Primary Small Cell Neuroendocrine Tumor Within a Urethral Diverticulum

Abstract

BACKGROUND: Primary small cell neuroendocrine carcinoma of the urinary tract is a very rare cancer, accounting for fewer than 0.5% of urinary tract tumors. These are aggressive neoplasms with high rates of metastases. Urethral diverticula can be found in up to 6% of women. CASE:A 31-year-old woman presented with a clear vaginal discharge and an anterior vaginal wall mass that was thought to be a recurrent cyst. After surgical dissection, she was noted to have a urethral diverticulum with a solid nodule at the base. Final pathology showed a high-grade small cell neuroendocrine carcinoma.CONCLUSION: Malignancy in a urethral diverticulum can occur in young patients. Clinicians should be aware of this possibility when choosing to manage urethral lesions expectantly.

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

“…4). Among previously reported nine cases of urethral neuroendocrine tumors, these cases had the history of bladder cancer 4–12 . Thus, the pathogenesis of neuroendocrine urethral tumor might be associated with the history of bladder cancer.…”

“…3 There have been only nine reported cases of urethral neuroendocrine tumors, which are extremely rare. [4][5][6][7][8][9][10][11][12] The origin of neuroendocrine tumors arising in the urinary tract is not clear. 13 Urothelial carcinoma may differentiate as a neuroendocrine tumor because it has been reported that cancerous transformation of multipotent epithelial cells in transitional epithelial cells may become a neuroendocrine tumor and that transitional epithelial cells themselves may have neuroendocrine differentiation potential.…”

“…The reported incidence of neuroendocrine tumors in the urinary tract is <0.7% of all bladder tumors 3 . There have been only nine reported cases of urethral neuroendocrine tumors, which are extremely rare 4–12 . The origin of neuroendocrine tumors arising in the urinary tract is not clear 13 …”

“… 3 There have been only nine reported cases of urethral neuroendocrine tumors, which are extremely rare. 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 The origin of neuroendocrine tumors arising in the urinary tract is not clear. 13 …”

Epidemiology of Unconventional Histological Subtypes of Urethral Cancer

“…Most common urethral-cancer histological subtypes are urothelial, squamous-cell carcinoma (SCC), and adenocarcinoma [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. Since urethral cancer has been studied in very small patient groups, only more historical studies as well as case reports have focused on other unconventional histological subtypes, instead of urothelial, SCC, and adenocarcinoma of the urethra [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. To the best of our knowledge, no previous investigation compared different unconventional urethral-cancer histologies.…”