- How is breast cancer treated?
- Surgery for breast cancer
- Breast-conserving surgery (lumpectomy)
- Lymph node surgery for breast cancer
- Radiation therapy for breast cancer
- Chemotherapy for breast cancer
- Hormone therapy for breast cancer
- Targeted therapy for breast cancer
- Treatment of lobular carcinoma in situ
- Treatment of ductal carcinoma in situ
- Treatment of invasive breast cancer, by stage
- Treatment of breast cancer during pregnancy
Treatment of invasive breast cancer, by stage
The stage (extent) of your breast cancer is an important factor in making decisions about your treatment. In general, the more the breast cancer has spread, the more treatment you will likely need. But other information about your breast cancer can also affect your treatment options, as can your personal preferences.
The stage (extent) of a breast cancer is an important factor in determining the best treatment options. But other factors can also be important, such as:
- If the cancer cells contain hormone receptors (that is, if the cancer is ER-positive or PR-positive)
- If the cancer cells have large amounts of the HER2 protein (that is, if the cancer is HER2-positive)
- A woman’s overall health and personal preferences
Talk with your doctor about how these factors can affect your treatment options.
These breast cancers are still relatively small and either have not spread to the lymph nodes or have a tiny area of cancer spread in the sentinel lymph node (the first lymph node to which cancer is likely to spread).
Surgery is the main treatment for stage I breast cancer. These cancers can be treated with either breast-conserving surgery (BCS; sometimes called lumpectomy or partial mastectomy) or mastectomy. The nearby lymph nodes will also need to be checked, either with a sentinel lymph node biopsy (SLNB) or an axillary lymph node dissection (ALND).
In some cases, breast reconstruction can be done during the surgery to remove the cancer. But if you will need radiation therapy after surgery, it is often better to wait to get reconstruction until after the radiation is complete.
If mastectomy is done, radiation therapy is not usually needed. If BCS is done, radiation therapy is usually given after surgery to lower the chance of the cancer coming back in the breast. Women who are at least 70 years old may consider BCS without radiation therapy if ALL of the following are true:
- The tumor was 2 cm (a little less than 1 inch) or less across and it has been removed completely.
- The tumor contains hormone receptors and hormone therapy is given.
- None of the lymph nodes removed contained cancer.
Radiation after BCS still lowers the chance of the cancer coming back in women who meet these criteria, but it has not been shown to help them live longer.
Some women who do not meet these criteria may be tempted to avoid radiation, but studies have shown that not getting radiation increases the chances of the cancer coming back and can shorten their lives.
Adjuvant systemic therapy (chemo and other drugs)
For women who have a hormone receptor-positive (ER-positive or PR-positive) breast cancer, most doctors will recommend hormone therapy (tamoxifen or an aromatase inhibitor, or one followed by the other) as an adjuvant (additional) treatment, no matter how small the tumor is. Women with tumors larger than 0.5 cm (about ¼ inch) across may be more likely to benefit from it. Hormone therapy is typically given for at least 5 years.
If the tumor is smaller than 1 cm (about ½ inch) across, adjuvant chemotherapy (chemo) is not usually needed. Some doctors may suggest chemo if a cancer smaller than 1 cm has any unfavorable features (such as being high-grade, hormone receptor-negative, HER2-positive, or having a high score on a gene panel such as Oncotype Dx). Adjuvant chemo is usually recommended for larger tumors.
For HER2-positive cancers, a year of adjuvant trastuzumab (Herceptin) is usually recommended as well.
For more information on adjuvant therapy, see “Drug treatment for stages I to III breast cancer.”
These breast cancers are larger than stage I cancers and/or have spread to a few nearby lymph nodes.
Local therapy (surgery and radiation therapy)
Stage II cancers are treated with either breast-conserving surgery (BCS; sometimes called lumpectomy or partial mastectomy) or mastectomy. The nearby lymph nodes will also need to be checked, either with a sentinel lymph node biopsy (SLNB) or an axillary lymph node dissection (ALND). Women who have BCS, or who have a large tumor (more than 5 cm or about 2 inches across) or cancer cells in the lymph nodes, are treated with radiation therapy after surgery. If chemotherapy is also needed after surgery, the radiation is delayed until the chemo is done.
In some cases, breast reconstruction can be done during the surgery to remove the cancer. But if you will need radiation after surgery, it is often better to wait to get reconstruction until after the radiation is complete.
Neoadjuvant and adjuvant systemic therapy (chemo and other drugs)
Systemic therapy is recommended for women with stage II breast cancer. Some systemic therapies are given before surgery (neoadjuvant therapy), and others are given after surgery (adjuvant therapy). Neoadjuvant treatments are often a good option for women with large tumors, because they can shrink the tumor before surgery, possibly enough to make BCS an option. But this doesn’t improve survival more than getting the drugs after surgery. In some cases, systemic therapy will be started before surgery and then continued after surgery.
