Current Urology Reports

, 20:80 | Cite as

Variant Histology in Bladder Cancer—Current Understanding of Pathologic Subtypes

  • Manju AronEmail author
Urothelial Cancer (S Daneshmand, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Urothelial Cancer


Purpose of Review

Urothelial carcinomas (UC) are characterized by variant morphologies. However, the diagnosis of these variants can be challenging, in part due to their evolving diagnostic criteria. This review discusses the diagnostic criteria, molecular features, and prognostic implications of the UC variants. Evolving subtypes of UC are also briefly discussed.

Recent Findings

The WHO 2016 classification of tumors of the urinary system has refined the morphologic criteria for the diagnosis of UC variants. Many of these follow a more aggressive clinical course, but conclusive data on their effect on survival are lacking. The molecular alterations characteristic of some of these variants may be amenable to targeted therapies.


Accurate identification of variant histology in UC has important implications for patient management. Despite identification of distinct molecular alterations in some of these variants, current molecular classifiers of invasive UC have not been significantly analyzed in these subtypes, opening up areas of future research.


Bladder carcinoma Urothelial carcinoma variants Variant histology Divergent differentiation 


Compliance with Ethical Standards

Conflict of Interest

Manju Aron declares no potential conflicts of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.University of Southern CaliforniaLos AngelesUSA

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