Bladder
Urothelial nonneoplastic lesions
WHO / ISUP classification (2004)

Author: Monika Roychowdhury, M.D. (see Authors page)

Revised: 5 August 2016, last major update June 2016

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

Cite this page: WHO / ISUP classification (2004). PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/bladderwhoisup.html. Accessed December 6th, 2016.
Definition / General
Classification
    Ash (1940):
  • Classified as transitional cell carcinoma grades 1-4
  • Grade 1 comparable to papilloma
  • Grade 2 comparable to low grade
  • Grade 3 (most) and grade 4 comparable to high grade

    Mostofi (1960):
  • Grade 1 called papilloma and not carcinoma


    WHO / ISUP classification of urothelial lesions (1998)
    Note: each entity is described as a separate topic in the Bladder chapter

    Normal:
  • Flat mucosa with no overt thickness
  • Includes slight disorganization of cells and nuclear pleomorphism, formerly termed mild dysplasia; size of normal urothelial cells is 3x lymphocytes

  • Hyperplasia:
  • Flat hyperplasia, papillary hyperplasia

  • Flat lesions with atypia:
  • Reactive (inflammatory) atypia, atypia of unknown significance, dysplasia (LG IUN), CIS (HG IUN)

  • Papillary urothelial neoplasms:
  • Papilloma, inverted papilloma, papillary neoplasm of low malignant potential, noninvasive papillary carcinoma-low grade, noninvasive papillary carcinoma-high grade

  • Invasive urothelial neoplasms:
  • Lamina propria invasion, muscularis propria (detrusor muscle) invasion

  • Low grade neoplasms:
  • Includes papilloma, inverted papilloma, papillary neoplasm of low malignant potential, low grade papillary urothelial neoplasms, urothelial carcinoma grade 1 of 3, some urothelial carcinomas grade 2 of 3


    • WHO / ISUP classification of tumors of urinary tract (2004)

      Urothelial tumors:
      Infiltrating urothelial carcinoma 8120/3
    • with squamous differentiation
    • with glandular differentiation
    • with trophoblastic differentiation
    • Nested
    • Microcystic
    • Micropapillary 8131/3
    • Lymphoepithelioma-like 8082/3
    • Lymphoma-like
    • Plasmacytoid
    • Sarcomatoid 8122/3
    • Giant cell 8031/3
    • Undifferentiated 8020/3

    • Non-invasive urothelial neoplasias:
    • Urothelial carcinoma in situ 8120/2
    • Non-invasive papillary urothelial carcinoma, high grade 8130/2 or 3
    • Non-invasive papillary urothelial carcinoma, low grade 8130/2 or 1
    • Non-invasive papillary urothelial neoplasm of low malignant potential 8130/1
    • Urothelial papilloma 8120/0
    • Inverted urothelial papilloma 8121/0

    • Squamous neoplasms:
    • Squamous cell carcinoma 8070/3
    • Verrucous carcinoma 8051/3
    • Squamous cell papilloma 8052/0

    • Glandular neoplasms:
    • Adenocarcinoma 8140/3
      • Enteric
      • Mucinous 8480/3
      • Signet-ring cell 8490/3
      • Clear cell 8310/3
    • Villous adenoma 8261/0

    • Neuroendocrine tumours:
    • Small cell carcinoma 8041/3
    • Carcinoid 8240/3
    • Paraganglioma 8680/1

    • Melanocytic tumours:
    • Malignant melanoma 8720/3
    • Nevus

    • Mesenchymal tumours:
    • Rhabdomyosarcoma 8900/3
    • Leiomyosarcoma 8890/3
    • Angiosarcoma 9120/3
    • Osteosarcoma 9180/3
    • Malignant fibrous histiocytoma 8830/3
    • Leiomyoma 8890/0
    • Haemangioma 9120/0
    • Other

    • Haematopoietic and lymphoid tumours:
    • Lymphoma
    • Plasmacytoma 9731/3

    • Miscellaneous tumours:
    • Carcinoma of Skene, Cowper and Littre glands
    • Metastatic tumours and tumours extending from other organs


    • Note: Four digit numbers are the morphology code from ICD-0 and SNOMED Behavior is coded as 0-benign, 1-borderline / uncertain, 2-in situ carcinoma / grade III intraepithelial neoplasia or 3-malignant