Home Education AUAUniversity Education Products & Resources Pathology for Urologists Urinary Bladder Non-Neoplastic Lesions Von Brunn's Nests

Von Brunn's Nests

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  • Reactive proliferation, considered a variation of normal urothelium.
  • May be identified in 85-95% of bladders, most often in the region of trigone.
  • Usually an incidental microscopic finding, but when large or proliferation is florid may be cystoscopically visible as small mucosal blebs.
  • Histology:
    • Solid nests of benign urothelial cells often with regular contour (image A) & (image B).
    • Situated at superficial lamina propria, which may or may not have an obvious connection with overlying urothelium.

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  • May be associated with other proliferative processes such as cystitis cystica and cystitis glandularis.
  • Urothelial CIS from surface urothelium may extend into von Brunn's nests, and should not be mistaken as invasive carcinoma nests.