Breast Cancer Treatment

mature woman discussing treatment options with her doctor

Treatment for breast cancer depends on the type of breast cancer you have, where it’s located, and what stage it is.

Typically, you and your doctor will arrange a plan based on:

  • Tumor type
  • Tumor grade (this indicates how quickly it is likely to grow and spread)
  • Tumor size
  • Number of lymph nodes involved, and degree of involvement
  • Risk of cancer spreading elsewhere in the body

These factors will be taken into consideration with each kind of treatment you need. Other factors, such as your age, whether you’re premenopausal or post-menopausal, and whether the cancer is hormone-sensitive, will also help shape the course of your treatment.

Most breast cancer is treated with surgery, often along with radiation or other treatments to help rid the body of cancer cells.

One or more of the following procedures and treatments may be involved.


Rather than remove an entire breast, surgeons may perform a lumpectomy to remove the tumor and a small cancer-free margin of tissue surrounding it to better prevent recurrence. This procedure is also called breast-conserving surgery.

Lumpectomies are often performed if the cancer is small and in the early stage, or if the cancer is located in the milk ducts (this is a kind of cancer called ductal carcinoma in situ, or DCIS). That is frequently followed by radiation.

Even though it’s the least invasive breast cancer surgery, a lumpectomy can be very effective.

Is a Mastectomy Always Needed When You Have Breast Cancer?

For some, a mastectomy is the only choice, but is that true in all cases? Breast surgical oncologist Ryland Gore, MD, explains.
Is a Mastectomy Always Needed When You Have Breast Cancer?


In a mastectomy, one or both breasts are fully removed. It can also involve removing lymph nodes in the armpit area if the cancer has spread there or is at risk of spreading there, or if there is an invasive tumor.

Mastectomy may be recommended if:

  • The tumor is large.
  • You have multiple tumors in the breast.
  • You have tested positive for mutations in the genes BRCA1 and BRCA2, which can increase the risk of a second cancer.
  • The cancer is recurrent.
  • Not all of the tissue surrounding the cancer was removed in a prior surgery.
  • You have inflammatory breast cancer.
  • You have Paget’s disease, which is a very rare form of breast cancer.
  • The size of the tumor, in relation to breast size, is unfavorable.
  • The tumor is close to what’s called the nipple-areolar complex (which consists of the nipple and the pigmented skin around the nipple).

Sometimes women with small and localized cancers will choose to have this more extensive surgery in order to feel more certain that the cancer won’t come back.


Radiation uses high-energy rays to kill cancer cells in the breast, chest wall, or underarm area after surgery. The aim is to keep the cancer from returning. In general, radiation only treats cells in the area of the body that is being treated.

It’s most commonly used if you’ve had a lumpectomy, but it is sometimes administered after a mastectomy if the tumor is larger than 5 centimeters (2 inches), or if the cancer has spread to several lymph nodes. It may be given to metastatic breast cancer patients to ease symptoms and treat complications like bleeding.

You might be able to forgo radiation after a lumpectomy if you’re 65 or older, your tumor was small, and the cancer is hormone-sensitive and hasn’t spread to the lymph nodes, according to the American Cancer Society.

There are two types of radiation therapy.

  • External Beam Radiation Therapy This is the most common form of radiation, and there are two forms: whole breast and partial breast.
  • Brachytherapy, or Internal Radiation A catheter is implanted in the area where the cancer was removed, and radiation is delivered through radioactive pellets that are inserted in the catheter. This procedure is used if the tumor is small, in an early stage, and shows no signs of having spread, says

A newer type of external radiation therapy, called proton therapy, harnesses the energy of highly energized radiation particles to send a more precise dose of radiation to tumors. Because of its precision, it’s thought to result in fewer side effects and less harm to the areas surrounding the cancer, and it may be recommended if cancer is located close to the heart or lungs.

Length of Treatment

Whole breast radiation is usually given five days a week for three to six weeks. Partial breast radiation can take one to two weeks. Sessions average about 20 minutes each.

Brachytherapy, at low doses, is usually given twice a day for five days in an outpatient setting. High-dose brachytherapy, however, may require you to stay in the hospital for a few days.

Radiation Side Effects

Temporary side effects of external radiation include:

  • Skin changes similar to sunburn (redness, peeling, irritation)
  • Fatigue
  • Swelling or soreness of the breast

Long-term side effects, which may appear later on, may include:

  • Changes to the shape of the breast or the feel of the skin on the breast
  • Lymphedema, or buildup of lymph fluid that causes swelling, usually in the arms or hand
  • Nerve damage in the arm
  • Rib fracture
  • Additional cancers

For breast cancer found on the left side, there’s a risk of radiation exposure to the heart, which can lead to side effects such as arrhythmia.

