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Treatment of Breast Cancer by Stage
The stage of your breast cancer is one of the most important factors in making decisions about your treatment options. In general, the more your breast cancer has spread, the more treatment you will likely need.
Other factors that can affect your treatment options include:
- Whether the cancer cells have hormone receptors (ER-positive or PR-positive)
- Whether the cancer cells have large amounts of the HER2 protein (HER2-positive)
- Whether the cancer cells have certain gene changes (mutations) such as BRCA1, BRCA2, ESR1, PALB2, or PIK3CA
- How fast the cancer is growing and whether it has affected major organs like your lungs or liver
- Whether you have gone through menopause
- Your overall health and personal preferences
Talk with your cancer care team about how these factors affect your treatment options.
This information is based on AJCC staging systems prior to 2018. These systems were primarily based on tumor size and lymph node status. The updated staging system for breast cancer now also includes estrogen receptor (ER), progesterone receptor (PR), and HER2 status. Because of this, the stages may now be higher or lower than previous staging systems.
Treatment strategies are slowly changing with this new staging system, so you should discuss your stage and treatment options with your cancer care team.
Stage 0 (DCIS)
Stage 0 cancers are limited to the inside of the milk ducts. They are non-invasive, meaning the cancer does not invade nearby tissues.
Ductal carcinoma in situ (DCIS) is a stage 0 breast tumor. It is usually treated with breast-conserving surgery (lumpectomy) or mastectomy. This is sometimes followed by radiation therapy, hormone therapy, or both.
Lobular carcinoma in situ (LCIS) used to be categorized as stage 0, but this has changed because it is not considered cancer. However, having LCIS does increase your risk of breast cancer. See Lobular Carcinoma in Situ (LCIS) for more information.
Stages I-III
Treatment for breast cancer stages I, II, and III usually includes surgery and radiation therapy. Chemo or other medicines are often given as well. This is done either before surgery (neoadjuvant) or after surgery (adjuvant).
Stage I: These cancers are still fairly small. They have not spread to the lymph nodes, or they 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 cancers are larger than stage I cancers and/or they have spread to lymph nodes under the armpit on the same side as the cancer.
Stage III: These tumors are larger or they are growing into nearby tissues, such as 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, such as the bones, lungs, liver, or brain.
Treatment can often shrink tumors or slow their growth. It can improve symptoms and help some people live longer. These cancers are considered very difficult to cure, but many people live for years with treatment.
Recurrent breast cancer
Recurrent cancer is cancer that comes back after treatment.
This recurrence can be:
- Local: in the same breast or in the surgery scar
- Regional: in nearby lymph nodes
- Distant: in a distant part of the body
Treatment for recurrent breast cancer depends on where the cancer comes back and what treatment you had before.
- Written by
- References
Developed by the American Cancer Society medical and editorial content team with medical review and contribution by the American Society of Clinical Oncology (ASCO).
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, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg's Cancer: Principles and Practice of Oncology. 12th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2023.
National Cancer Institute. Physician Data Query (PDQ). Breast Cancer Treatment – Health Professional Version. 2025. Accessed at https://www.cancer.gov/types/breast/hp/breast-treatment-pdq on May 4, 2026.
National Comprehensive Cancer Network (NCCN). Practice Guidelines in Oncology: Breast Cancer. Version 2.2026. Accessed at https://www.nccn.org/professionals/physician_gls/pdf/breast.pdf on May 4, 2026.
Last Revised: July 9, 2026
American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.
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