Chemotherapy for Breast Cancer

Overview
Chemotherapy is the treatment of cancer with drugs. Chemotherapy drugs may be taken intravenously or orally. Chemotherapy may be given after surgery (referred to as adjuvant chemotherapy), before surgery (neoadjuvant therapy), or in cases of advanced breast cancer. The goal of chemotherapy is to kill cancer cells, shrink tumors and prevent or slow the spread of cancer. Neoadjuvant chemotherapy can help to shrink tumors in order to conserve breast tissue and avoid mastectomy. Adjuvant chemotherapy can help kill any remaining cells left in your body after the tumors were removed. When breast cancer is advanced, chemotherapy can help slow the growth and spread of tumors and treat pain.

Chemotherapy is typically recommended when breast cancer has spread to the lymph nodes, and in cases where breast cancer is considered to be an especially aggressive type. It is not usually recommended for non-invasive, non-aggressive types of breast cancer.

There are many classes of chemotherapy drugs. Most chemotherapy drugs are given in combinations of two or more drugs of different classes depending on what stage of cancer you have, how effective they are in your specific case, and how well your body tolerates any side effects. If one combination is not showing results, or if you experience intense side effects, your doctor may adjust your dosage or change the combination of drugs you receive.

Classes of chemotherapy drugs used for breast cancer include anthracyclines, taxanes and platinum agents. Anthracyclines are believed to inhibit and damage the DNA of cancer cells, preventing tumors from growing. Taxanes seem to disrupt cell division, which also helps prevent the growth of tumors. Platinum agents are believed to link with cancer cell DNA, causing cell death and tumor shrinkage. Other common drugs used in chemotherapy include fluorouracil, or 5-FU, and Cytoxan. Fluorouracil, which has been used as a chemotherapy drug for more than 30 years, is believed to kill cancer cells by depriving them of a key molecule needed for metabolism. Cytoxan interferes with DNA replication in cancer cells and slows or prevents tumor growth. Some drugs, such as trastuzumab (Herceptin) and lapatinib (Tykerb), target certain kinds of tumors that produce specific proteins.

What does it involve?
Chemotherapy is administered in cycles of treatment and recovery. Cycles are usually two or four weeks long. Depending on which drugs you are receiving and how well you tolerate side effects, the drugs may be given only on the first day of the cycle, or as frequently as every day for 14 days. Each period of treatment will be followed by a recovery period to allow your body to rest. In some women with breast cancer, more frequent treatments and shorter recovery periods prove effective. This is called dose-dense chemotherapy. However, this type of chemotherapy may increase the intensity of side effects. For adjuvant and neoadjuvant chemotherapy, treatment usually lasts three to six months. Chemotherapy for advanced breast cancer may be given for longer.

Before you begin chemotherapy, it is a good idea to work on improving your overall health. Get plenty of rest; avoid stress; eat a healthy diet focused on whole grains, fresh vegetables and fruit; visit your dentist for a check-up and cleaning; and ask your doctor for a flu vaccine. These steps can help you cope with side effects and avoid infections during chemotherapy treatment.

Before chemotherapy treatment begins, your oncologist (doctor specializing in cancer) will review the results of all of your tests and scans and recommend chemotherapy regimens that will work for you. They will go over the benefits and side effects associated with each option. Once a regimen has been chosen, the oncologist will walk you through the treatment consent form and get your signature.

If you are taking chemotherapy drugs orally, you can do it at home. If you are taking chemotherapy drugs intravenously, you will usually need to receive them in a clinical setting such as a doctor’s office or cancer treatment center. You may receive them through a slow-drip infusion through a needle in your hand or arm, as an intramuscular (into the muscle) or subcutaneous (under the skin) injection, or you may receive a port placed in your chest or a catheter (thin, flexible tube) placed in your chest or arm. If you receive a port or a catheter, it will be placed during a brief outpatient surgery. The benefit of having a port or catheter is that you can receive chemotherapy and have blood taken through them without having the discomfort of a needle each time. If you also receive a portable pump, you may be able to receive intravenous chemotherapy at home. If you do have a port or catheter, monitor the skin around the device carefully for any sign of infection. After your chemotherapy treatments are finished, the device will be quickly and easily removed. For some regimens, you will receive some drugs intravenously and other drugs orally.

At your first chemotherapy appointment, the nurse or chemotherapy technician will check your vitals include pulse, temperature, blood pressure and respiration rate. Your weight will be taken in order to calculate the appropriate dose, and blood will be taken to obtain a complete blood count (CBC). Before the chemotherapy starts, you may receive intravenous fluids or medicine to help prevent nausea.

Each chemotherapy treatment can last one or several hours. To help pass the time, you can bring books, a laptop, knitting, materials for writing letters, puzzles, a board game and a friend, or anything else that you might enjoy. You can also take a nap.

