Neoadjuvant Chemotherapy in Neuroendocrine Bladder Cancer: A Case Report

Neuroendocrine Carcinoma of the Urinary Bladder: CT Findings and Radiomics Signature

Background: We present a case series of Neuroendocrine Carcinoma of the Urinary Bladder (NECB) to analyse their radiologic appearance on CT, find a "Radiomic signature", and review the current literature. Methods: 14 CT cases of NECB were reviewed and compared with a control group of 42 patients with high-grade non-neuroendocrine bladder neoplasm for the following parameters: ring enhancement; implantation site; dimensions; density; margins; central necrosis; calcifications; number of lesions; wall thickness; depth of invasion in the soft tissue; invasion of fat tissue; invasion of adjacent organs; lymph-node involvement; abdominal organ metastasis. To extract radiomic features, volumes of interest of bladder lesions were manually delineated on the portal-venous phase. The radiomic features of the two groups were identified and compared. Results: Statistical differences among NECB and control group were found in the prevalence of male sex (100% vs. 69.0%), hydronephrosis (71.4% vs. 33.3%), mean density of the mass (51.01 ± 15.48 vs. 76.27 ± 22.26 HU); product of the maximum diameters on the axial plane (38.1 ± 59.3 vs. 14.44 ± 12.98 cm2) in the control group, trigonal region involvement (78.57% vs. 19.05%). About the radiomic features, Student's t-test showed significant correlation for the variables: "DependenceNonUniformity" (p: 0.048), "JointAverage" (p: 0.013), "LargeAreaLowGrayLevelEmphasis" (p: 0.014), "Maximum2DDiameterColumn" (p: 0.04), "Maximum 2DDiameterSlice" (p: 0.007), "MeanAbsoluteDeviation" (p: 0.021), "BoundingBoxA" (p: 0.022) and "CenterOfMassB" (p: 0.007). Conclusions: There is a typical pattern (male patient, large mass, trigonal area involvement) of NECB presentation on contrast-enhanced CT. Certain morphological characteristics and encouraging results about Radiomic features can help define the diagnosis.

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.

Giant bladder stone with squamous cell carcinoma of bladder: Case report and the literature review

INTRODUCTION AND IMPORTANCE

Concurrent bladder neoplasm and giant bladder stone are rare in contemporary urological practice. Squamous cell carcinoma (SCC) is rare histologic diagnosis of bladder cancer.

CASE PRESENTATION

A 45 y.o. male, with lower abdominal pain when urinating, that comes and goes in the last 35 years. He had gross hematuria a year ago. The patient comes from a rural region, which undiagnosed for years. Physical examination showed a suprapubic abdominal solid mass, sized 20 × 10 cm, without tenderness. On plain radiography, showed radiopaque lesion which fully occupies the bladder. The ultrasound showed bilateral hydronephrosis. The patient underwent vesicolithotomy, and a giant bladder stone (size of 14 × 9 cm) was found, with incidental finding of suspicious malignant mass. The patient refuses radical cystectomy. Due to mass characteristics that are manageable for complete excision and the need for histopathological studies, bladder preservative therapy was applied with complete tumor excision and biopsy. The mass pathological diagnosis is grade 2 squamous cell carcinoma with lamina muscularis invasion, staged pT3bN0M0. The patient underwent cisplatin-based chemotherapy, with regular evaluation. The possibility of future radical cystectomy remains open.

CLINICAL DISCUSSION

By diameter, the stones found in our patient is perhaps one of the largest that ever reported being associated with bladder SCC. The bladder stones causing chronic mucosal injury, lead to the development of SCC. In limited situation, bladder preservation therapy may be considered for muscle-invasive bladder cancer.

CONCLUSION

Despite its rarity, SCC along with the chronic bladder stone is possible, and needs more attention.

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.