Stage 3 breast cancer treatment typically includes surgery and often involves several other therapies.

If you’ve received a stage 3 breast cancer diagnosis, the cancer has one or many of the following features:

  • the tumor might be larger than 5 centimeters (about 2 inches) across
  • the tumor is growing into the skin over the breast or the muscle just underneath that skin
  • the cancer has spread to many axillary (armpit) lymph nodes

Treating stage 3 breast cancer involves surgical removal of the tumor and surrounding tissue. Typically, it also includes systemic therapy to remove cancer cells from the body. Radiation and chemotherapy are also common treatment approaches.

Some people, depending on their subtype of breast cancer, may also receive targeted therapy for 1 year or more after active treatment to prevent the cancer coming back.

If treatment stops working, you can discuss your options with your doctor.

Stage 3 breast cancer treatment can involve a few different therapies. Your doctor will recommend a therapeutic combination based on:

  • the subtype of breast cancer, such as hormone receptor-positive vs. triple-negative vs. HER2-positive
  • the number and type of lymph nodes with cancer, such as axillary, clavicular, or internal mammary
  • whether you have had prior therapy with certain cancer medications
  • whether the cancer is likely to return
  • whether you have a genetic variant, such as a BRCA mutation
  • whether breast-conserving surgery is an option

Surgery

Surgery is usually a part of stage 3 breast cancer treatment. Some people have surgery first, while others have other treatments to try to shrink the tumor before getting surgery.

Types of surgery for stage 3 breast cancer include:

  • Breast-conserving surgery: This type of surgery removes the cancer and some parts of the breast around it.
  • Mastectomy: This surgery removes the entire breast.
  • Lymph node dissection: This surgery removes the axillary (armpit) lymph nodes, which may then be tested to detect the presence of cancer cells.

Radiation therapy

Radiation is typically done after surgery for stage 3 breast cancer. Radiation is high energy rays or particles that destroy cancer cells. There are two main types of radiation for breast cancer treatment:

  • External beam radiation therapy: A machine sends radiation to target your cancer. Your body does not touch the machine.
  • Brachytherapy: A doctor inserts radioactive pellets or seeds into the breast tissue at the site of the tumor removal. This is also called internal radiation.

Doctors choose where to aim radiation based on the type of surgery and the risk of the cancer coming back.

For example, if you have breast-conserving surgery, you might receive whole breast radiation. After those radiation treatments end and there’s a high risk of recurrence, you might get extra radiation where the cancer was removed.

Chemotherapy

Chemotherapy is a type of drug therapy in which medications are given through a vein or by mouth. The drugs move through the bloodstream to target cancer cells.

For stage 3 breast cancer, chemotherapy is often neoadjuvant (before surgery) treatment, although not always. The goal is to shrink the tumor so less tissue has to be removed.

In some people, this might mean having the option of breast-conserving surgery if they prefer not to get a mastectomy.

Targeted therapy

Targeted therapy is a special kind of drug therapy. It works on specific proteins in cancer cells. Because not every type of breast cancer cell has these proteins, you can only benefit from targeted therapy if you have certain types of breast cancer.

Here are some targeted therapies that someone might receive for stage 3 breast cancer:

  • Trastuzumab (Herceptin): Herceptin is for HER2-positive tumors. It’s given before surgery with chemotherapy. Some people might also continue Herceptin after surgery for up to 1 year.
  • Pertuzumab (Perjeta): Perjeta is also for HER2-positive tumors. It might be combined with Herceptin before surgery. It might also be continued for up to 1 year after surgery.
  • Ado-trastuzumab emtansine (Kadcyla): Kadcyla is given instead of Herceptin for up to 1 year after surgery if Herceptin was a neoadjuvant therapy and there was residual cancer at the time of surgery.
  • Neratinib (Nerlynx): Nerlynx is for people with hormone receptor-positive cancer in the lymph nodes who have already completed 1 year of Herceptin. Nerlynx is given for an additional year after the year of Herceptin.
  • Abemaciclib (Verzenio): Verzenio is for people with hormone receptor-positive, HER2-negative breast cancer that’s in the lymph nodes and has a high likelihood of returning. It can be given with hormone therapy for 2 years after surgery.
  • Olaparib (Lynparza): Lynparza is for people with a BRCA mutation, hormone receptor-positive cancer, and HER2-negative cancer and who still have cancer in the tissue removed at surgery after neoadjuvant chemotherapy. It’s taken for 1 year.

Hormone therapy

Hormone therapy is a type of therapy that stops the growth of hormone receptor-positive tumors by stopping the effects of hormones on cancer cells or by changing how the body makes hormones.

People with hormone receptor-positive cancers get hormone therapy at the same time as trastuzumab (Herceptin). In cases when people are taking abemaciclib, doctors typically combine it with a hormonal therapy, such as with:

Immunotherapy

Pembrolizumab (Keytruda) is a type of drug that stimulates the immune system to fight cancer. It is an option for people with stage 3 triple-negative breast cancer.

The timeline of breast cancer treatment is different for every person. For most people with stage 3 breast cancer, active treatment lasts about 1 year, including presurgery (neoadjuvant) treatment. In addition, you might have targeted treatments for 1 to 2 years, depending on the type of therapy.

Each type of treatment has its own side effects. Many of these, such as fatigue or nausea, might end once treatment is over.

Sometimes, there are long-term side effects of breast cancer treatment, such as osteoporosis, lymphedema, and longer-term fatigue.

Survival rates for breast cancer use data from large numbers of people to estimate a person’s chance of surviving cancer at a given stage. Because survival rates are only estimates, they don’t predict your individual outlook after a diagnosis.

Later stage breast cancers are either regional or distant. Regional cancer is when the cancer has spread to nearby lymph nodes. Distant cancer is when the cancer has spread to distant sites in the body.

According to the National Cancer Institute, the 5-year relative survival rates for these stages are:

  • 86.7% for regional
  • 31.9% for distant

Five-year relative survival rates compare people with a certain condition 5 years after diagnosis with those who do not have that condition.

After you have finished breast cancer treatment, your care team will schedule follow-up appointments. These visits can help you manage any symptoms. They also allow your doctors to monitor for any recurrence of the cancer.

If you have symptoms or a finding on a physical exam that suggests breast cancer has come back, your doctor might order blood tests or imaging tests, like a CT or PET scan, to check for recurrence.

Signs it’s time to try a new treatment method

If your treatment ends and your cancer comes back, it might be time to try a different method for treating the cancer.

Similarly, if treatment has not stopped the cancer from growing, your doctor might suggest looking at different treatment strategies.

If you’re experiencing any side effects, discuss them with a doctor. They can prescribe additional medications to help ease those effects while you still continue with your breast cancer treatment.

There are many treatments for stage 3 breast cancer, and many are specific to the type of tumor. Most people have surgery and a combination of drug treatments. If one treatment doesn’t work or stops working, you have options. Be sure to discuss your needs with your care team.