Treatment overview
In cancer care, different types of doctors often work together to create a patient’s overall treatment plan that combines different types of treatments. This is called a multidisciplinary team. Cancer care teams include a variety of other health care professionals, such as physician assistants, oncology nurses, social workers, pharmacists, counselors, dietitians, and others. Ask the doctor in charge of your treatment which health care professionals will be part of your treatment team and what they do. This can change over time as your health care needs change
A treatment plan is a summary of your cancer and the planned cancer treatment. It is meant to give basic information about your medical history to any doctors who will care for you during your lifetime. Before treatment begins, ask your doctor for a copy of your treatment plan. You can also provide your doctor a copy of the ASCO Treatment Plan form to fill out.
The primary goals of metastatic breast cancer treatment are to ensure that you have the:
- Longest survival possible with the disease
- Fewest possible side effects from the cancer and its treatment
- Best and longest quality of life possible
There is no cure for metastatic cancer, but a good quality of life is possible for months or even years.
Treatment options for metastatic breast cancer vary based on:
- Where in the body the cancer has spread
- The presence and level of hormone receptors and/or HER2 in the tumor
- Gene mutations in the tumor
- Specific symptoms
- Previous cancer treatments
- Your overall health
How well treatment works depends on many factors as well, including how widespread the cancer is and what treatments have already been used. Because it is not unusual for metastatic breast cancer to stop responding to drugs, you may need to change treatments fairly often.
After testing is done, you and your doctor will talk about your treatment options. Your treatment plan may include certain treatments described below, but they may be used in a different combination or at a different pace.
Take time to learn about all of your treatment options and be sure to ask questions about things that are unclear. Talk with your doctor about the goals of each treatment and what you can expect while receiving the treatment. Learn more about making treatment decisions.
Systemic therapy
Systemic therapy is often used to treat metastatic breast cancer. This kind of treatment, which is taken by mouth or through a vein, gets into the bloodstream to reach cancer cells throughout the body. There are 3 general categories of systemic therapy used for metastatic breast cancer:
- Hormonal therapy
- Chemotherapy
- Targeted therapy
Each treatment is described below in more detail. Treatment options are based on information about the cancer and your overall health and treatment preferences.
Hormonal therapy
Hormonal therapy, also called endocrine therapy, is an effective treatment for many tumors that test positive for either ER or PR.
Hormone receptor-positive tumors may use hormones to fuel their growth. The goal of this type of therapy is to lower the levels of estrogen and progesterone in the body or to block these hormones from getting to cancer cells. If the hormones cannot get to the cancer cells, the cancer cannot use them to grow.
The choices of hormonal therapy vary depending on whether a woman is still menstruating or has gone through menopause. Hormonal therapy options also depend on what treatments a person has already received. Options for hormonal therapy include:
- Tamoxifen. Tamoxifen is a drug that blocks estrogen from binding to breast cancer cells. It is a pill taken daily by mouth. Common side effects of tamoxifen include hot flashes as well as vaginal discharge or bleeding. Very rare risks include a cancer of the lining of the uterus, cataracts, and blood clots. However, tamoxifen may improve bone health and cholesterol levels. The treatment is an option for both premenopausal and postmenopausal women.
- Aromatase inhibitors (AIs). AIs decrease the amount of estrogen made by tissues other than the ovaries in women who have gone through menopause by blocking the aromatase enzyme. This enzyme changes hormones called androgens into estrogen when the ovaries have stopped making estrogen after menopause. These drugs include anastrozole (Arimidex), exemestane (Aromasin), and letrozole (Femara). All of the AIs are pills taken daily by mouth.Side effects of AIs may include joint stiffness, sometimes with joint aches. AIs may also cause hot flashes, vaginal dryness, an increased risk of osteoporosis and broken bones, and increased cholesterol levels. Research shows that all 3 AI drugs work equally well and have similar side effects. However, women who experience too many side effects while taking 1 AI may have fewer side effects with another AI for unclear reasons. Women who have not gone through menopause should not take AIs, as they do not block the effects of estrogen made by the ovaries. Often, doctors will monitor blood estrogen levels in women whose periods have recently stopped, or those whose periods stop with chemotherapy, to be sure that the ovaries are no longer producing estrogen.
