Skip to main content

Breast Cancer

Treatment of Breast Cancer by Stage

On this page

This information is based on AJCC Staging systems prior to 2018 which were primarily based on tumor size and lymph node status. Since the updated staging system for breast cancer now also includes estrogen receptor (ER), progesterone receptor (PR), and HER2 status, the stages may be higher or lower than previous staging systems. Whether or not treatment strategies will change with this new staging system are yet to be determined. You should discuss your stage and treatment options with your doctor. 

The stage of your breast cancer is an important factor in making decisions about your treatment options. In general, the more the breast cancer has spread, the more treatment you will likely need. But other factors can also be important, such as:

  • If the cancer cells have hormone receptors (that is, if the cancer is ER-positive or PR-positive)
  • If the cancer cells have large amounts of the HER2 protein (that is, if the cancer is HER2-positive)
  • If the cancer cells have a certain gene mutation (change)
  • Your overall health and personal preferences
  • If you have gone through menopause or not
  • How fast the cancer is growing (measured by grade or other measures) and if it is affecting major organs like the lungs or liver

Talk with your doctor about how these factors can affect your treatment options.

Stage 0

Stage 0 cancers are limited to the inside of the milk duct and are non-invasive (does not invade nearby tissues). 

Ductal carcinoma in situ (DCIS) is a stage 0 breast tumor.

Lobular carcinoma in situ (LCIS) used to be categorized as stage 0, but this has been changed because it is not cancer. Still, it does indicate a higher risk of breast cancer. See Lobular Carcinoma in Situ (LCIS) for more information.

Stages I-III

Treatment for stages I to III breast cancer usually includes surgery and radiation therapy, often with chemo or other drug therapies either before (neoadjuvant) or after (adjuvant) surgery.

Stage I: These breast cancers are still relatively small and either have not spread to the lymph nodes or have only a tiny area of cancer spread in the sentinel lymph node (the first lymph node to which cancer is likely to spread).

Stage II: These breast cancers are larger than stage I cancers and/or have spread to a few nearby lymph nodes.

Stage III: These tumors are larger or are growing into nearby tissues (the skin over the breast or the muscle underneath), or they have spread to many nearby lymph nodes.

Stage IV (metastatic breast cancer)

Stage IV cancers have spread beyond the breast and nearby lymph nodes to other parts of the body. 

Recurrent breast cancer

Cancer is called recurrent when it comes back after primary treatment. Recurrence can be local (in the same breast or in the surgery scar), regional (in nearby lymph nodes), or in a distant area. Treatment for recurrent breast cancer  depends on where the cancer comes back and what treatments you’ve had before.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Henry NL, Shah PD, Haider I, Freer PE, Jagsi R, Sabel MS. Chapter 88: Cancer of the Breast. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff’s Clinical Oncology. 6th ed. Philadelphia, Pa: Elsevier; 2020.

Jagsi R, King TA, Lehman C, Morrow M, Harris JR, Burstein HJ. Chapter 79: Malignant Tumors of the Breast. In: DeVita VT, Lawrence TS, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 11th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2019.

National Cancer Institute. Physician Data Query (PDQ). Breast Cancer Treatment – Health Professional Version. 2021. Accessed at https://www.cancer.gov/types/breast/hp/breast-treatment-pdq on August 17, 2021.

National Comprehensive Cancer Network (NCCN). Practice Guidelines in Oncology: Breast Cancer. Version 6.2021. Accessed at https://www.nccn.org/professionals/physician_gls/pdf/breast.pdf on August 17, 2021.

Last Revised: September 18, 2019

American Cancer Society Emails

Sign up to stay up-to-date with news, valuable information, and ways to get involved with the American Cancer Society.