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Breast Cancer: Treatment and Prevention Options

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on April 15, 2024.

Overview: How Common is Breast Cancer?

Breast cancer is the most common cancer in the U.S. with the exception of skin cancer. Currently, the average risk of developing breast cancer over a lifetime is 13% (a 1 in 8 chance). The good news is that today, 90% of women with breast cancer are still alive five years after their diagnosis due to earlier detection and advanced treatment options.

The primary risk factors for having breast cancer diagnosis include being a woman and older age, with most breast cancers occurring after the age of 50. The median age at the time of diagnosis in a women is 62 years.

Men can also develop breast cancer. In 2023, breast cancer comprised 15% of all newly diagnosed cancers, with about 298,000 women and 2,800 men being diagnosed. Around 43,000 women and 530 men died from breast cancer in 2023.

Woman with breast cancer undergoing treatment

Treatment of Breast Cancer

Treatment of breast cancer often requires a multifactorial approach, using surgery, radiation and medications. Breast cancer may be treated with local therapy, systemic therapy, or both.

Chemotherapy and HER2 inhibitors, if indicated, are often the selected agents used prior to surgery; however, many people will not need chemotherapy before surgery.

Learn More: What is Breast Cancer? An Overview

Surgery and Radiation

Surgery is the most common treatment for breast cancer, and there are several types:

In most cases, the surgeon also removes lymph nodes under the arm to help determine whether cancer cells have entered the lymphatic system. This is called an axillary lymph node biopsy.

In certain cases, a sentinel lymph node biopsy may be needed, where the lymph node closest to the tumor is removed to determine if cancer has spread to other places in your body. By knowing this information, your doctor can better select your best treatment.

Risks of surgery

Breast cancer surgery causes short-term pain and tenderness in the area of the operation and also carries a risk of infection, poor wound healing, bleeding, or a reaction to the anesthesia used during surgery.

Removal of a breast can cause a weight imbalance, which can result in discomfort in the neck and back. Skin in the area where the breast was removed may be tight, the muscles of the arm and shoulder may feel stiff. Nerves that may be injured or cut during surgery can cause numbness and tingling in the chest, underarm, shoulder, and upper arm. These feelings usually go away within a few weeks or months.

Your surgeon will outline the specific risks associated with your surgery, the timelines for recovery, and any follow-up appointments you may need.

Radiation therapy

Radiation therapy (radiotherapy) is the use of high-energy rays to kill cancer cells. The radiation may be directed at the breast by a machine (external radiation), or may come from radioactive material placed in thin plastic tubes that are placed directly in the breast (implant radiation). Sometimes, both types of radiation therapy are used.

Before surgery, radiation therapy, alone or with chemotherapy or hormonal therapy, is sometimes used to destroy cancer cells and shrink tumors. This approach is most often used in cases in which the breast tumor is large or not easily removed by surgery.

Radiation side effects can occur. During radiation therapy, patients may become extremely tired, especially after several treatments. It is also common for the skin in the treated area to become red, dry, tender, and itchy. The breast may feel heavy and hard, but these conditions will clear up with time. Toward the end of treatment, the skin may become moist and weepy but exposing this area to air as much as possible will help the healing process.


Chemotherapy is the use of drugs to kill cancer cells. Chemotherapy for breast cancer is usually a combination of drugs given in a pill or by injection.

The side effects of chemotherapy depend mainly on the specific drugs and the dose. These include:

In general, anti-cancer drugs affect rapidly dividing cells. Many of these side effects can now be controlled, thanks to other new or improved medications. Side effects generally are short-term and gradually go away. Hair almost always grows back, but it may be different in color and texture.

Hormone therapy

Hormonal (endocrine) therapy prevents the growth of hormone dependent cancer cells. This treatment may include the use of drugs, or surgery to remove the ovaries and possibly the fallopian tubes (oophorectomy or salpingo-oophorectomy). Hormone therapy is not the same thing as hormone-replacement therapy to lessen symptoms from menopause such as hot flashes and vaginal dryness.