- Ovarian suppression. This is the use of drugs or surgery to stop the ovaries from producing estrogen. It may be used in combination with tamoxifen or an AI. Drugs called gonadotropin or luteinizing releasing hormone (GnRH or LHRH) analogs can stop the ovaries from making estrogen, causing temporary menopause. Surgery permanently stops estrogen production. Ovarian suppression is commonly used to treat hormone receptor-positive metastatic breast cancer in premenopausal women, as complete estrogen suppression may be helpful against the cancer.
- Fulvestrant (Faslodex). Fulvestrant is a selective estrogen receptor downregulator (SERD). That means it binds to the estrogen receptors, blocking the ability of estrogen to attach to these receptors. Unlike other oral hormonal therapies, fulvestrant is given monthly by an injection into a muscle. Most commonly, 2 injections are given every 2 weeks for 3 doses and continued monthly. Fulvestrant is a medication for postmenopausal women only.
- Other hormonal therapies. Other hormonal therapies occasionally used to treat metastatic breast cancer after AIs, fulvestrant, tamoxifen, and targeted therapy (see below) include megestrol acetate (Megace) and high-dose estradiol, which is an estrogen replacement.
Chemotherapy
Chemotherapy is the use of drugs to destroy cancer cells, usually by ending the cancer cells’ ability to grow and divide. Chemotherapy is prescribed by a medical oncologist, a doctor who specializes in treating cancer with medication.
Common ways to give chemotherapy include an intravenous (IV) tube placed into a vein using a needle or in a pill or capsule that is swallowed (orally).
Chemotherapy for metastatic breast cancer can be given on many different schedules depending on what worked best in clinical trials for that specific type of regimen, or schedule. It may be given once a week, once every 2 weeks (also called dose-dense), once every 3 weeks, or even once every 4 weeks. Weekly schedules often include weeks off as a break. In general, chemotherapy is often given continuously as long as it is working against the cancer and as long as the patient isn’t experiencing too many side effects.
A patient with metastatic breast cancer usually receives 1 drug at a time, which means 1 after another, rather than as a combination, although occasionally a combination regimen is recommended. The best chemotherapy option for each patient depends on several factors, including the previous treatment received, potential side effects, the patient’s overall health, and the patient’s preferences.
Drugs that may be used for metastatic breast cancer include:
- Capecitabine (Xeloda)
- Carboplatin (Paraplatin)
- Cisplatin (Platinol)
- Cyclophosphamide (Neosar)
- Docetaxel (Docefrez, Taxotere)
- Doxorubicin (Adriamycin)
- Pegylated liposomal doxorubicin (Doxil)
- Epirubicin (Ellence)
- Eribulin (Halaven)
- Fluorouracil (5-FU, Adrucil)
- Gemcitabine (Gemzar)
- Irinotecan (Camptosar)
- Ixabepilone (Ixempra)
- Methotrexate (multiple brand names)
- Paclitaxel (Taxol)
- Protein-bound paclitaxel (Abraxane)
- Vinorelbine (Navelbine)
Chemotherapy may be combined with other types of treatments. For example, therapies that target the HER2 receptor, such as the antibody trastuzumab, may be given with chemotherapy for HER2-positive breast cancer (see Targeted therapy, below).
The side effects of chemotherapy depend on the individual, the drug(s) used, and the schedule and dose used. These side effects can include fatigue, risk of infection, nausea and vomiting, hair loss, loss of appetite, numbness from nerve damage, and diarrhea. These side effects can often be very successfully prevented or managed during treatment with supportive medications, and they usually go away after treatment is finished.