The drugs used will depend on the woman’s age and the tumor’s hormone-receptor status and HER2 status. They may include:
- Chemotherapy: Chemo can be given before or after surgery.
- HER2 targeted drugs: If the cancer is HER2-positive, HER2 targeted drugs are started along with chemo. Both trastuzumab (Herceptin) and pertuzumab (Perjeta) may be used as a part of neoadjuvant treatment. Then trastuzumab is continued after surgery for a total of one year of treatment.
- Hormone therapy: If the cancer is hormone receptor-positive, hormone therapy (tamoxifen, an aromatase inhibitor, or one followed by the other) is typically used. It can be started before surgery, but because it continues for at least 5 years, it needs to be given after surgery as well.
For more information on adjuvant and neoadjuvant therapy, see “Drug treatment for stages I to III breast cancer.”
In stage III breast cancer, the tumor is large (more than 5 cm or about 2 inches across) or growing into nearby tissues (the skin over the breast or the muscle underneath), or the cancer has spread to many nearby lymph nodes.
If you have inflammatory breast cancer: Stage III cancers also include some inflammatory breast cancers that have not spread beyond nearby lymph nodes. Treatment of these cancers can be slightly different from the treatment of other stage III breast cancers. See Inflammatory Breast Cancer for details.
There are two main approaches to treating stage III breast cancer:
Starting with neoadjuvant therapy
Most often, these cancers are treated with neoadjuvant chemotherapy (before surgery). For HER2-positive tumors, the targeted drug trastuzumab (Herceptin) is given as well, sometimes along with pertuzumab (Perjeta). This may shrink the tumor enough to allow a woman to have breast-conserving surgery (BCS). If the tumor doesn’t shrink enough, a mastectomy is done. Nearby lymph nodes will also need to be checked. A sentinel lymph node biopsy (SLNB) is often not an option for stage III cancers, so an axillary lymph node dissection (ALND) is usually done.
Often, radiation therapy is needed after surgery. If breast reconstruction is done, it is usually delayed until after radiation is complete. In some cases, additional (adjuvant) chemo is given after surgery as well. Women with HER2-positive cancers receive trastuzumab after surgery to complete a year of treatment. Women with hormone receptor-positive (ER-positive or PR-positive) breast cancers will get adjuvant hormone therapy.
Starting with surgery
Another option for stage III cancers is to treat with surgery first. Because these tumors are fairly large and/or have grown into nearby tissues, this usually means getting a mastectomy. For women with fairly large breasts, BCS may be an option if the cancer hasn’t grown into nearby tissues. SLNB may be an option for some patients, but most will need an ALND. Surgery is usually followed by adjuvant systemic chemotherapy, and/or hormone therapy, and/or trastuzumab. Radiation is recommended after surgery.
For more information on adjuvant and neoadjuvant therapy, see “Drug treatment for stages I to III breast cancer.”
Drug treatment for stages I to III breast cancer
Most women with breast cancer in stages I to III will get some kind of drug therapy as part of their treatment. This may include:
- Hormone therapy (tamoxifen, an aromatase inhibitor, or one followed by the other)
- HER2 targeted drugs, such as trastuzumab (Herceptin) and pertuzumab (Perjeta)
- Some combination of these
The types of drugs that might work best depend on the tumor’s hormone receptor status, HER2 status, and other factors.
When is chemotherapy (chemo) used?
Chemo is usually recommended for all women with an invasive breast cancer whose tumor is hormone receptor-negative (ER-negative and PR-negative). It’s also typically recommended for women with hormone receptor-positive tumors who might benefit from getting chemo along with their hormone therapy, based on the stage and characteristics of their tumor.
Chemo, given either before surgery (neoadjuvant chemo) or after surgery (adjuvant chemo), can lower the risk of the cancer coming back, but it doesn’t remove the risk entirely. Before deciding if it’s right for you, talk to your doctor to make sure you understand the chance of your cancer returning both with or without getting chemo.
If you will be getting chemo, your doctor should discuss what specific drug regimens are best for you based on your cancer, its stage, your other health issues, and your preferences. The length of treatment usually ranges from 3 to 6 months.
When is hormone therapy used?
Hormone therapy is recommended for all women with hormone receptor-positive (ER-positive or PR-positive) invasive breast cancer, regardless of the size of the tumor or the number of lymph nodes with cancer cells. Hormone therapy is not likely to be effective for women with hormone receptor-negative tumors.
