A case of large cell neuroendocrine carcinoma of the bladder with prolonged spontaneous remission

Large-cell neuroendocrine carcinoma of the bladder: A case report

BACKGROUND

Bladder neuroendocrine tumors are few and exhibit a high degree of aggressiveness. The bladder is characterized by four distinct forms of neuroendocrine tumors. Among them, large-cell neuroendocrine carcinoma is the least prevalent, but has the highest level of aggressiveness. The 5-year survival rate for large-cell neuroendocrine carcinoma of the bladder is exceedingly poor. To date, only a few dozen cases have been reported.

CASE SUMMARY

Here, we report the case of a 65-year-old man with large-cell neuroendocrine carcinoma of the bladder. The patient presented to the Department of Urology at our hospital due to the presence of painless hematuria without any identifiable etiology. During hospitalization, abdominal computed tomography revealed the presence of an irregular mass on the right anterior wall of the bladder. A cystoscopic non-radical resection of the bladder lesion was performed. The postoperative pathological examination revealed large-cell neuroendocrine bladder cancer. Previous reports on cases of large-cell neuroendocrine carcinoma cases were retrieved from PubMed, and the present paper discusses the currently recognized best diagnostic and treatment options for large-cell neuroendocrine carcinoma based on the latest research progress.

CONCLUSION

Large-cell neuroendocrine carcinoma of the bladder is an uncommon malignancy with a highly unfavorable prognosis. Despite ongoing efforts to prolong patient survival through multidisciplinary therapy, the prognosis remains unfavorable. Large-cell neuroendocrine carcinoma continues to be a subject of uncertainty.

Unusual Association of Large Cell Neuroendocrine Carcinoma of the Bladder and Prostatic Adenocarcinoma Within a 76-Year-Old Man

Large cell neuroendocrine carcinoma (LCNEC) is one of the rarest types of bladder cancer, with an aggressive course and a poor prognosis. We report a case of LCNEC of the bladder associated with a prostatic adenocarcinoma. A very rare association, to our knowledge, is described for the first time in the literature. The patient was a 76-year-old non-smoker male, who presented with intermittent hematuria and dysuria. Cystoscopy revealed a lesion on the right lateral bladder wall. Biopsy was in favor of a LCNEC with muscle invasion. The CT scan showed the presence of a second lesion in the prostate, confirmed by histological examination. The patient was treated by neoadjuvant chemotherapy of the cisplatin-etoposide type for large-cell bladder neuroendocrine carcinoma, and hormone therapy with luteinizing hormone-releasing hormone (LH-RH) analogs for prostatic adenocarcinoma, followed by radical surgery. Given the rarity of this tumor, LCNEC treatment lacks precision. Many cases are published with different therapeutic strategies. A literature review would be interesting to codify the therapeutic strategy for this rare tumor.

Primary pure large cell neuroendocrine carcinoma of the urinary bladder: a case report and literature review

Background

The large cell neuroendocrine carcinoma (LCNEC) of the urinary bladder is a rare malignancy. With its high aggressiveness and poor prognosis, the disease is often accompanied by metastasis or recurrence. The lack of specific clinical manifestations and imaging features causes considerable challenges for clinical diagnosis and treatment.

Case presentation

We report a case of LCNEC of the urinary bladder. The patient was a 79-year-old male admitted to our hospital with recurrent episodes of asymptomatic gross hematuria. Based on the computed tomography (CT) scan findings, our patient presented with a bladder mass displaying invasion into the serosal layer, suggestive of muscle involvement and indicative of malignancy. The patient received a radical cystectomy, and the postoperative pathology confirmed primary, pure LCNEC of the urinary bladder. We gave him 16 cycles of toripalimab immunotherapy. As of follow-up, the patient was alive, and periodic CT reexamination showed no evidence of recurrence.

Conclusions

We reviewed domestic and foreign literature and found no explicit treatment protocols exist for the disease. Surgical resection combined with chemotherapy were the most common treatments. Herein, we reported the first case of primary, pure LCNEC of the urinary bladder treated by radical cystectomy combined with pure immunotherapy, achieving sustained remission, which provides a new idea for the immunotherapy and integrative treatment of the disease.

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.

Primary MiNEN of the urinary bladder: an hitherto undescribed entity composed of large cell neuroendocrine carcinoma and adenocarcinoma with a distinct clinical behavior : Description of a case and review of the pertinent literature

Neuroendocrine carcinomas (NECs) of the urinary bladder are very rare and can be observed in the context of mixed neuroendocrine/non-neuroendocrine neoplasms (MiNENs), most frequently in association with urothelial carcinoma. Small cell NECs are far more common than large cell NECs (LCNECs), which are exceedingly rare. We describe a primary MiNEN of the urinary bladder, composed of a LCNEC and of an adenocarcinoma, in which the neuroendocrine component reached complete pathological regression after neoadjuvant M-VAC chemotherapy, whereas the non-neuroendocrine component of the tumor progressed to metastatic disease. Compared to mixed neuroendocrine/non-neuroendocrine neoplasms described in the literature until now, this appears to be a unique case that expands the spectrum of neuroendocrine neoplasia of the urinary bladder.

Large Cell Neuroendocrine Carcinoma of the Bladder with Adenocarcinomatous Component

Large cell neuroendocrine carcinoma (LCNC) is one of the rarest types of bladder cancer occurring in <1%. Either pure or mixed with another component, it remains one of the most aggressive types of bladder cancer. We report a case of LCNC of the bladder with an adenocarcinomatous component. The patient was a 64-year-old smoker male, who presented for the first time with dysuria and hematuria. A bladder tumor invading the anterior and right lateral bladder walls was discovered, without any secondary localizations. Tumor biopsy showed an LCNC with adenocarcinomatous components. The patient was treated by recurrent tumor resections, chemotherapy, and radiotherapy. No improvement was noted despite close follow-up and adequate treatment. Neuroendocrine bladder tumor is known to have an aggressive, rapid, and disadvantageous evolution. Multiple case reports were published so far, and a recent review was conducted in March 2020 by Sanguedolce et al. (2020). More cases are needed to establish the best management plan for this type of tumor.