Many patients feel reasonably well during chemotherapy treatment and are active taking care of their families, traveling, and exercising during treatment, although each person’s experience can be different. Talk with your health care team about the possible side effects of your specific chemotherapy plan.
Learn more about the basics of chemotherapy and preparing for treatment. The medications used to treat cancer are continually being evaluated. Talking with your doctor, oncology nurse, or pharmacist is often the best way to learn about the medications prescribed for you, their purpose, and their potential side effects or interactions with other medications. Learn more about your prescriptions by using searchable drug databases.
Targeted therapy
Targeted therapy is a treatment that targets the cancer’s specific genes, proteins, or the tissue environment that contributes to cancer growth and survival. These treatments are very focused and work differently than chemotherapy or hormonal therapy. This type of treatment blocks the growth and spread of cancer cells while limiting damage to healthy cells.
Recent studies show that not all tumors have the same targets. To find the most effective treatment, your doctor may run tests to identify the genes, proteins, and other factors in your tumor. This helps doctors better match each patient with the most effective treatment whenever possible. In addition, many research studies are taking place now to find out more about specific molecular targets and new treatments directed at them. Learn more about the basics of targeted treatments.
There are different types of targeted therapies that vary in how they target the cancer cells:
- Monoclonal antibodies. A monoclonal antibody is a type of targeted therapy. It recognizes and attaches to a specific protein in the cancer cells, and it does not affect cells that don’t have that protein. Examples of monoclonal antibodies used for breast cancer include trastuzumab, pertuzumab, and TDM-1 (see below).
- Small molecule inhibitors. Small molecule inhibitors are drugs designed to specifically target parts of a cancer cell that contribute to its growth and survival. The parts of a cancer cell that these drugs target may be receptors on the outside of the cell, enzymes on the inside of a cell, or a protein important for cell growth. Some of these types of drugs may target different parts of a cell. These are called “multi-targeted.” Small molecule inhibitors are often pills. Examples used for breast cancer include lapatinib, palbociclib, ribociclib, and everolimus (see below).
Talk with your doctor about possible side effects of specific targeted therapies and how they can be managed.
Targeted therapy for metastatic HER2-positive breast cancer
HER2-targeted therapies can be used to treat HER2-positive metastatic breast cancer. Some of these drugs may be used together with chemotherapy. In general, for a person with HER2-positive metastatic breast cancer, there is almost always a HER2-targeted therapy being used along with another systemic therapy.
Some of the HER2-taregted therapies may not penetrate into the brain as easily as the rest of the body. So, HER2-positive metastatic breast cancer that has spread to the brain is often treated with surgery and/or radiation therapy (see below).
- Trastuzumab (Herceptin). For metastatic breast cancer, trastuzumab can be given in combination with different types of chemotherapy or with endocrine therapy. Trastuzumab can be given as a weekly infusion, or once every 3 weeks. Patients receiving trastuzumab have a small (2% to 5%) risk of heart problems and should have monitoring with an echocardiogram every few months.
- Pertuzumab (Perjeta). Research shows that adding pertuzumab to trastuzumab and chemotherapy as part of first-line therapy for HER2-positive metastatic breast cancer lengthens lives with few additional side effects. Based on this data, the combination of trastuzumab, pertuzumab, and chemotherapy has become a standard of care for the first-line treatment of untreated metastatic HER2-positive breast cancer. Pertuzumab is an intravenous medication and generally causes few side effects, although it can occasionally cause diarrhea.
- Ado-trastuzumab emtansine or T-DM1 (Kadcyla). This is approved for the treatment of metastatic breast cancer for patients who have previously received trastuzumab and chemotherapy with either paclitaxel or docetaxel. T-DM1 is a combination of trastuzumab linked to very small amount of a strong chemotherapy. This allows the drug to deliver chemotherapy into the cancer cell while lessening the chemotherapy received by healthy cells. T-DM1 is given by vein every 3 weeks.
