladder tumors in China is approximately 0.74%. Early and accurate diagnosis of SCCB can ensure timely and appropriate treatment of this malignant disease. Oncologic surgery is the standard treatment; however, it may not be a curative approach. Chemotherapy and/or radiotherapy should be performed following surgical removal. This case report describes a patient with a single neoplasm diagnosed as SCCB that arose because of recurrence of bladder cancer after bladder tumor resection. In contrast to previously reported cases, this patient had no gross hematuria and no history of smoking.

Small cell carcinoma of the bladder

Small cell carcinoma of the urinary bladder is an extremely aggressive and rare tumor. Even though small cell carcinoma most commonly arises from the lungs there are several reports of small cell carcinoma in extrapulmonary sites. Due to its low frequency there is no well-established management for this disease. We report the case of a 61 year-old man with small cell carcinoma of the bladder who underwent radical cystectomy following neoadjuvant chemotherapy. We also reviewed the literature for the optimal treatment strategy.

Small cell carcinoma of the urinary bladder: a contemporary review with a special focus on bladder-sparing treatments

Small cell carcinoma of the urinary bladder (SCCUB) is a rare and aggressive disease. To date, no standard treatment has been proposed due to the lack of prospective studies resulting from the rarity of this disease. Recently published studies of relatively large patient cohorts, however, have shed some light on the management of SCCUB patients. In this article, the authors review the epidemiology, pathogenesis, diagnosis and treatment (based on disease stage), and they then discuss the optimal therapeutic strategy for SCCUB patients, particularly for those with limited, locoregional disease. The authors conclude that multidisciplinary approaches are needed for the optimal management of this aggressive disease. The authors also discuss bladder-sparing approaches for SCCUB patients, compared to those for conventional bladder urothelial carcinoma patients.

Large cell neuroendocrine carcinoma of the urinary bladder: case report and review

INTRODUCTION

Neuroendocrine carcinomas of the urinary bladder are relatively rare, accounting for less than 1% of all bladder carcinomas. These tumors can be divided into the more indolent typical or atypical carcinoid tumors and the aggressive small cell and large cell neuroendocrine carcinomas.

OBJECTIVE

To report 2 clinical cases of large cell neuroendocrine carcinoma of the bladder (LCCB) and to review the epidemiology, prognosis, and current treatment algorithms for patients with bladder small and large cell neuroendocrine carcinomas.

RESULTS

In both cases hematuria was the presenting symptom. One patient was submitted to partial cystectomy and the other to trans-urethral resection of the bladder tumor. The former patient died on the third month postoperatively. The latter patient had extensive liver metastasis at the time of diagnosis and died from acute liver failure on the 14th postoperative day. In review LCCB is associated with a more aggressive behavior and poorer prognosis than transitional cell bladder carcinoma. No standard approach exists. Surgery (transurethral ressection, partial cystectomy, radical cystectomy), chemotherapy and radiotherapy are current treatment modalities.

CONCLUSION

LCCB is an aggressive tumor which usually presents itself in an advanced stage. Neoadjuvant chemotherapy with platinum regimen plus aggressive surgical approach should be the treatment of choice.

Pure primary small cell carcinoma of urinary bladder: A rare diagnostic entity

Small cell carcinoma of the bladder is a rare, aggressive, poorly differentiated neuroendocrine neoplasm accounting for only 0.3-0.7% of all bladder tumors. Since the tumor is very rare, pathogenesis is uncertain. Small cell carcinomas of the urinary bladder are mixed with classic urothelial carcinomas or adenocarcinomas of the bladder in 68% cases, making pure primary small cell carcinoma even a rarer entity. The unknown etiology and natural history of small cell carcinoma of the urinary bladder represent a challenge both to the pathologist and urologists for its diagnosis and treatment, respectively.

Small cell neuroendocrine carcinoma of the urinary tract successfully managed with neoadjuvant chemotherapy

Introduction. Small cell neuroendocrine carcinomas of the urinary tract is an extremely rare entity and very few cases have been reported in the literature. Small cell neuroendocrine carcinoma of the urinary tract (SCC-UT) is the association between bladder and urinary upper tract-small cell carcinoma (UUT-SCC). It characterized by an aggressive clinical course. The prognosis is poor due to local or distant metastases, and usually the muscle of the bladder is invaded. Case Presentation. We report a rare case of a 54-year-old Arab male native of moroccan; he is a smoker and was referred to our institution for intermittent hematuria. Following a diagnosis of small cell neuroendocrine carcinomas of the ureter and the bladder, thoracoabdominal-pelvic CT was done, and the staging of the tumor was done in the bladder (T2N0M0) and (T1N0M0) in the ureter. Neoadjuvant alternating doublet chemotherapy with ifosfamide/doxorubicin and etoposide/cisplatin was realized, and nephroureterectomy associated to a cystoprostatectomy was carried out. After 24 months of followup, no local or distant metastasis was detected. Conclusion. The purpose of this review is to present a rare case of pure small cell neuroendocrine carcinoma of the urinary tract and review the literature about the place of neoadjuvant chemotherapy in this rare tumors.

