Skip to content

Colorectal Cancer Health Center

Font Size

Cellular Classification and Pathology of Rectal Cancer

    The World Health Organization (WHO) classification of tumors of the colon and rectum include the following:[1]

    Epithelial Tumors

    Recommended Related to Colorectal Cancer

    Colorectal Cancer Clinical Trials

    Before doctors can prescribe new medications and treatments, they must be shown to be safe and effective. Colorectal cancer clinical trials allow test the effects of new medications on volunteers with colorectal cancer. The researchers follow a strict protocol and use carefully controlled conditions to evaluate the drugs being developed. The evaluation focuses on how well the drug treats colorectal cancer. Researchers also determine its safety and any possible side effects. Some patients with colorectal...

    Read the Colorectal Cancer Clinical Trials article > >

    Adenoma

    • Tubular.
    • Villous.
    • Tubulovillous.
    • Serrated.

    Intraepithelial neoplasia (dysplasia) associated with chronic inflammatory diseases

    • Low-grade glandular intraepithelial neoplasia.
    • High-grade glandular intraepithelial neoplasia.

    Carcinoma

    • Adenocarcinoma.
    • Mucinous adenocarcinoma.
    • Signet-ring cell carcinoma.
    • Small cell carcinoma.
    • Adenosquamous carcinoma.
    • Medullary carcinoma.
    • Undifferentiated carcinoma.

    Carcinoid (well-differentiated neuroendocrine neoplasm)

    • Enterochromaffin (EC)-cell, serotonin-producing neoplasm.
    • L-cell, glucagon-like peptide and pancreatic polypeptide/peptide YY (PYY)-producing tumor.
    • Others.

    Mixed carcinoma-adenocarcinoma

    • Others.

    Nonepithelial Tumors

    • Lipoma.
    • Leiomyoma.
    • Gastrointestinal stromal tumor.
    • Leiomyosarcoma.
    • Angiosarcoma.
    • Kaposi sarcoma.
    • Melanoma.
    • Others.

    Malignant lymphomas

    Adenocarcinomas account for the vast majority of rectal cancers. Other histologic types of colorectal cancer account for an estimated 2% to 5% of colorectal tumors.[2]

    References:

    1. Hamilton SR, Aaltonen LA: Pathology and Genetics of Tumours of the Digestive System. Lyon, France: International Agency for Research on Cancer, 2000.
    2. Kang H, O'Connell JB, Leonardi MJ, et al.: Rare tumors of the colon and rectum: a national review. Int J Colorectal Dis 22 (2): 183-9, 2007.

      This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http:// cancer .gov or call 1-800-4-CANCER.

      WebMD Public Information from the National Cancer Institute

      Last Updated: February 25, 2014
      This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
      1

      Today on WebMD

      Colorectal cancer cells
      The right diagnosis is the most important factor.
      man with a doctor
      Our health check will steer you in the right direction.
       
      sauteed cherry tomatoes
      Fight cancer one plate at a time.
      bladder cancer x-ray
      Do you know the warning signs?
       
      bread
      ARTICLE
      Colon vs Rectal Cancer
      VIDEO
       
      New Colorectal Treatments
      VIDEO
      can lack of sleep affect your immune system
      FEATURE
       
      Cancer Facts Quiz
      QUIZ
      Virtual Colonoscopy
      VIDEO
       
      Picture of the Colon
      ANATOMY
      Vitamin D
      SLIDESHOW
       

      WebMD Special Sections