- Lapatinib (Tykerb). Women with HER2-positive metastatic breast cancer may benefit from lapatinib when trastuzumab and pertuzumab in combination with docetaxel are no longer effective at controlling the cancer’s growth. The combination of lapatinib and the chemotherapy capecitabine is approved to treat metastatic HER2-positive breast cancer when a patient has already received chemotherapy and trastuzumab. The combination of lapatinib and letrozole is also approved for metastatic HER2-positive and ER-positive cancer. Lapatinib is also used in combination with trastuzumab for patients whose cancer is growing while on trastuzumab. Lapatinib is also considered after treatment with T-DM1. Lapatinib may be able to enter into the brain, and could be an option for HER2-positive breast cancer that has spread to the brain.
Targeted therapy for metastatic hormone receptor-positive/HER2-negative breast cancer
- Palbociclib (Ibrance). This oral drug targets a protein in breast cancer cells called CDK4/6, which may stimulate cancer cell growth. Used along with the AI letrozole, the drug is an option for women who have been through menopause and have ER-positive, HER2-negative metastatic breast cancer. Palbociclib can also be used with fulvestrant if the cancer has worsened after receiving other hormonal therapy. Palbociclib generally has few side effects. It can lower the number of white blood cells. But it does not appear to increase the risk of serious infections that are linked to low numbers of white blood cells.
- Ribociclib (Kisqali). Like palbociclib, this oral drug targets a protein in breast cancer cells called CDK4/6, which may stimulate cancer cell growth. Used with an AI, this drug is an option for women who have been through menopause and have ER-positive, HER2-negative metastatic breast cancer. Side effects of ribociclib can include low numbers of white blood cells, increases in enzymes linked with liver damage, and changes in heart rhythms.
- Everolimus (Afinitor, Zortress). Everolimus is used with the AI exemestane for ER-positive, HER2-negative metastatic breast cancer that has grown despite treatment with another AI. Side effects of everolimus can include mouth sores, rash, diarrhea, and, rarely, an inflammation of the lungs called interstitial pneumonitis.
Radiation therapy
Radiation therapy is the use of high-energy x-rays or other particles to kill cancer cells. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist. The most common type of radiation treatment is called external-beam radiation therapy, which is radiation given from a machine outside the body. When radiation is given by placing radioactive sources into the tumor, it is called brachytherapy.
Radiation therapy may be used to shrink or slow tumor growth. It can also treat symptoms from the cancer, such as pain. Used by itself, or in combination with surgery, radiation therapy can also treat breast cancer that has spread to the brain. Several different types of radiation therapy can be used, including whole brain radiation, stereotactic radiosurgery, and fractionated stereotactic radiotherapy.
A radiation therapy regimen, or schedule, usually consists of a specific number of treatments given over a set period of time. Doctors will set the schedule and radiation dose for breast cancer metastases based on a patient’s individual medical needs and prior use of radiation therapy.
Radiation therapy can cause general side effects, such as fatigue and skin problems. In addition to general side effects, other side effects may occur and depend on the type of radiation therapy given and where on the body it is directed.
Learn more about the basics of radiation therapy.
Surgery
Surgery is the removal of a tumor and some surrounding healthy tissue during an operation. A surgical oncologist is a doctor who specializes in treating cancer with surgery. Surgery is not often used to treat metastatic breast cancer. However, doctors may recommend surgery to remove a tumor that is causing discomfort. Research continues on whether women who are first diagnosed with metastatic breast cancer live longer if the primary breast tumor is removed.
Surgery, used by itself or with radiation therapy, can be used to treat breast cancer that has spread to the brain. The goal is to shrink or temporarily get rid of the cancer in the brain.
Before surgery, talk with your health care team about the possible side effects from the specific surgery you will have. Learn more about the basics of cancer surgery.