Clinical outcome of primary small cell carcinoma of the urinary bladder

Purpose

Primary small cell carcinoma of the urinary bladder is a rare malignant disease. It accounts for less than 1% of all urinary bladder carcinomas. The purpose of this study is to review the clinical features, the treatment modalities, and the overall survival of these patients. We also compare the clinical outcomes between patients of bladder small cell carcinoma (SCC) and bladder urothelial carcinoma (UC).

Materials and methods

We reviewed the charts of patients with bladder tumors from January 1995 to December 2012 in the Chang Gung Memorial Hospital. A total of 2421 malignant bladder tumor patients were reviewed and there were 18 patients who were diagnosed with primary bladder SCC. The patients’ characteristics, including age, gender, smoking history, presented symptoms, tumor size, locations, clinical stages, treatment modalities, pathology appearance, recurrence conditions, and survival conditions were all recorded. We also compared the clinical outcomes and the overall survival rates between patients with bladder SCC and those with UC.

Results

Bladder SCC accounted for about 0.74% of all bladder malignancies in our institution. The mean age at diagnosis was 70.67 years, and the male-to-female ratio was 2.6:1. Thirteen patients had a history of cigarette smoking. All patients presented with symptoms of gross hematuria, and three of them had bladder tamponade requiring blood clot evacuation by cystoscopy. Only one patient had T1 disease, ten patients had stage III disease, and seven patients had lymph node or distant metastasis (stage IV disease). The mean tumor size was 4.29 cm in diameter. For the majority (61.11%) of patients, SCC coexisted with UC components. The average survival time was 10.92 months. Patients with bladder SCC had worse overall survival rates than those of stage III and stage IV bladder UC. Performing radical cystectomy does not significantly improve their overall survival rates. None of the clinicopathologic parameters, including the presence of coexisting nonsmall cell carcinoma component (P = 0.831), receiving radical cystectomy (P = 0.194), distant metastasis (P = 0.062), and gender (P = 0.564), were significantly associated with survival.

Conclusion

SCC of the urinary bladder is a rare condition, and standard treatment outlines have not been well established. Most of the presented cases have a very poor prognosis. Prospective, multi-institutional, randomized studies are required to assess better treatment modalities. To the best of our knowledge, this is the largest reported case analysis of primary bladder SCC in a Taiwanese population.

Metastatic primary neuroendocrine carcinoma of the genitourinary tract: A case report of an uncommon entity

Patient:

Male, 59

Final Diagnosis:

Neuroendocrine carcinoma of urinary bladder

Symptoms:

Dysuria • hematuria

Medication:

–

Clinical Procedure:

MRI • cystoscopy

Specialty:

Urology • oncology

Objective:

Rare disease

Background:

Neuroendocrine carcinomas of the genitourinary tract are rare but distinct and important entities because they are very aggressive tumors and are usually advanced or metastatic at the time of diagnosis. A high index of suspicion must be held by the pathologist viewing the specimen, as it can easily be misdiagnosed as a high grade urothelial carcinoma. Specific, proven treatment algorithms have been formulated over the years for the latter, whilst neuroendocrine carcinomas of the genitourinary tract are rare and treatment regimes have not yet been proven to show a significant improvement in survival in the majority of cases, so accurate diagnosis is important.

Case Report:

We report the case of a 59-year-old man who presented with a short history of dysuria and frank hematuria. Imaging and cystoscopy revealed a large exophytic mass in the base of the urinary bladder, which extended into the bladder neck. Metastatic deposits were already present in his liver and vertebrae. Histology revealed a neuroendocrine carcinoma.

Conclusions:

A comprehensive review of the existing literature regarding this rare but aggressive tumor is presented, including advances in classification, pathogenesis, and treatment.

Small cell carcinoma of the urinary bladder: a rare, aggressive neuroendocrine malignancy

Small cell carcinoma of the urinary bladder is a rare, often fatal, disease. Its presenting symptoms and gross morphology are similar to those of conventional urothelial carcinoma, whereas its prognosis is much poorer with frequent metastasis. Small cell carcinoma of the urinary bladder shares similar histology with its counterparts in other organs; however, its immunoreactivity to conventional neuroendocrine markers is low. Its diagnosis is thus considered permissible on morphologic grounds alone. Multimodal treatments are often employed, although no definite treatment algorithm has been established. For this extremely aggressive malignancy with an as-yet inconclusive etiology, further studies are needed to clarify its molecular pathogenesis to serve as a basis for diagnostic markers and therapeutic targets. The clinical, morphologic, immunoreactive, molecular, and therapeutic features of bladder small cell carcinoma are reviewed, including a detailed discussion on the utility of immunohistochemical markers.

Primary mixed neuroendocrine carcinoma of the bladder with large cell component: a case report and review of the literature

Primary large cell neuroendocrine carcinomas (NECs) of the bladder are rarely encountered, and only a few reports have been documented. Frequently, they are found to be admixed with other histologies. In this report, we describe such a tumor found in a 65-year-old man who underwent radical cystectomy, after initial transurethral resection discovered a small cell NEC pathology. We also reviewed the limited number of neuroendocrine tumors reported containing a large cell component. Given the paucity of these tumors and the resultant difficulty in developing generalized treatment protocols, we promote the use of gene expression models to tailor chemotherapeutic regimens for individual tumors.

