Colon tumor
Carcinoma
WHO classification of colorectal carcinoma

Author: Raul Gonzalez M.D. (see Authors page)

Revised: 31 December 2015, last major update December 2015

Copyright: (c) 2002-2015, PathologyOutlines.com, Inc.

PubMed Search: WHO classification [title] colorectal carcinoma
Cite this page: World Health Organization (WHO) classification of colorectal carcinoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/colontumorwhoclassification.html. Accessed December 7th, 2016.
Definition / General
  • WHO classification of tumors of the colon and rectum
  • Currently on 4th edition, published in 2010
  • Based on histologic appearance, not molecular characteristics
  • Similar classification used in College of American Pathologists protocol for examination of colorectal carcinoma specimens
Classification
  • Epithelial tumors:
    • Premalignant lesions
      • Adenoma
      • Tubular
      • Villous
      • Tubulovillous
      • Dysplasia (intraepithelial neoplasia, low grade)
      • Dysplasia (intraepithelial neoplasia, high grade)
    • Serrated lesions
      • Hyperplastic polyp
      • Sessile serrated adenoma/polyp
      • Traditional serrated adenoma
    • Hamartomas
      • Cowden-associated polyp
      • Juvenile polyp
      • Peutz-Jeghers polyp
    • Carcinomas
      • Adenocarcinoma
        • Cribriform comedo-type adenocarcinoma
        • Medullary carcinoma
        • Micropapillary carcinoma
        • Mucinous adenocarcinoma
        • Serrated adenocarcinoma
        • Signet ring cell carcinoma
      • Adenosquamous carcinoma
      • Spindle cell carcinoma
      • Squamous cell carcinoma
      • Undifferentiated carcinoma
    • Neuroendocrine neoplasms
      • Neuroendocrine tumor (NET)
        • NET G1 (carcinoid)
        • NET G2
      • Neuroendocrine carcinoma (NEC)
        • Large cell NEC
        • Small cell NEC
      • Mixed adenoneuroendocrine carcinoma
      • EC cell, serotonin-producing NET
      • L cell, Glucagon-like peptide-producing, and PP / PYY-producing NETs

  • Mesenchymal tumors:
    • Leiomyoma
    • Lipoma
    • Angiosarcoma
    • Gastrointestinal stromal tumor
    • Kaposi sarcoma
    • Leiomyosarcoma

  • Lymphomas

  • Secondary tumors