Side effects of brachytherapy can include:

  • Pain
  • Bruising
  • Infection
  • Damage to fatty tissue
  • Fluid collecting in the breast

If you receive brachytherapy, you may give off radiation for a short amount of time. Hospital staff, visitors, and family might need to keep a certain amount of distance from you during your treatment, but once the implant is removed, you’ll stop giving off radiation. You will not be radioactive if you receive any kind of external beam radiation therapy.


Chemotherapy involves using a combination of drugs to destroy cancer cells or slow down their growth. It is usually administered intravenously (by IV), in an outpatient setting. It can be given before or after breast cancer surgery, or when your cancer is metastatic.

Chemotherapy drugs commonly used for treatment before and after surgery include:

Chemotherapy drugs commonly used in the treatment of metastatic cancer include:

Length of Treatment

Most chemotherapy takes three to six months, and it’s given in cycles. You’ll receive treatment followed by a period of rest that can range from one to three weeks, then treatment again.

The number of chemotherapy treatments for breast cancer depends on the stage and location of the cancer. Some cycles might have only one day of treatment a week, while others might require several days of treatment.

Chemotherapy Side Effects

Chemotherapy may harm healthy cells while it’s treating your cancer, which can lead to temporary and long-lasting side effects.

Temporary side effects can include:

  • Hair loss
  • Changes in appetite or weight
  • Fatigue
  • Nausea
  • Nerve damage
  • Diarrhea or constipation
  • Memory loss
  • Mouth sores
  • Hot flashes
  • Vaginal dryness

More serious side effects can include:

  • Bone loss
  • Heart damage
  • Infertility
  • Leukemia
  • Nerve damage that persists

Hormone Therapy

If your type of cancer is hormone-receptor positive, which about 80 percent of breast cancers are, hormone therapy may be recommended to slow or stop the growth of tumors. This therapy works by interfering with the body’s ability to produce or respond to hormones.

Hormone therapy can be used to shrink and control cancer, or to prevent cancer from returning after other treatments are completed.

Hormone therapy for cancer is different from hormone therapy used to help with symptoms of menopause.

Medications that are used in hormone therapy include:

  • Selective Estrogen Receptor Modulators (SERMs) These are oral medications that block hormones from attaching to cancer cells. Tamoxifen is a SERM, as is raloxifine.
  • Aromatase Inhibitors (AIs) These are oral medications that prevent the body from making estrogen after menopause. The three AIs are anastrozole, exemestane, and letrozole.
  • Injections These stop the ovaries from making estrogen. They are leuprolide (Lupron) and goserelin (Zoladex).
  • Fulvestrant (Faslodex) This is an injection that keeps estrogen receptors from working properly.

Removal of the ovaries may also be recommended.

Length of Treatment

Hormone therapy is administered for 5 to 10 years. The length of time you’re on it and the combination of drugs administered will depend on whether you’re pre- or post-menopausal, what stage the cancer is, and how high the risk of recurrence is.

If you’re post-menopausal, you may receive tamoxifen for several years, then go on an AI for several more. If you’re premenopausal, you might receive tamoxifen alone, or an AI alone, with either drug followed up with ovarian suppression.

Hormonal Therapy Side Effects

Common side effects, which often mimic the symptoms of menopause, can include:

Rare and more serious side effects include:

  • Blood clots
  • Uterine and endometrial cancer
  • Bone thinning
  • Cataracts
  • Heart problems
  • Elevated cholesterol levels

Targeted Therapy

Targeted therapy does what its name suggests: It targets proteins on cancer cells that are instrumental in the development of cancer, in order to keep the cancer from growing.

These therapies, which are given in IV, pill, or injection form, often have fewer side effects than chemotherapy. They can be used alone or in combination with chemotherapy and hormone therapy. They’re often administered when a first course of therapy, such as hormone therapy, stops working, or when the cancer is metastatic.

Biopsies or genetic tests can tell you whether your type of cancer makes you a candidate for targeted therapy.

Targeted therapies currently exist for these types of cancers:

  • HER2-positive
  • Hormone receptor positive
  • BRCA gene mutation
  • Triple negative
  • HER2-low

The following drugs are targeted therapies:

Length of Treatment

Treatment on targeted therapies can last for six months to two years.

