Ureters
General
Nephrogenic metaplasia / adenoma

Author: Sean Williamson, M.D. (see Authors page)

Revised: 6 September 2017, last major update July 2012

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Ureters nephrogenic metaplasia / adenoma

Cite this page: Williamson, S. Nephrogenic metaplasia / adenoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/uretersnephrometaureter.html. Accessed September 24th, 2017.
Definition / general
  • Rare, associated with stone or other irritation of the mucosa
  • Nephrogenic adenoma: similar histologic findings but presenting as a mass
  • For nephrogenic adenoma, mean age 52 years, range 15 to 94 years (entire urinary tract), M/F = 2:1; ureter is rare site (4% of all urinary tract tumors, Mod Pathol 1995;8:722)
Microscopic (histologic) description
  • Proliferation of tiny mucin containing microcysts, medium sized tubular structures (resembling renal tubules) and small exophytic papillary structures
  • Lined by cuboidal cells similar to renal tubular epithelial cells
  • Basement membrane around tubules may be appreciable but not prominent
  • Tubules / cysts often have eosinophilic or basophilic secretion
  • Generally mild cytologic atypia, characterized by enlarged vesicular nuclei and prominent nucleoli
  • No mitotic figures
  • May have transmural involvement and appear infiltrative, (Mod Pathol 2002;15:765, Am J Clin Pathol 1983;80:92)
Microscopic (histologic) images

Images hosted on other servers:

Cross section of ureter

Tiny microcystic structures
superficially resembling signet ring cells
and larger tubular structures in the
lamina propria of the ureter

Higher magnification of
microcysts surrounded by
a thickened basement membrane

Small elongated tubular
structures lying in
a fibrous stroma

A cystically dilated
tubule contains mucin
and is lined by
hobnail cells

Cytokeratin

Positive stains
Negative stains
Electron microscopy description
  • Epithelial cells with sparse microvilli and thick basal lamina
Molecular / cytogenetics description
  • In renal transplant patients with opposite sex donor, FISH reveals the donor’s sex chromosomes within the lesion, suggesting implantation and proliferation of shed renal tubular cells into injured mucosa (N Engl J Med 2002;29:347)
Molecular / cytogenetics images

Images hosted on other servers:

FISH and H&E in transplant patients