For post-menopausal women: Women who have gone through menopause and who have hormone receptor-positive tumors will generally get adjuvant hormone therapy. This might consist of:
- An aromatase inhibitor, such as anastrozole (Arimidex), letrozole (Femara), or exemestane (Aromasin) for 5 years
- Tamoxifen for 2 to 5 years followed by an aromatase inhibitor for 3 to 5 more years
- Tamoxifen for 5 to 10 years (for women who can't take aromatase inhibitors)
Chemotherapy can sometimes slow or stop ovarian function for a time. Women who stopped having periods during or after chemo may need their hormone levels tested to check to see if they are truly in menopause. Many women whose periods stopped from chemo have not truly gone through menopause, and their periods will return.
For pre-menopausal women: For women who haven’t gone through menopause, the most common treatment is tamoxifen, which is taken for 5 to 10 years. Aromatase inhibitors don’t help if the ovaries are still making estrogen, so they are not usually given to pre-menopausal women.
Some doctors also give a drug called a luteinizing hormone-releasing hormone (LHRH) analog, which temporarily stops the ovaries from functioning. Another (permanent) option is surgical removal of the ovaries (oophorectomy). Still, it’s not clear that removing the ovaries or stopping them from working helps tamoxifen work better for cancers that have been removed completely, so these treatments are not standard.
If you go through menopause during tamoxifen treatment (either naturally or because your ovaries are removed), you may be switched from tamoxifen to an aromatase inhibitor. Still, women may stop having periods on tamoxifen without truly going through menopause, so blood tests of hormone levels are often needed to see if you are in menopause and can benefit from aromatase inhibitors. Women who had their uterus removed (a hysterectomy) but still have their ovaries may need to have blood tests to check hormone levels to see if they have gone through menopause before taking an aromatase inhibitor.
Another option for pre-menopausal women (instead of tamoxifen), is taking an LHRH analog to turn off the ovaries along with an aromatase inhibitor.
Hormone therapy and chemotherapy: Hormone therapy might be started right away if you are not getting chemo. But getting hormone therapy and chemo together can make the chemo less effective, so hormone therapy is usually not started until after chemo is completed.
When are HER2 targeted drugs used?
Women who have HER2-positive cancers are usually given trastuzumab (Herceptin) along with chemo as part of their treatment. If the treatment is given before surgery (called neoadjuvant therapy), pertuzumab (Perjeta) may be given as well. After the chemo is finished, the trastuzumab is continued to complete a year of treatment.
Because these drugs can lead to heart problems, heart function is watched closely during treatment with tests such as echocardiograms or MUGA scans.
Online tools to help make decisions
To help decide if adjuvant therapy is right for you, you might want to visit the Mayo Clinic website at www.mayoclinic.com and type "adjuvant therapy for breast cancer" into the search box. You will find a page that will help you to understand the possible benefits and limits of adjuvant therapy.
Other online guides, such as www.adjuvantonline.com, are designed to be used by health care professionals. This website provides information about your risk of the cancer returning within the next 10 years and what benefits you might expect from hormone therapy and/or chemotherapy. You may want to ask your doctor if he or she uses this site.
Stage IV cancers have spread beyond the breast and nearby lymph nodes to other parts of the body. When breast cancer spreads, it most commonly goes to the bones, liver, and lungs. As the cancer progresses, it may also spread to the brain or other organs.
For women with stage IV breast cancer, systemic (drug) therapies are the main treatments. These may include:
- Hormone therapy
- Chemotherapy (chemo)
- Targeted drugs, such as trastuzumab (Herceptin) and pertuzumab (Perjeta)
- Some combination of these
Less often, surgery and/or radiation therapy may be useful in certain situations (see below).
Treatment can often shrink tumors, improve symptoms, and help women live longer. But in general, these cancers are very hard to cure.
Systemic (drug) treatments for stage IV breast cancer
The types of drugs used for stage IV breast cancer depend on the hormone receptor status and the HER2 status of the cancer:
- Hormone receptor-positive cancers: Women with hormone receptor-positive (ER-positive or PR-positive) cancers are often treated first with hormone therapy (tamoxifen or an aromatase inhibitor). Women who are post-menopausal may be treated first with palbociclib (Ibrance) along with a hormone drug like letrozole (Femara). Women who haven’t yet gone through menopause are often treated first with tamoxifen. But because hormone therapy can take months to work, chemo is often the first treatment for patients with serious problems from their cancer spread, such as problems breathing.
- Hormone receptor-negative cancers: Chemo is the main treatment for women with hormone receptor-negative (ER-negative and PR-negative) cancers, because hormone therapy isn’t helpful for these cancers.
- HER2-positive cancers: Trastuzumab (Herceptin) may help women with HER2-positive cancers live longer if it’s given with the first chemo for stage IV disease. Trastuzumab can also be given with the hormone therapy drug letrozole. Other options include ado-trastuzumab emtansine (Kadcyla) or pertuzumab (Perjeta) with chemo and trastuzumab. Treatment with ado-trastuzumab emtansine continues until the cancer starts growing again. It is not clear how long treatment with trastuzumab (with or without pertuzumab) should continue.