Medications used in this type of adjuvant treatment are typically the selective estrogen receptor modulators (SERMs) or aromatase inhibitors (AIs). These agents block estrogen’s ability to fuel breast cancer. This treatment has been shown to reduce the risk of recurrence and death from breast cancer in hormone receptor-positive women. These are usually oral medications taken daily for 5 to 10 years.

The side effects of hormonal therapy depend largely on the specific drug or type of treatment. For example, tamoxifen, one of the most common hormonal treatments, may cause hot flashes, vaginal discharge or irritation, nausea, mood changes, and irregular periods.


Biologic therapy is a treatment designed to enhance the body's natural defenses against cancer. For example, monoclonal antibodies can target breast cancer cells that have too much of a protein known as human epidermal growth factor receptor-2 (HER2). Blocking HER2 slows or stops the growth of these cells.

The side effects of biological therapy differ with the types of substances used, and from patient to patient. Rashes or swelling where the biological therapy is injected are common. Flu-like symptoms also may occur.

Common Drugs Used in the Treatment of Breast Cancer

Hormone (Endocrine) Therapy

Estrogen or progesterone, naturally occurring female hormones, can fuel breast cancers known as hormone receptor (HR+) positive cancers. These cancers are often treated with a type of hormone therapy that blocks the cancer from getting the estrogen or progesterone or slows down the production. Most breast cancers, about 80%, are hormone receptor-positive.

Endocrine therapy include aromatase inhibitors (AIs), selective estrogen receptor modulators (SERMs), and the estrogen receptor antagonists fulvestrant (Faslodex) and elacestrant (Orserdu), also called anti-estrogens or a selective estrogen receptor degraders (SERDs). AIs and SERMs are all given orally, fulvestrant (Faslodex) is given by intramuscular injection, and Orserdu is an oral tablet.

Hormone therapy is used for most HR+ breast cancers and is often the first treatment given. It may be prescribed before surgery, after surgery, or if the cancer returns later. Selection of which drug is based on whether you are pre- or postmenopausal. They are usually taken for 5 to 10 years.

Generic name Brand name examples Use
anastrozole Arimidex Postmenopausal; early/locally advanced or metastatic disease
elacestrant Orserdu Postmenopausal women or adult men; ERpositive, HER2-negative, ESR1-mutated advanced or metastatic disease with progression after at least one line of endocrine therapy
exemestane Aromasin Postmenopausal; early/locally advanced or metastatic disease
fulvestrant Faslodex Postmenopausal; advanced or metastatic disease
toremifene Fareston Postmenopausal; metastatic disease
letrozole Femara Postmenopausal; early/locally advanced or metastatic disease
tamoxifen Soltamox Pre- and postmenopausal; early/locally advanced or metastatic disease

How do aromatase inhibitors work?

Aromatase inhibitors (AIs) are used to treat HR+ early, locally advanced and metastatic (has spread in the body) breast cancers. Aromatase inhibitors (AIs) work by blocking estrogen production in postmenopausal women with HR+ breast cancer. After menopause, estrogen can still be made in fat cells, adrenal glands and the liver.

AIs in women with HR+ breast cancer can:

AIs do not block estrogen production from the ovaries, so they must be used with ovarian suppression in premenopausal women. Ovarian suppression can occur with surgery by removing the ovaries, which is permanent, or by using a medication for ovarian suppression, which is temporary.

How do selective estrogen receptor agents work?

SERMs or SERDs work to either block the estrogen receptors (ER) so that estrogen cannot have an effect to fuel the cancer, or both block and destroy the estrogen receptor.

Orserdu, the latest approved SERD, works by blocking the effect of estrogen on the hormone receptor-positive breast cancer cells. It binds to and inhibits the activity of the estrogen receptor-alpha (ERα) and promotes its breakdown.


Chemotherapy (“chemo”) drugs work in breast cancer by disrupting the life cycle of the cancer cell. Most people receive chemotherapy for breast cancer after they’ve had surgery, but you might receive it before surgery to help shrink your tumor in some cases. Chemotherapy is a treatment option for most forms of breast cancer. It can be used for treating early and locally advanced breast cancer as well as metastatic disease. Chemotherapy might also be called antineoplastic or cytotoxic therapy.

Neoadjuvant chemotherapy is chemotherapy given before surgery to shrink the tumor size. Adjuvant chemotherapy is therapy given after surgery, but before radiation treatment, and helps to kill any remaining cancer cells.

