Primary Neuroendocrine Tumors of the Ureter: A Short Review

Abstract

Neuroendocrine tumors represent 0.05% of urinary tract malignancies, and most originate in the bladder. Their pathogenesis is debated, since ureters are thought to lack neuroendocrine cells. Morphologically, most ureteral neuroendocrine tumors demonstrate the typical small cell neuroendocrine appearance, are immunohistochemically positive for synaptophysin/chromogranin A/CD56, and show electron-dense granules by electron microscopy. Clinical presentation is similar to that of other more common ureteral neoplasms. Prognosis is usually dismal, but a multimodal treatment approach including platinum-based adjuvant or neoadjuvant chemotherapy seems to be beneficial.

Neuroendocrine Tumor of the Ureter: A Zebra Among Horses

“…8 Most primary neuroendocrine tumors of the ureter occur in the sixth to seventh decade of life, and there does not appear to be a gender predilection. 3,4 Our patient thus demonstrated the classically reported clinical features; however, the age was premature. Although the symptoms that our patient presented with may be classic in patients with neuroendocrine tumors of the upper urinary tract, benign diseases by far are a more common cause of such symptomatology.…”

“…Overall, pain and hematuria are the most common initial symptoms. 3,4 However, unlike urothelial carcinomas, locally advanced or nodal disease at presentation is common, with an estimated 20%–45% of patients harboring advanced disease at the time of diagnosis 5,6 —these findings are in line with the aggressive behavior demonstrated by neuroendocrine tumors arising from other sites. 7 …”

“…Primary neuroendocrine tumors of the urinary system are uncommon, accounting for less than 0.05% of all urinary tract malignancies. 2,3 Primary ureteral neuroendocrine tumors are furthermore rare, with less than 30 cases having been reported since the initial description of these tumors in the mid-1980s. 3 Herein, we report a case of small cell carcinoma of the ureter and discuss the clinical presentation, etiology, prognosis, and management of these uncommon tumors.…”

Incidental finding of a small cell neuroendocrine carcinoma of the ureter

“…The urinary tract is a rare site for NETs and has an incidence of only 0.05%. In these cases they are usually found in the bladder, and are mostly aggressive with a potential to invade surrounding tissue and vascular structures 1–3. This makes the ureter an extremely rare site for neuroendocrine carcinomas, hence scarce reporting in the world literature; we estimate there have been less than 30 cases reported to date1–10…”

“…When present in the ureter, they mostly exhibit a typical morphological small cell neuroendocrine appearance1 2 but can also have a large cell appearance although this appears to be even rarer 8. The prognosis of ureteric NET is very poor although a multimodal treatment approach, including surgery, radiotherapy, platinum-based adjuvant or neoadjuvant chemotherapy, has been used, which may offer some respite and prevent extensive metastasis 1 5 6 10. Where a patient is unfit for aggressive treatment, watchful waiting is always an option.…”