Kidney tumor - Adult malignancies
Renal pelvic tumors
Small cell neuroendocrine carcinoma

Author: Nicole K. Andeen, M.D. (see Authors page)
Editor: Maria Tretiakova, M.D.

Revised: 3 February 2017, last major update July 2015

Copyright: (c) 2003-2017, PathologyOutlines.com, Inc.

PubMed Search: Small cell neuroendocrine carcinoma [title] kidney

Cite this page: Small cell neuroendocrine carcinoma. PathologyOutlines.com website. http://pathologyoutlines.com/topic/kidneytumormalignantsmallcell.html. Accessed May 29th, 2017.
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
Pathophysiology
  • Likely arises from a multipotent stem cell
Clinical features
Radiology description
Case reports
Treatment
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

Images hosted on PathOut server:

Large invasive tumor


Images hosted on other servers:

Urothelial small cell

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

Images hosted on other servers:

Mixed with urothelial carcinoma

Small cell neuroendocrine tumor

Various images

Minimal cytoplasm,
nuclear molding,
indistinct nucleoli


Absence of nucleoli and high mitotic activity

CD56, synaptophysin, TTF1

Synaptophysin+

Negative stains
Electron microscopy description
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)
Additional references