Chemotherapy (chemo) uses anti-cancer drugs that may be given intravenously (injected into your vein) or by mouth. The drugs travel through the bloodstream to reach cancer cells in most parts of the body. Sometimes, if cancer spreads to the spinal fluid, which surrounds and cushions the brain and spinal cord, chemo may be given directly into in this area (called intrathecal chemotherapy).
Not all women with breast cancer will need chemo, but there are several situations in which chemo may be recommended.
Adjuvant chemo might be given to try to kill any cancer cells that might have been left behind or have spread but can't be seen, even on imaging tests. These cells are considered microscopic because they can’t be seen by the naked eye. If these cells were allowed to grow, they could form new tumors in other places in the body. Adjuvant chemo can lower the risk of breast cancer coming back. Sometimes it is not clear if chemotherapy will be helpful. There are tests available, such as Oncotype DX, that can help determine which women will most likely benefit from chemo after breast surgery. See Breast Cancer Gene Expression Tests for more information.
Neoadjuvant chemo might be given to try to shrink the tumor so it can be removed with less extensive surgery. Because of this, neoadjuvant chemo is often used to treat cancers that are too big to be removed by surgery when first diagnosed, have many lymph nodes involved with cancer, or are inflammatory breast cancers .
If after neoadjuvant chemo, cancer cells are still found when surgery is done (also called residual disease), you might be offered more chemotherapy (adjuvant chemotherapy) to reduce the chances of the cancer coming back (recurrence).
Some other reasons you might get neoadjuvant chemo:
Keep in mind that not all women with breast cancer are good candidates for neoadjuvant chemo.
Chemo can be used as the main treatment for women whose cancer has spread outside the breast and underarm area to distant organs like the liver or lungs. Chemo can be given either when breast cancer is diagnosed or after initial treatments. The length of treatment depends on how well the chemo is working and how well you tolerate it.
In most cases, chemo has the greatest effect when more than one drug is used at a time. Often, combinations of 2 or 3 drugs are used. Doctors use many different combinations, and it's not clear that any particular drug combination is the best.
Although drug combinations are often used to treat early breast cancer, advanced breast cancer often is treated with single chemo drugs. Still, some combinations, such as paclitaxel plus gemcitabine, are commonly used to treat metastatic breast cancer.
Chemo drugs for breast cancer are typically given into a vein (IV), either as an injection over a few minutes or as an infusion over a longer period of time. This can be done in a doctor’s office, infusion center, or in a hospital setting.
Often, a slightly larger and sturdier IV is required in the vein system to administer chemo. These are known as central venous catheters (CVCs), central venous access devices (CVADs), or central lines. They are used to put medicines, blood products, nutrients, or fluids right into your blood. They can also be used to take out blood for testing.
There are many different kinds of CVCs. The most common types are the port and the PICC line. For breast cancer patients, the central line is typically placed on the side opposite of the breast cancer. If a woman has breast cancer in both breasts, the central line will most likely be placed on the side that had fewer lymph nodes removed or involved with cancer.
Chemo is given in cycles, followed by a rest period to give you time to recover from the effects of the drugs. Chemo cycles are most often 2 or 3 weeks long. The schedule varies depending on the drugs used. For example, with some drugs, chemo is given only on the first day of the cycle. With others, it is given one day a week for a few weeks or every other week. Then, at the end of the cycle, the chemo schedule repeats to start the next cycle.
Adjuvant and neoadjuvant chemo is often given for a total of 3 to 6 months, depending on the drugs used. The length of treatment for metastatic (Stage 4) breast cancer depends on how well it is working and what side effects you have.
Doctors have found that giving the cycles of certain chemo drugs closer together can lower the chance that the cancer will come back and improve survival for some women with breast cancer. For example, a drug that would normally be given every 3 weeks might be given every 2 weeks. This can be done for both neoadjuvant and adjuvant treatment. It can lead to more problems with low blood cell counts, so it’s not an option for all women. For example, a chemo combination sometimes given this way is doxorubicin (Adriamycin) and cyclophosphamide (Cytoxan) every 2 weeks, followed by paclitaxel (Taxol) every 2 weeks.
Chemo drugs can cause side effects, depending on the type and dose of drugs given, and the length of treatment. Some of the most common possible side effects include:
Chemo can also affect the blood-forming cells of the bone marrow, which can lead to:
These side effects usually go away after treatment is finished. There are often ways to lessen these side effects. For example, drugs can be given to help prevent or reduce nausea and vomiting.
Other side effects are also possible. Some of these are more common with certain chemo drugs. Ask your cancer care team about the possible side effects of the specific drugs you are getting.
