Primary neuroendocrine carcinoma of the urethra

A case of neuroendocrine tumor at the external urethral meatus after total cystectomy

Introduction

The histological types of urethral cancer are mainly squamous cell or transitional cell carcinoma. Neuroendocrine tumor is extremely a rare type of urethral cancer.

Case presentation

A 72-year-old man visited with an erythema at the external urethral meatus. After 3 months, a 1-cm reddish solid tumor was found on the external urethral meatus. He had a history of bladder cancer (pTa with carcinoma in situ), including the prostatic urethra, and underwent radical cystectomy with urethrectomy and ileal conduit construction 11 years ago. After 3 months, a 1-cm reddish solid tumor was found on the external urethral meatus. The pathological diagnosis was a neuroendocrine tumor. Partial penectomy was performed.

Conclusion

Small cell neuroendocrine tumor could occur on urethral remnant after radical cystectomy with urethrectomy for urothelial cancer. Inspection of the penis and urethral meatus is important during regular follow-up of patients after radical cystectomy.

Small cell carcinoma arising from the bulbar urethra: a case report and literature review

Primary neuroendocrine carcinomas of the genitourinary tract are rare and aggressive tumors carrying a bad prognosis. With squamous cell and transitional cell carcinoma being the most commonly reported urethral malignancies, primary small cell carcinoma (SCC) of the urethra is extremely rare. To date, only 5 cases have been reported in the literature. We present the first case of primary SCC occurring in the bulbar urethra in an 89-year-old male. We discuss the clinical, histological and immunohistochemical features of SCC of the urethra. Furthermore, we summarize the available literature and discuss the possible treatment options for this rare yet aggressive neoplasm.

Small cell carcinoma arising from the proximal urethra

Primary neuroendocrine carcinomas of the lower urinary tract are distinctly rare, locally aggressive neoplasms with a high rate of metastasis. We present a case of primary small cell carcinoma of the urethra occurring in a 64-year-old man. The clinical, histological and immunohistochemical features of urethral small cell carcinoma are highlighted with respect to the differential diagnosis of neuroendocrine and other urethral tumors. The possible histogenesis of urethral small cell carcinoma, reported at this location in only a small number of cases, is briefly discussed. We favor an origin from pluripotent epithelial stem cells as one of the possible histogenic pathways.