Treatments for stage 3 breast cancer

The following are treatment options for stage 3 ductal carcinoma and lobular carcinoma. Stage 3 is divided into stages 3A, 3B and 3C, which are all considered locally advanced breast cancer. Your healthcare team will suggest treatments based on your needs and work with you to develop a treatment plan.


If you have stage 3A breast cancer and you plan to have breast-conserving surgery, you may be offered chemotherapy before surgery (called neoadjuvant chemotherapy). It is used to shrink the tumour and destroy cancer cells in the lymph nodes.

Chemotherapy is usually given after surgery if you did not have it before surgery. Some women who have neoadjuvant chemotherapy before breast-conserving surgery may be offered more chemotherapy after surgery.

The following combinations of chemotherapy drugs are used for stage 3 breast cancer:

  • AC-T – doxorubicin (Adriamycin) and cyclophosphamide (Procytox) followed by paclitaxel (Taxol) or docetaxel (Taxotere)
  • T-AC – paclitaxel or docetaxel followed by doxorubicin and cyclophosphamide
  • TC – paclitaxel and cyclophosphamide
  • CAF (or FAC) – cyclophosphamide, doxorubicin and 5-fluorouracil (Adrucil, 5-FU)
  • CAF followed by docetaxel or paclitaxel
  • CEF (or FEC) – cyclophosphamide, epirubicin (Pharmorubicin) and 5-fluorouracil
  • CEF followed by docetaxel or paclitaxel
  • EC – epirubicin and cyclophosphamide

Targeted therapy

Trastuzumab (Herceptin) is added to chemotherapy for HER2-positive breast cancer. It is continued for 1 year after chemotherapy is finished.

Pertuzumab (Perjeta) may be used alone or in combination with chemotherapy and trastuzumab before surgery for stage 3 HER2-positive breast cancer. It may also be used alone if surgery isn't done.

Phesgo combines trastuzumab and pertuzumab into a single dose. It is given by a needle just under the skin (subcutaneously) instead of through a needle in a vein (intravenously). This means that treatment can be given more quickly and easily than giving the 2 drugs separately. Phesgo may be used before surgery for stage 3 breast cancer. It is also offered for hormone receptor–positive breast cancer, hormone receptor–negative breast cancer or inflammatory breast cancer.

Palbociclib (Ibrance) may be given along with an aromatase inhibitor in post-menopausal women with estrogen receptor-positive (ER+), HER2-negative stage 3 breast cancer, who have not had trastuzumab or chemotherapy. It can be given as the first treatment for stage 3 breast cancer.

Neratinib (Nerlynx) may be used to treat women with stage 3 hormone receptor-positive and HER2-positive breast cancer after they have completed a year of trastuzumab therapy.

Talazoparib (Talzenna) may be used to treat people with locally advanced, HER2-negative breast cancer who have a BRCA gene mutation. It is used if surgery or radiation can’t be done and they have already had chemotherapy. Talazoparib is taken by mouth once a day.


Surgery is done before or after chemotherapy for stage 3 breast cancer. The following types of surgeries may be done.

Breast-conserving surgery may be offered if chemotherapy shrinks the tumour enough for doctors to completely remove it and leave enough tissue for the breast to look natural. This type of surgery is used most often for stage 3A tumours.

Modified radical mastectomy is done after chemotherapy for stage 3B and stage 3C tumours. It may also be done for stage 3A tumours that don’t respond to chemotherapy.

Axillary lymph node dissection (ALND) is often done to diagnose and stage breast cancer.

Sentinel lymph node biopsy (SLNB) may be done before chemotherapy to find out if cancer has spread to the lymph nodes.

Radiation therapy

External beam radiation therapy is given after breast-conserving surgery. All of the breast, the muscles of the chest, lymph nodes under the arm and lymph nodes around the collarbone are treated. Doctors may also give an extra dose, or boost, of radiation to the area where the tumour was removed.

If you have a mastectomy, radiation therapy may be given to the muscles of the chest, lymph nodes under the arm and lymph nodes around the collarbone.

Hormonal therapy

Hormonal therapy is always offered for hormone receptor–positive stage 3 breast cancer.

Hormonal therapy for post-menopausal women

Hormonal therapy for post-menopausal women with stage 3 breast cancer includes tamoxifen (an anti-estrogen) and aromatase inhibitors.

You may be offered one of the following options:

  • tamoxifen (Nolvadex, Tamofen) alone for up to 10 years
  • an aromatase inhibitor alone for up to 10 years
  • tamoxifen for 5 years, and then an aromatase inhibitor for up to 5 years (for up to a total of 10 years of hormonal therapy)
  • tamoxifen for 2 to 3 years followed by an aromatase inhibitor for 2 to 3 years, or starting with an aromatase inhibitor followed by tamoxifen, for a total of 5 years of hormonal therapy
  • an aromatase inhibitor for 2 to 3 years, followed by tamoxifen

Hormonal therapy for premenopausal women

Hormonal therapy options for premenopausal women with stage 3 breast cancer include the following.

You may take tamoxifen for 5 years, then your healthcare team will check if you have reached menopause.

  • If you are still premenopausal, you can continue to take tamoxifen for up to 10 years in total.
  • If you have reached menopause, your healthcare team may offer you the option to continue tamoxifen for up to 10 years in total or to switch to an aromatase inhibitor for up to 5 years (for up to a total of 10 years of hormonal therapy).

You may take ovarian ablation or suppression, along with tamoxifen or an aromatase inhibitor, for up to 10 years.

Clinical trials

Many clinical trials in Canada are open to women with breast cancer. Clinical trials look at new ways to prevent, find and treat cancer. Find out more about clinical trials.

Expert review and references

  • Hoffman La-Roche Limited Canada. Product Monograph Pertuzumab (Perjeta).
  • American Cancer Society. Breast Cancer. 2015:
  • Brackstone M, Fletcher GG, Dayes IS, Madarnas Y, SenGupta SK, Verma S, and Members of the Breast Cancer Disease Site Group . Locoregional therapy of locally advanced breast cancer: a clinical practice guideline. Current Oncology. 2015.
  • Burstein HJ, Temin S, Anderson H, Buchholz TA, Davidson NE, Gelmon KE, Giordano SH, et al . Adjuvant endocrine therapy for women with hormone receptor-positive breast cancer: American Society of Clinical Oncology clinical practice guideline focused update. Journal of Clinical Oncology. 2014.
  • Roche Canada. Product Monograph Trastuzumab Emtansine (Kadcyla).
  • Goss, PE, Ingle JN, Pritchard KJ, et al . Extending aromatase-inhibitor adjuvant therapy to 10 years. New England Journal of Medicine. 2016.
  • Joy AA, Ghosh M, Fernandes R, Clemons MJ . Systemic treatment approaches in HER2-negative advanced breast cancer - guidance on the guidelines. Current Oncology. 2015.
  • Morrow M, Burstein HJ, and Harris JR . Malignant tumors of the breast. DeVita VT Jr, Lawrence TS, & Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 79: 1117-1156.
  • National Cancer Institute. Breast Cancer Treatment for Health Professionals (PDQ®). 2015.
  • National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Breast Cancer (Version 2.2015).

Medical disclaimer

The information that the Canadian Cancer Society provides does not replace your relationship with your doctor. The information is for your general use, so be sure to talk to a qualified healthcare professional before making medical decisions or if you have questions about your health.

We do our best to make sure that the information we provide is accurate and reliable but cannot guarantee that it is error-free or complete.

The Canadian Cancer Society is not responsible for the quality of the information or services provided by other organizations and mentioned on, nor do we endorse any service, product, treatment or therapy.

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