How are chemotherapy drugs given?

Chemotherapy drugs are typically given by mouth (oral) or by injection into the vein. You may receive treatment daily, weekly, or every few weeks. They are often used in two or three drug regimens, either together or one after another, so you might receive both an oral and an injected drug. Chemotherapy is usually given in cycles over a period of 3 to 6 months. You will have several days or weeks off between treatments, which will help your cells to recover.

There are many classes of chemotherapy used in breast cancer treatment. Your combination of drugs determines your treatment schedule. Your doctor may call these regimens by abbreviations such as “AC” (Adriamycin and Cytoxan) or “CAF” (Cytoxan, Adriamycin, and fluorouracil), or TAC (docetaxel, doxorubicin and cyclophosphamide). Targeted drugs, such as trastuzumab (Herceptin), pertuzumab (Perjeta) or neratinib (Nerlynx) may also be used in HER2+ breast cancer regimens along with chemotherapy agents

Your physician will explain your treatment plan and schedule for you. The choice is very individualized and based on your specific circumstances. Your treatment plan will be based upon the stage and characteristics of the cancer, your previous treatments, your age, your preferences, and other patient specific information, such as interactions with other medications you take or health conditions you might have.


Generic name Brand name examples
doxorubicin, doxorubicin liposomal Adriamycin (brand discontinued), Doxil
epirubicin Ellence

Alkylating agents and Platinum Analogs

Generic name Brand name examples
carboplatin Not available
cyclophosphamide Cytoxan (brand discontinued)
thiotepa Tepadina


Generic name Brand name examples
capecitabine Xeloda
fluorouracil (5-FU) Adrucil (brand discontinued)
gemcitabine Gemzar, Infugem
methotrexate (MTX) Otrexup, Rasuvo, Trexall

Mitotic Inhibitors

Generic name Brand name examples
docetaxel Taxotere
eribulin Halaven
ixabepilone Ixempra
paclitaxel Taxol (brand discontinued)
paclitaxel, protein-bound Abraxane
vinblastine Velban

HER2 Inhibitors

Generic name Brand name examples
ado-trastuzumab emtansine Kadcyla
hyaluronidase and trastuzumab Herceptin Hylecta
fam-trastuzumab deruxtecan Enhertu
hyaluronidase, pertuzumab, and trastuzumab Phesgo
lapatinib Tykerb
margetuximab-cmkb Margenza
neratinib Nerlynx
pertuzumab Perjeta
trastuzumab Herceptin
trastuzumab-anns (biosimilar) Kanjinti
trastuzumab-dkst (biosimilar) Ogivri
trastuzumab-dttb (biosimilar) Ontruzant
trastuzumab-pkrb (biosimilar) Herzuma
trastuzumab-qyyp (biosimilar) Trazimera
tucatinib Tukysa

CDK 4/6 Inhibitors

Generic name Brand name examples
abemaciclib Verzenio
palbociclib Ibrance
ribociclib Kisqali

Mammalian Target of Rapamycin (mTOR) Inhibitors

Generic name Brand name examples

Afinitor, Afinitor Disperz

Note: Zortress is another brand of everolimus used to prevent organ rejection after a kidney transplant. It is not used for breast cancer treatment.

Phosphatidylinositol-3-Kinase (PI3K) Inhibitor

Generic name Brand name examples


Note: Vijoice is another brand for alpelisib used to treat phosphatidylinositol-3-kinase catalytic subunit alpha (PIK3CA)-Related Overgrowth Spectrum (PROS). It is not approved for breast cancer treatment.

Poly (ADP-ribose) polymerase (PARP) inhibitors

Generic name Brand name examples
olaparib Lynparza
talazoparib Talzenna

Poly (ADP-ribose) polymerase (PARP) inhibitors, also called PARP inhibitors, are used to treat cancers that have errors in their DNA repair genes.

