Bladder, ureter & renal pelvis
Neuroendocrine neoplasms
Small cell neuroendocrine carcinoma
Last author update: 1 July 2015
Last staff update: 11 August 2023 (update in progress)
Copyright: 2003-2023, PathologyOutlines.com, Inc.
PubMed Search: Small cell neuroendocrine carcinoma [title] kidney
Table of Contents
Definition / general | Epidemiology | Pathophysiology | Clinical features | Radiology description | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology images | Positive stains | Negative stains | Electron microscopy description | Molecular / cytogenetics description | Differential diagnosis | Additional referencesCite this page: Andeen NK, Tretiakova M. Small cell neuroendocrine carcinoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/kidneytumormalignantsmallcell.html. Accessed November 29th, 2023.
Definition / general
- High grade neuroendocrine neoplasm resembling small cell carcinoma of other organs
- Pure or admixed with high grade urothelial carcinoma of the kidney
- Rare, < 1% of renal neoplasms, ~ 50 cases reported
- Very rarely has been reported with renal cell carcinoma (J Urol 1998;159:1624, Gerontologist 1991;31:631)
Epidemiology
- Median age 59 - 65 years, may be seen with high grade urothelial carcinoma of the kidney (Hum Pathol 2011;42:1792, Clin Genitourin Cancer 2014;12:422)
Pathophysiology
- Likely arises from a multipotent stem cell
Clinical features
- Presentation: hematuria, back pain or abdominal pain (Clin Genitourin Cancer 2014;12:422, Hum Pathol 2011;42:1792)
- Highly aggressive behavior, often local or distant metastases (Cancer 2003;97:1436, Clin Genitourin Cancer 2014;12:422)
- Median survival 8 - 20 months (Cancer 2003;97:1436, Clin Genitourin Cancer 2014;12:422)
Radiology description
- Medullary location, lack of central necrosis in a large tumor (Magn Reson Imaging 2005;23:515)
Case reports
- 55 year old man with multicentric small cell neuroendocrine neoplasm of the renal pelvis and ureter (Indian J Urol 2008;24:571)
- 59 year old woman with primary small cell carcinoma of kidney after renal transplantation (Chin J Cancer Res 2013;25:608)
- 71 year old woman with combined small cell and transitional cell carcinoma of the renal pelvis (Arch Pathol Lab Med 1993;117:239)
- 76 year old woman with small cell carcinoma of the kidney (Arch Pathol Lab Med 2001;125:796)
- Primary oat cell carcinoma of the kidney (Am J Surg Pathol 1984;8:855)
Treatment
- Surgery
- Chemotherapy (platinum based, may receive same as pulmonary small cell carcinoma) +/- radiation (Cancer 2003;97:1436)
- Slightly improved survival of 17.3 months with neoadjuvant chemotherapy prior to nephrectomy (Clin Genitourin Cancer 2014;12:422)
Gross description
- Unifocal, centered in renal pelvis, usually invading perinephric adipose tissue (Hum Pathol 2011;42:1792)
- Median size 11 cm, mean 7.1 cm in another study (range from 2.3 to 23 cm)
Gross images
Contributed by Nicole K. Andeen, M.D. and AFIP images
Urothelial small cell
Large invasive tumor
Images hosted on other servers:
In renal pelvis
Microscopic (histologic) description
- Similar morphology to small cell carcinoma of the lung
- Diffuse growth of small cells with minimal cytoplasm, nuclear molding, indistinct nucleoli, high mitotic activity and apoptosis, lymphovascular invasion, necrosis
Microscopic (histologic) images
Contributed by Nicole K. Andeen, M.D.
Mixed with urothelial carcinoma
Minimal cytoplasm,
nuclear molding,
indistinct
nucleoli
Synaptophysin+
Images hosted on other servers:
Small cell neuroendocrine tumor
Absence of nucleoli and high mitotic activity
CD56, synaptophysin, TTF1
Synaptophysin+
Cytology images
Contributed by Bonnie Choy, M.D.
Small cell carcinoma
Positive stains
Negative stains
Electron microscopy description
- Scanty electron dense neurosecretory granules and desmosomes supporting epithelial differentiation (Cancer 1987;60:1809, Pol J Pathol 2014;65:15)
Molecular / cytogenetics description
- In urinary bladder, studies of coexistent urothelial carcinoma and small cell carcinoma show very similar loss of heterozygosity and X-inactivation patterns, suggesting that urothelial and small cell components derive from same cells in the urothelium, rather than transformation from a population of normal neuroendocrine cells (Am J Pathol 2005;166:1533)
Differential diagnosis
- Lymphoma: use immunostains to differentiate
- Metastatic small cell lung cancer: radiology, clinical history of primary lung tumor, absence of high grade urothelial component
- TTF1 is unlikely to have discriminatory value (Appl Immunohistochem Mol Morphol 2012;20:429, Clin Genitourin Cancer 2014;12:422, Zhonghua Bing Li Xue Za Zhi 2012;41:538)
- Other small blue cell tumors: PNET / Ewing's sarcoma, neuroblastoma, rhabdomyosarcoma, desmoplastic small round cell tumor
- Poorly differentiated urothelial carcinoma, plasmacytoid carcinoma, lymphoepithelioma-like carcinoma, metastatic Merkel cell carcinoma, synovial sarcoma
Additional references