Local or regional treatments for stage IV breast cancer
Although systemic drugs are the main treatment for stage IV breast cancer, local and regional treatments such as surgery, radiation therapy, or regional chemotherapy are sometimes used as well. These can help treat breast cancer in a specific part of the body, but they are very unlikely to get rid of all of the cancer. These treatments are more likely to be used to help prevent or treat symptoms or complications from the cancer.
Radiation therapy and/or surgery may also be used in certain situations, such as:
- When the breast tumor is causing an open wound in the breast (or chest)
- To treat a small number of metastases in a certain area, such as the brain
- To help prevent bone fractures
- When an area of cancer spread is pressing on the spinal cord
- To treat a blood vessel blockage in the liver
- To provide relief of pain or other symptoms
In some cases, regional chemo (where drugs are delivered directly into a certain area, such as into the fluid around the brain or into the liver) may be useful as well.
If your doctor recommends such local or regional treatments, it is important that you understand their goal—whether it is to try to cure the cancer or to prevent or treat symptoms.
Relieving symptoms of advanced breast cancer
Treatment to relieve symptoms depends on where the cancer has spread. For example, pain from bone metastases may be treated with radiation therapy and/or drugs called bisphosphonates such as pamidronate (Aredia) or zoledronic acid (Zometa). Most doctors recommend bisphosphonates or the drug denosumab (Xgeva), along with calcium and vitamin D, for all patients whose breast cancer has spread to their bones. For more information about treatment of bone metastases, see Bone Metastasis.
Advanced cancer that progresses during treatment
Treatment for advanced breast cancer can often shrink the cancer or slow its growth (often for many years), but after a time, it tends to stop working. Further treatment options at this point depend on several factors, including previous treatments, where the cancer is located, and a woman's age, general health, and desire to continue getting treatment.
Progression while on hormone therapy
For hormone receptor-positive (ER-positive or PR-positive) cancers that were being treated with hormone therapy, switching to another type of hormone therapy sometimes helps. For example, if either letrozole (Femara) or anastrozole (Arimidex) were given, using everolimus (Afinitor) with exemestane may be an option. If the cancer is no longer responding to any hormone drugs, chemotherapy is usually the next step.
Progression while on chemotherapy
If the cancer is no longer responding to one chemo regimen, trying another may be helpful. Many different drugs and combinations can be used to treat breast cancer. However, each time a cancer progresses during treatment, it becomes less likely that further treatment will have an effect.
Progression while getting HER2 drugs
HER2-positive cancers that no longer respond to trastuzumab (Herceptin) might respond to lapatinib (Tykerb), another drug that attacks the HER2 protein. This drug is often given along with the chemo drug capecitabine (Xeloda), but it can be used with other chemo drugs, with trastuzumab, or even alone (without chemo). Other options for women with HER2-positive cancers include pertuzumab (Perjeta) with chemo and trastuzumab, or ado-trastuzumab emtansine (Kadcyla).
Because current treatments are very unlikely to cure advanced breast cancer, if you are in otherwise good health, you may want to think about taking part in a clinical trial testing a newer promising treatment.
Recurrent breast cancer
For some women, breast cancer may come back after treatment – sometimes years later. This is called a recurrence. Recurrence can be local (in the same breast or in the mastectomy scar), regional (in nearby lymph nodes), or in a distant area. Cancer that is found in the opposite breast is not a recurrence—it is a new cancer that requires its own treatment.
Treating local recurrence
For women whose breast cancer has recurred locally, treatment depends on their initial treatment. If you had breast-conserving surgery, a local recurrence in the breast is usually treated with mastectomy. If the initial treatment was mastectomy, recurrence near the mastectomy site is treated by removing the tumor whenever possible. This is followed by radiation therapy, but only if none had been given after the original surgery. (Radiation usually can’t be given to the same area twice.) In either case, hormone therapy, targeted therapy (like trastuzumab), chemotherapy, or some combination of these may be used after surgery and/or radiation therapy.
Treating regional recurrence
When breast cancer comes back in nearby lymph nodes (such as those under the arm or around the collar bone), it is treated by removing those lymph nodes. This may be followed by radiation aimed at the area. Systemic treatment (such as chemo, targeted therapy, or hormone therapy) may be considered after the local treatment as well.
Treating distant recurrence
In general, women whose breast cancer comes back in other organs, such as the bones, lungs, or brain, are treated the same way as those found to have stage IV breast cancer in these organs when they were first diagnosed (see treatment for stage IV). The only difference is that treatment may be affected by previous treatments a woman has had.
Recurrent breast cancer can sometimes be hard to treat. If you are in otherwise good health, you may want to think about taking part in a clinical trial testing a newer promising treatment.
See the Cancer Recurrence section for more information.
Last Medical Review: 09/25/2014
Last Revised: 05/04/2016