Targeted Therapy Side Effects

Some common side effects of these drugs include:

  • Low blood cell counts
  • Elevated blood sugar levels
  • Nausea
  • Vomiting
  • Diarrhea
  • Tiredness

More serious side effects include:

  • Liver problems
  • Heart damage
  • Lung problems
  • Severe diarrhea
  • Harm to unborn fetuses


Immunotherapy teaches the immune system to recognize and respond to cancer cells as foreign invaders and destroy them.

Currently, the only immunotherapy medication approved for breast cancer is Keytruda (pembrolizumab). It’s an IV drug used in combination with chemotherapy to treat triple-negative breast cancer, but can also be used alone, after surgery.

Treatment typically lasts one or two years, and common side effects include fatigue, diarrhea, and bone and joint pain. More serious side effects include lung, liver, and kidney problems.

Breast cancer vaccines are a new form of immunotherapy under investigation at a number of institutions, with several clinical trials focused on triple-negative breast cancer. These have not yet been approved by the U.S. Food and Drug Administration.

Reconstruction Surgery

Most women who have had all or part of a breast removed can have their breast (or breasts) rebuilt to match the size and shape of the other breast or their original breasts, if they choose to.

The nipple and areola (dark area of skin around the nipple) can also be reconstructed.

Over the past decade, there have been significant advancements in breast reconstruction. Reconstructed breasts are often outwardly indistinguishable from a woman’s original breasts.

Additional reporting by Cathy Cassata.

Editorial Sources and Fact-Checking

Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.


  • Breast Cancer: Diagnosis and Treatment.?Mayo Clinic. December 14, 2022.
  • Lumpectomy.?National Breast Cancer Foundation.
  • Radiation Therapy.?National Breast Cancer Foundation.
  • Mastectomy.?Mayo Clinic. October 30, 2021.
  • Should I Get Breast Reconstruction Surgery??American Cancer Society. September 19, 2022.
  • Aromatase Inhibitors for Lowering Breast Cancer Risk. American Cancer Society. December 16, 2021.
  • Hormone Therapy for Breast Cancer. American Cancer Society. October 27, 2021.
  • Breast Cancer Hormone Receptor Status. American Cancer Society. November 8, 2021.
  • Targeted Therapy for Breast Cancer. American Cancer Society. August 25, 2022.
  • Targeted Therapy. National Breast Cancer Foundation.
  • Is Proton Therapy Safer Than Radiation? National Cancer Institute. February 11, 2020.
  • Radiation Therapy for Breast Cancer. Mayo Clinic. October 6, 2022.
  • Brachytherapy to Treat Cancer. National Cancer Institute. January 29, 2019.
  • What Is Brachytherapy? Memorial Sloan Kettering Cancer Center.
  • Partial Breast Brachytherapy. MedlinePlus. July 19, 2020.
  • Breast Cancer Treatment (Adult) PDQ-Patient Version. National Cancer Institute. October 6, 2022.
  • Brachytherapy or Internal Radiation. November 18, 2022.
  • Mastectomy.
  • Immunotherapy.
  • Radiation for Breast Cancer. American Cancer Society. October 27, 2021.
  • About Your External Beam Radiation Therapy to Your Breast or Chest Wall. Memorial Sloan Kettering Cancer Center.
  • Whole Breast Radiation Therapy.?Medline Plus. July 19, 2020.
  • Partial Breast Radiation Therapy. MedlinePlus. July 19, 2020.
  • HER-2 Targeted Therapies for Early Breast Cancer. Susan G. Komen. June 28, 2022.
  • Chemotherapy for Breast Cancer. American Cancer Society. October 27, 2021.
  • Chemotherapy for Breast Cancer. Memorial Sloan Kettering Cancer Center.
  • Chemotherapy Drugs. Susan G. Komen. June 28, 2022.
  • Hormone Therapy for Breast Cancer. National Cancer Institute. July 12, 2022.
  • Hormone Therapy for Breast Cancer. Mayo Clinic. December 29, 2020.
  • Cancer Treatment Centers of America. Breast Cancer Treatments. July 5, 2022.
  • Immunotherapy for Breast Cancer. American Cancer Society. October 27, 2021.
  • Collins LC, Laronga C, Wong JS. Ductal Carcinoma in Situ. November 2022.
  • Salamon M. When Can Women With Early-Stage Breast Cancer Skip Radiation After Lumpectomy? Harvard Health Publishing. September 15, 2022.
  • Treatment of Breast Cancer Stages I-III. American Cancer Society. April 12, 2022.
Show Less