Tropomyosin Receptor Kinase (TRK) Inhibitor

Generic name Brand name examples
larotrectinib Vitrakvi

Trop-2-directed Antibody-Drug Conjugate

Generic name Brand name examples
sacituzumab govitecan-hziy Trodelvy

AKT Inhibitors

Generic name Brand name examples
capivasertib Truqap

Anti-PD-1 Monoclonal Antibodies

Immunotherapy or biologic therapy such as anti-PD-1 monoclonal antibodies are some of the latest advances in breast cancer treatment and cancer treatment overall. These drugs may also be called immune checkpoint inhibitors.

Some of these checkpoints are called PD-1, PD-L1, and CTLA-4 receptors, which are protein receptors or ligands on cell surfaces. By blocking these receptor sites, immunotherapy can help boost the body's own immune system to further fight many types of cancer.

Side effects with anti-PD-1 therapies vary based on drug and other combined treatments: common side effects can include: fatigue, muscle or joint pain, decreased appetite, itching, diarrhea, nausea, rash, fever, cough, shortness of breath, constipation, and stomach pain, among others.

Generic name Brand name examples
pembrolizumab Keytruda

Learn more: How is Keytruda given?

Breast Cancer Prevention in Women at High Risk

Some women who have not previously been diagnosed with breast cancer may be determined to be at higher risk for developing breast cancer. This can be determined by an assessment done by your doctor looking at your risk factors. A discussion of options for breast cancer risk reduction may be warranted with your physician.

However, risk factor assessment cannot predict with 100% accuracy if you will, or will not, develop breast cancer. It is important to discuss your possible risk factors with your doctor. It is also important to weigh the risk of taking a medication long-term versus the predicted risk for getting breast cancer.

Factors that affect breast cancer risk include:

All of the preventive agents recommended by the American Society of Clinical Oncology (ASCO) as of September 2019 work to prevent only estrogen receptor (ER) positive tumors.

Medications Used to Help Prevent Invasive Breast Cancer in Women at High Risk

Generic name Brand name examples Use
anastrozole Arimidex Postmenopausal
exemestane Aromasin Postmenopausal
raloxifene Evista Postmenopausal
tamoxifen Soltamox Premenopausal; Postmenopausal

These include the selective estrogen receptor modulators (SERMs) tamoxifen or raloxifene, or the aromatase inhibitors (AIs) anastrozole or exemestane. Raloxifene (Evista) is given to lower the risk of invasive breast cancer in postmenopausal women with osteoporosis, or other postmenopausal women at risk of invasive breast cancer. Evista is not a cancer medication and will not treat breast cancer.

These medications are typically given for 5 years or longer, and can lower the risk of breast cancer development by 40% to 65%. The cancer prevention effects last long-term, even after the medication is stopped.

The choice of which agent you use will depend upon if you have been through menopause, the side effect profile of each medication, past medical history, and cost concerns or insurance coverage.

Premenopausal women typically use tamoxifen, while postmenopausal women can use either tamoxifen or the aromatase inhibitors (AIs). AIs are not used in premenopausal women with ovaries as they may elevate estrogen production, which can further increase risk for breast cancer.

The side effects of these drugs used over 5 years or longer should be discussed with your doctor. Depending upon which drug you use, these effects may include:

In some women at high risk, a breast MRI may be used as a preventive tool for breast cancer detection. A breast MRI is used with a mammogram to image your breasts, not as a replacement for a mammogram.

Triple-negative breast cancer is the most common type of breast cancer found in women with BRCA1 mutations. Triple negative breast cancer is hormone negative (estrogen receptor/progesterone receptor negative) and HER2-negative but has abnormal BRCA genes, as determined by a genetic test.

Women with a very high risk of breast cancer, for example with BRCA gene mutations, may decide to have their breasts and/or ovaries surgically removed to help prevent the occurrence of breast cancer and ovarian cancer. This is a significant decision that should only be made in conjunction with a genetic specialist, oncologist and surgeon.

Lifestyle Changes for Breast Cancer Prevention

Even if you are not at a higher than average risk for breast cancer development, there are lifestyle changes that you can implement to help maintain a normal risk for breast cancer.

Latest Research in the Treatment of Breast Cancer

Many studies of new approaches for patients with breast cancer are underway. Current areas of research and treatment advances include:

Those who are interested in learning about ongoing breast cancer clinical trials should speak to their doctor and call 1-855-216-0127 or visit

See also


Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.