A rare bladder cancer--small cell carcinoma: review and update

Small cell carcinoma of the bladder (SCCB) is rare, highly aggressive and diagnosed mainly at advanced stages. Hematuria is the main symptom of this malignancy. The origin of the disease is unknown; however the multipotent stem cell theory applies best to this case. Histology and immunohistochemistry shows a tumour which is indistinguishable from small cell lung carcinoma (SCLC). Coexistence of SCCB with other types of carcinoma is common. The staging system used is the TNM-staging of bladder transitional cell carcinoma. The treatment is extrapolated from that of SCLC. However, many patients with SCCB undergo radical resection which is rarely performed in SCLC. Patients with surgically resectable disease (< or = cT1-4aN0M0) should be managed with multimodal therapy associating chemotherapy, surgery and/or radiotherapy. Neoadjuvant chemotherapy using four chemotherapy cycles followed by radical cystectomy is the most effective therapeutic sequence. Patients with unresectable disease (> or = cT4bN+M+) should be managed with palliative chemotherapy based on neuroendocrine type regimens comprising a platinum drug (cisplatin in fit patients). The prognosis of the disease is poor mainly in the case of pure small cell carcinoma. Other research programs are needed to improve the outcome of SCCB.

Small cell carcinoma of the upper urinary tract (UUT-SCC): report of a rare entity and systematic review of the literature

BACKGROUND

Primary small cell carcinoma of the upper urinary tract (UUT-SCC) is an extremely uncommon disease. The current knowledge of these rare tumors is mainly based on case reports or small series.

METHODS

We reported two cases and performed a systematic literature search from 1970 to 2010 for articles on UUT-SCC. Overall, 40 patients with UUT-SCC were reviewed, a database was generated to analyze clinical characteristics, pathological features and therapy outcomes and to attempt in identifying prognostic factors.

RESULTS

For the 39 cases with available data, median age was 66.5 years and male-female ratio was 2:1. An Asian ethnic background was more common (59%). Surgery was the standard treatment given to all patients. In 67% of cases, SCC coexisted with another malignant component, including urothelial carcinoma in 62% of patients. Overall median survival was 15 months and the 1-, 2- and 3-year survival rates were 58.4%, 38.1% and 23.8%, respectively. Of all cases, 53.8% developed detectable metastasis in a median delay of 13 months. Pathological stage was the only significant prognostic factor found (p=0.01). Patients who received adjuvant chemotherapy seem to have a higher median survival comparatively to those who did not receive chemotherapy but this was not statistically significant (24 vs. 12 months, p=0.56).

CONCLUSIONS

UUT-SCC is an extremely rare tumor characterized by an aggressive clinical course. Local or distant metastases are frequent and survival is poor. Pathological stage appeared to be a prognostic factor for overall survival.

Role of carbonate in the cytotoxicity of carboplatin

Carboplatin, [Pt(NH3)2(CBDCA-O,O')], 1, where CBDCA is cyclobutane-1,1-dicarboxylate, is used against ovarian, lung, and other types of cancer. We recently showed (Di Pasqua et al. (2006) Chem. Res. Toxicol. 19, 139-149) that carboplatin reacts with carbonate under conditions that simulate therapy to produce carbonato carboplatin, cis-[Pt(NH3)2(O-CBDCA)(CO3)]2-, 2. We use 13C and 1H NMR and UV-visible absorption spectroscopy to show that solutions containing carboplatin that have been aged in carbonate buffer under various conditions contain 1, 2, and other compounds. We then show that aging carboplatin in carbonate produces compounds that are more toxic to human neuroblastoma (SK-N-SH), proximal renal tubule (HK-2) and Namalwa-luc Burkitt's lymphoma (BL) cells than carboplatin alone. Moreover, increasing the aging time increases the cytotoxicity of the platinum solutions as measured by the increase in cell death. Although HK-2 cells experience a large loss in survival upon exposure to carbonato forms of the drug, they have the highest values of IC50 of the three cell lines studied, so that HK-2 cells remain the most resistant to the toxic effects of the carbonato forms in the culture medium. This is consistent with the well-known low renal toxicity observed for carboplatin in therapy. The uptake rates for normal Jurkat cells (NJ) and cisplatin-resistant Jurkat cells (RJ), measured by inductively coupled plasma mass spectrometry (ICP-MS), are 16.6 +/- 4.2 and 12.3 +/- 4.8 amol of Pt h-1 cell-1, respectively, when exposed to carboplatin alone. However, when these cells are exposed to carboplatin that has been aged in carbonate media, normal Jurkat cells strongly bind/take up Pt at a rate of 14.5 +/- 4.1 amol of Pt h-1 cell-1, while resistant cells strongly bind/take up 5.1 +/- 3.3 amol of Pt h-1 cell-1. Collectively, these studies show that carboplatin carbonato species may play a major role in the cytotoxicity and uptake of carboplatin by cells.