After a chemotherapy session, the nurse or chemotherapy technician may check your vitals again to make sure you are stable after receiving the drugs. You may feel able to drive yourself home, but it might be easier to arrange a ride in advance. You may feel very fatigued and need to rest for a day or two after receiving chemotherapy. Be sure to drink plenty of fluids in order to avoid dehydration and constipation. Avoid beverages containing alcohol and caffeine, since these can make dehydration worse.

While you are undergoing chemotherapy treatment, your doctor may periodically order tests to check the effectiveness of the drug regimen and the severity of any side effects. These tests may include x-rays, magnetic resonance imaging (MRI) scans, computerized tomography (CT or CAT) scans, positron emission tomography (PET) scans, bone scans, and blood tests to find out blood cell counts and levels of tumor marker chemicals. The doctor may change your chemotherapy regimen based on the results of these tests.

Intended Outcomes
Chemotherapy can reduce the risk of early-stage breast cancer recurring after surgical treatment. It can also help women with advanced-stage metastatic breast cancer live longer.

Results
In a summary of 60 different clinical trials, adjuvant chemotherapy was shown to improve survival rates significantly at the end of 15 years. Women under age 50 showed the greatest increase in survival rates with chemotherapy. The summary was written in 2005, and last updated in 2014.

In other summary of several clinical trials involve 100 or more participants, neoadjuvant chemotherapy showed comparable results with adjuvant chemotherapy, and in many cases allowed women to conserve breast tissue and receive a lumpectomy instead of mastectomy. This summary was also updated in 2014.

A 2005 article summarizing current chemotherapy treatment regimens for advanced metastatic breast cancer indicated that some drug combinations can extend women’s lives by up to eight months, or 37 percent longer.

Constraints
Most chemotherapy drugs work against cells that divide and multiply very quickly. This makes them effective against cancer cells. However, healthy cells in certain parts of your body, including bone marrow, hair, and the lining of the digestive system, also divide rapidly. Therefore, many common side effects of chemotherapy are related to damage in these areas.

Each class of chemotherapy drugs causes different side effects, some of which are very serious. What side effects you experience will depend on many factors including which drug combination your doctor prescribes, your dosage, and how well your body can tolerate the treatment. If you cannot tolerate the side effects, your doctor will try decreasing dosage or changing the combination in an effort to minimize danger and discomfort. Always report side effects to your doctor. Some side effects, such as nausea, can be eased with other medicines.

Some of the most common side effects of chemotherapy include fatigue, nausea, vomiting, diarrhea, loss of appetite, weight loss, hair loss (alopecia) and mouth sores. Damage to bone marrow can cause low white blood cell count, weakened immune system, and bruising or bleeding due to fewer platelets, a blood component that causes clotting. Other side effects of chemotherapy can include shortness of breath, severe exhaustion, trouble swallowing, joint pain and skin changes such as nail discoloration and thin, brittle hair. Chemotherapy may also cause skin problems such as bruising or bleeding at the injection site, chest pain, fever and chills. Some women report having trouble with memory or concentration, commonly referred to as “chemo brain.”
All of these side effects usually disappear soon after the end of treatment, although fatigue may last for years after treatment is over.

Chemotherapy treatment also affects the reproductive system in many ways. Chemotherapy may cause changes in the menstrual cycle of young women, or bring on early menopause in older women. Early menopause may cause osteoporosis. Some drugs can also damage ovaries, which can lead to permanent infertility. Women who will be taking drugs that may cause infertility can choose to store fertilized eggs so that they can have children later. It is possible, but not safe, to become pregnant while receiving chemotherapy. Women who are still in their childbearing or premenopausal years should talk to their doctors about safe and effective birth control methods to use while on chemotherapy. If you are diagnosed with breast cancer while you are pregnant, you may be able to receive certain chemotherapy drugs during the second and third trimesters.

Some chemotherapy drugs can cause neuropathy, or damage to nerves. This may result in tingling in hands and feet, or even blisters and sores. These symptoms eventually go away after treatment is over.

One of the most serious side effects of some chemotherapy drugs includes cardiotoxicity, or damage to the heart. This damage can cause problems with heart rhythm (arrhythmia) or deterioration of the heart muscle (cardiomyopathy). These problems can surface at any time, even years after treatment.

In very rare cases, chemotherapy can make women susceptible to leukemia in the 10 years following treatment.

Many drugs can cause allergic reactions which, in the most serious cases, can result in death. Seek immediate medical help if you experience signs of a severe allergic reaction such as difficulty breathing or swelling in the face, throat, eyes, lips or tongue.

Many women also experience feelings of fear, sadness and depression while undergoing chemotherapy or while recovering after treatment has finished. In order to combat these feelings, you can join a support group made up of other women fighting breast cancer, see a therapist who can help you find ways to cope, or consider asking your doctor for antidepressant medication.

Out of pocket expenses for chemotherapy treatments average $2,000, but may cost more. Some women take extra time off from work to recover from chemotherapy, which may make it more difficult to keep their jobs. Some women may find it difficult to recover financially after receiving chemotherapy.