Mixed Adenocarcinomatous and Neuroendocrine Tumor of the Urinary Bladder With Concomitant Carcinoma In Situ: A Case Report With a Comprehensive Immunohistochemical Analysis and Review of the Literature

Neuroendocrine tumour of the urinary bladder

We report a rare case of urinary bladder neuroendocrine tumour (NET) in a young, non-smoking man. He had no known risk factors and no comorbidities. After being diagnosed with a bladder tumour while being investigated for flank pain and poor renal function, he was treated with transurethral resection of the bladder tumour and deroofing of ureters bilaterally. Characteristic histological features were identified for NETs. After a thorough staging workup by CT of the thorax, abdomen and pelvis, MRI of the liver and DOTATATE positron emission tomography-CT, no other lesion or metastasis was identified.Primary NETs in the genitourinary tract are rare, comprising approximately 1-2% of genitourinary malignancies. Timely staging and histological diagnosis are the keystones of initial management. Awareness of potential diagnostic pitfalls is essential to ensure the accurate and timely diagnosis of vesical NETs, given their significant impact on management strategies and patient prognosis.

Ureter mixed neuroendocrine-non-neuroendocrine neoplasm: a case report and literature review

Cases of mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) of the urinary system are rare, and reports of primary MiNENs in the ureter are lacking. Herein, we present the case of a 71-year-old man who presented with painless gross hematuria and weight loss. Contrast-enhanced abdominal computed tomography (CT) revealed a tumor, comprising small cell neuroendocrine carcinoma (SCNEC) and adenocarcinomatous components, attached to the ureter. The SCNEC components were strongly positive for synaptophysin, CD56 and INSM1 and adenocarcinomatous components were strongly positive for CDX2 and cytokeratin 20, respectively. Four weeks post-surgery, the patient received four cycles of cisplatin-based chemotherapy; the 7-month follow-up CT confirmed that he was healthy without disease recurrence. The occurrence of MiNEN in the ureter with SCNEC and adenocarcinomatous components is extremely rare, wherein histopathological and immunohistochemical features aid in the diagnosis MiNEN. With its aggressive nature, MiNEN can only be effectively treated by early diagnosis and radical surgery.

A systematic review and meta-analysis of radical cystectomy in the treatment of muscular invasive bladder cancer (MIBC)

Background

A meta-analysis was conducted to evaluate the curative effect of radical cystectomy in the treatment of muscular invasive bladder cancer (MIBC).

Methods

Chinese and English databases were searched using free combinations of the terms “bladder cancer,” “radical cystectomy,” “muscle invasive bladder cancer,” and “bladder preservation.” Review Manager 5.3 software was used for the meta-analysis.

Results

A total of 12 articles were included in the meta-analysis, most of which had low-bias risk and were of medium and high quality. A funnel chart showed that the circles of some studies were basically symmetrical with the midline, suggesting that the research accuracy was high, the publications were not biased, and the final conclusions were credible. Twelve articles analyzed patients’ 5-year survival rate in randomized controlled trials (RCTs). In these RCTs, the experimental group (expt group) comprised 775 cases and the control group (ctrl group) comprised 766 cases. A heterogeneity test using the fixed-effects model (FEM) showed Chi² =2.19, df =11, I²=0%, P=1.00>0.1, Z =2.57, odds ratio (OR) =1.30, 95% confidence interval (CI): 1.06–1.59, and P=0.01<0.05. 3 articles analyzed patients’ 10-year survival rates in RCTs. These trials comprised a total of 417 patients (209 in the expt group and 208 in the ctrl group). The overall heterogeneity test showed Chi² =0.40, df =2, I²=0%, P=0.82>0.1, Z =1.42, OR =1.32, 95% CI: 0.90–1.94, and P=0.16>0.05. 6 articles analyzed 5-year distant metastasis rates (DMRs) in RCTs. The overall heterogeneity test showed Chi² =1.68, df =5, I²=0%, P=0.89>0.1, Z =1.70, OR =1.28, 95% CI: 0.96–1.71, and P=0.09>0.05).

Discussion

Our meta-analysis confirmed that radical cystectomy is effective in the treatment of MIBC and is worthy of clinical promotion.