Thursday, October 2, 2008


Breast Cancer Stages

A cancer's stage refers to how much the cancer has grown and where it has spread. Tumors can be noninvasive or invasive. 2

  • Noninvasive breast cancer, or carcinoma in situ, is a tumor that has not spread beyond the ducts or the lobules, depending on where it started. 2
  • Ductal carcinoma in situ (DCIS) is cancer that is confined to the ducts.
  • Lobular carcinoma in situ (LCIS) is a condition that is confined to the lobules or milk-making glands. Although not considered a true cancer, having LCIS increases the risk of getting cancer later
  • An invasive tumor has spread beyond where it began, and there are three different stages of invasiveness 2:
    • Localized stage: The tumor is still only within the breast
    • Regional stage: The tumor has spread to the tissue surrounding the breast or there are cancer cells within nearby lymph nodes. Lymph nodes are small masses of tissues found throughout the body that are involved in fighting infection. The more lymph nodes with cancer, the more serious the cancer may be 1,2
    • Distant (advanced/metastatic) stage: The tumor has spread away from the breast to other tissues in the body (eg, lung, liver, bone, or brain)
Breast Cancer Stages - early, spread, metastatic

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TNM staging system

Staging systems help describe the cancer, so that the doctor can decide what treatments are appropriate such as whether the tumor is operable (meaning that surgery should be done to remove the tumor). The TNM (Tumor, Nodal, Metastasis) Staging System is the most common method of staging breast cancer. According to the TNM system, breast cancer is grouped into five stages from 0 to IV based on how large the tumor is, the tumor's nodal status (whether or not cancer cells have spread to the lymph nodes), and whether the tumor has spread (metastasis). 3

The terms "early" and "advanced" are sometimes used to describe tumors, but these terms may be used differently by different doctors. Generally, "early" or "early-stage" breast cancer means that the cancer has not spread beyond the breast or lymph nodes under the arm (known as auxiliary lymph nodes).Stage 0,I,and II, as well as some stage III cancers, are usually considered early-stage. Ask your doctor or nurse for more information about the stage of your tumor. Here are brief descriptions of each stage of breast cancer, according to the TNM system. 4,5

Stages 0-IV 3,4

Stage 0 is very early breast cancer. The cancer cells are still only in the duct or lobule where they began.

Stage I Means that the tumor is small, 0 to 2 cm (about 1 inch) wide, with negative lymph nodes (no cancer cells in the lymph nodes). The tumor has not spread outside of the breast.

Stage II means one of the following:

  • The tumor is 2 to 5 cm (about 1 to 2 inches) wide, and lymph nodes under the arm on the same side of the body as the tumor may be positive (meaning that the lymph nodes have cancer cells in them) or
  • The tumor is more than 5 cm (about 2 inches) wide, but the lymph nodes are still negative

Stage III, sometimes known as locally advanced cancer, means one of the following:

  • The tumor has grown larger than 5 cm wide, and cancer has spread to lymph nodes under the arm or
  • The tumor is any size, but more lymph nodes are now positive. These nodes may be under the arm and attached to one another or in the surrounding tissue and enlarged or
  • The tumor is any size and has spread to the chest wall or the skin or
  • The tumor is any size and there are positive lymph nodes in the chest above or just below the collar bone

Stage IV means that the breast cancer is metastatic: the cancer has spread to somewhere else in the body.


  • 1. Altman R, Sarg MJ. The Cancer Dictionary-Revised Edition. New York, NY: Checkmark Books; 2000.
  • 2. American Cancer Society. Breast Cancer Facts & Figures 2005-2006. Atlanta, Ga: American Cancer Society, Inc; 2005.
  • 3. American Cancer Society (ACS)/National Comprehensive Cancer Network (NCCN). Breast Cancer: Treatment Guidelines for Patients. Version VIII/September 2006. ACS/NCCN; 2006.
  • 4. Breast Website. Stages of breast cancer. Available at: Accessed September 2, 2008.
  • 5. National Cancer Institute/US National Institutes of Health Website. Dictionary of cancer terms. Available at: Accessed September 2, 2008.