Main content

    HealthWise KnowledgeBase

    Stages of Colorectal Cancer

    Stages of Colorectal Cancer



    Topic Overview

    The type of treatment you will receive for your Reference colorectal cancer Opens New Window depends on what stage it is in. Staging is a process doctors use to describe how far the cancer has spread.

    Although there are several methods of staging, most doctors now use the TNM method. The TNM method is based on the size of the tumor (T), the spread of the cancer into nearby lymph nodes (N), and the spread of the cancer to other body parts (M, for metastasis). Some doctors still use an older method of staging called Dukes.

    TNM staging labels
    T (describes tumor size and how deeply it has penetrated the tissue layers of the colon or rectum) N (describes how far the cancer has spread to nearby lymph nodes) M (describes whether the cancer has spread to other parts of the body—metastasized)
    • TX: The tumor cannot be assessed.
    • T0: There is no evidence of a tumor.
    • Tis: The tumor is "in situ," meaning it was caught very early and has not grown beyond the lining of the colon or rectum.
    • T1: The tumor has grown through the lining and into the connective tissue.
    • T2: The cancer has grown into the thick inner muscle.
    • T3: The cancer has grown completely through the thick inner muscle. It has spread to the outer lining but not to any nearby organs or tissues.
    • T4a: The cancer has spread completely through the wall of the colon or rectum and to the surface of nearby organs.
    • T4b: The cancer has spread completely through the wall of the colon or rectum and into nearby tissues or organs.
    • N0: Cancer has not spread to lymph nodes.
    • N1: Cancer cells are found in 1 to 3 regional lymph nodes.
    • N1a: Cancer cells are found in 1 regional lymph node.
    • N1b: Cancer cells are found in 2–3 regional lymph nodes.
    • N1c: Tumor deposits in the nearby tissues without the cells spreading to the regional nodes.
    • N2: Cancer cells are found in 4 or more regional lymph nodes.
    • N2a: Cancer cells are found in 4–6 regional lymph nodes.
    • N2b: Cancer cells are found in 7 or more regional lymph nodes.
    • M0: Cancer cells have not spread to other parts of the body.
    • M1: Cancer cells have spread to other parts of the body.
    • M1a: Cancer cells have spread to one organ or site, such as the liver, lung, ovary, or non-regional node.
    • M1b: Cancer cells have spread to more than one organ or site in the peritoneum.

    Let's say your doctor has told you your cancer is at stage II. In the table below, find the column labeled "Stage." Now go down to the row labeled "II." In the columns to the right are the TNM staging system. You can find a description of each TNM label in the table above.

    The Dukes staging system is shown in the far right column. This lists the stages as A, B, C, and D. The Dukes stages A through D are the same as TNM stages I through IIIC.

    How colorectal cancer is staged
    Stage T N M Dukes

    0

    Tis

    N0

    M0

    –

    I

    T1

    T2

    N0

    N0

    M0

    M0

    A

    A

    IIA

    T3

    N0

    M0

    B

    IIB

    T4a

    N0

    M0

    B

    IIC

    T4b

    N0

    M0

    B

    IIIA

    T1–T2

    T1

    N1/N1c

    N2a

    M0

    M0

    C

    C

    IIIB

    T3–T4a

    T2–T3

    T1–T2

    N1/N1c

    N2a

    N2b

    M0

    M0

    M0

    C

    C

    C

    IIIC

    T4a

    T3–T4a

    T4b

    N2a

    N2b

    N1–N2

    M0

    M0

    M0

    C

    C

    C

    IVA

    Any T

    Any N

    M1a

    –

    IVB

    Any T

    Any N

    M1b

    –



    By: Reference Healthwise Staff Last Revised: Reference August 27, 2012
    Medical Review: Reference E. Gregory Thompson, MD - Internal Medicine
    Reference Kenneth Bark, MD - Surgery, Colon and Rectal


    This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.


    Topic Contents