For younger women, changes in menstrual periods are a common side effect of chemo. Premature menopause (not having any more menstrual periods) and infertility (not being able to become pregnant) may occur and could be permanent. If this happens, there is an increased risk of heart disease, bone loss, and osteoporosis. There are medicines that can treat or help prevent bone loss.
Even if your periods stop while you are on chemo, you may still be able to get pregnant. Getting pregnant while on chemo could lead to birth defects and interfere with treatment. If you have not gone through menopause before treatment and are sexually active, it’s important to discuss using birth control with your doctor. It is not a good idea for women with hormone receptor-positive breast cancer to take hormonal birth control (like birth control pills), so it’s important to talk with both your oncologist and your gynecologist (or family doctor) about what options would be best for you. When women have finished treatment (like chemo), they can safely go on to have children, but it's not safe to get pregnant while being treated.
If you think you might want to have children after being treated for breast cancer, talk with your doctor soon after being diagnosed and before you start treatment. For some women, adding medicines, like monthly injections with a luteinizing hormone-releasing hormone (LHRH) analog, along with chemo, can help them have a successful pregnancy after cancer treatment. To learn more, see Female Fertility and Cancer.
If you are pregnant when you get breast cancer, you still can be treated. Certain chemo drugs can be taken safely during the last 2 trimesters of pregnancy. More details can be found in Treating Breast Cancer During Pregnancy.
Even though it is not common, doxorubicin, epirubicin, and some other chemo drugs can cause permanent heart damage (called cardiomyopathy). The risk is highest if the drug is used for a long time or in high doses. Damage from these drugs also happens more often if other drugs that can cause heart damage (such as those that target HER2) are used. Other heart failure risk factors, such as family history of heart problems, high blood pressure, and diabetes can also put you at risk if you receive one of these drugs.
Most doctors will check your heart function with a test like an echocardiogram (an ultrasound of the heart; also called an ECHO) or a MUGA scan before starting one of these drugs. They also carefully control the doses, watch for symptoms of heart problems, and may regularly repeat heart tests during treatment. If the heart function begins to worsen, treatment with these drugs will be temporarily or permanently stopped. Still, in some people, signs of damage might not appear until months or years after treatment stops.
Many drugs used to treat breast cancer, including taxanes (docetaxel, paclitaxel, and protein-bound paclitaxel), platinum agents (carboplatin, cisplatin), vinorelbine, eribulin, and ixabepilone, can damage nerves in the hands, arms, feet, and legs. This can sometimes lead to symptoms in those areas like numbness, pain, burning or tingling sensations, sensitivity to cold or heat, or weakness. In most cases these symptoms go away once treatment is stopped, but in some women it might last a long time or may become permanent. There are medicines that could help with these symptoms.
Certain chemo drugs, such as capecitabine (Xeloda) and liposomal doxorubicin (Doxil), can irritate the palms of the hands and the soles of the feet. This is called hand-foot syndrome. Early symptoms include numbness, tingling, and redness. If it gets worse, the hands and feet can become swollen and uncomfortable or even painful. The skin may blister, leading to peeling or even open sores. There is no specific treatment, although some creams or steroids given before chemo may help. These symptoms gradually get better when the drug is stopped or the dose is lowered. The best way to prevent severe hand-foot syndrome is to tell your doctor when symptoms first come up, so that the drug dose can be changed or other medicines can be given.
Many women who are treated with chemotherapy for breast cancer report a slight decrease in mental functioning. They may have some problems with concentration and memory, which may last a long time. Although many women have linked this to chemo, it also has been seen in women who did not get chemo as part of their treatment. Still, most women function well after treatment. In studies that have found chemo brain to be a side effect of treatment, the symptoms most often last for a few years.
Very rarely, certain chemo drugs, such as doxorubicin (Adriamycin), can cause diseases of the bone marrow, such as myelodysplastic syndromes or even acute myeloid leukemia, a cancer of white blood cells. If this happens, it is usually within 10 years after treatment. For most women, the benefits of chemo in helping prevent breast cancer from coming back or in extending life are far likely to exceed the risk of this rare but serious complication.
Many women do not feel as healthy after chemo as they did before. There is often a residual feeling of body pain or achiness and a mild loss of physical functioning. These changes may be very subtle and happen slowly over time.
Fatigue is another common problem for women who have received chemo. This may last a few months up to several years. It can often be helped, so it’s important to let your doctor or nurse know about it. Exercise, naps, and conserving energy may be recommended. If you have sleep problems, they can be treated. Sometimes fatigue can be a sign of depression, which may be helped by counseling and/or medicines.
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Last Revised: October 27, 2021