What is chemotherapy?
Chemotherapy treatment uses drugs to disrupt the cycles of cell production,and destroy or inhibit the growth of cancer cells. These are known as cytotoxic drugs (toxic to cells).
Chemotherapy can be used as adjuvant therapy ( following surgery to improve the chances of cure) or as palliative therapy ( given to reduce symptoms and extend life in the setting of advanced cancer.)
Unlike surgery and radiotherapy which are local treatments, this is systemic treatment, meaning cells throughout the whole body are treated as the drugs circulate via the bloodstream.
Chemotherapy targets cells which are actively dividing and growing. Other body cells including hair follicles, fingernails and toenails, cells in the digestive system and blood cells also divide frequently so acquire some damage from the treatment. However, they are generally able to repair themselves. Cancer cells are more likely to be destroyed by the treatment as they don’t have this repair mechanism.
Chemotherapy dosages and the timing of cycles are calculated to find a balance between inflicting maximum damage on cancer cells while minimising effects on healthy cells. Regular treatment cycles consist of drug administration followed by a period of rest and recovery. This enables the healthy cells to repair before the next cycle is given.
Learn more about chemotherapy side effects.
When chemotherapy is given after surgery it is called adjuvant treatment. The aim is to reduce the risk of cancer recurrence by destroying any microscopic cancer cells which may remain in the body after the tumour has been removed.
Neo- adjuvant chemotherapy
In certain cases such as inflammatory cancer, locally- advanced cancer and some highly proliferative types of cancer, chemotherapy can be administered before surgery to shrink the tumour in the breast and lymph nodes. It might also be given to downsize a large tumour to make breast conserving surgery an option rather than mastectomy. So far, clinical trials have not shown that giving neo-adjuvant chemotherapy increases or decreases overall survival as compared to adjuvant treatment however it may provide an early indication of response to treatment and present an opportunity for researching promising new treatments.
Neo-adjuvant chemotherapy also provides an opportunity to proceed with chemotherapy while awaiting more information, such as genetic test results, which might impact on surgery decisions.
Who needs chemotherapy?
Chemotherapy may be recommended when the pathology results indicate there is an increased risk that the cancer could recur in the future.
- The primary tumour was large
- The lymph nodes contained cancer cells
- The breast tumour was high grade or had other high risk features
- The tumour tested negative for hormone receptors, meaning it would not respond to hormone therapy.
- The tumour tested positive for the HER2 receptor, requiring treatment with chemotherapy and Herceptin.
- Your age and general health, and your personal preference are also considered when planning treatment.
How is chemotherapy given?
Different chemotherapy drugs are used depending on the type of breast cancer you have, and the state of your general health. Usually you will have a combination of drugs to increase the effectiveness of the treatment. Drugs may also be given sequentially.
Chemotherapy is generally given by intravenous infusion into a vein in the arm or hand in three weekly cycles, although some drugs are given weekly.
Some drugs have a greater potential to irritate the veins so an implantable port may be surgically inserted under the skin of the upper chest to give easy access to a major blood vessel. This reduces discomfort caused by frequent access and avoids damage to small veins. A fine tube runs from the port into a major blood vessel. Once in place the port can be easily accessed with a needle, enabling drugs to be administered and blood samples taken without too much discomfort. The port is seen as a bump under the skin and can be removed once treatment ends.
Treatment may last from 4-6 months or sometimes longer, depending on the combination of drugs used.
Your chemotherapy will be administered in the oncology day stay clinic so you will go home after each treatment. You will then have a period of rest and recovery at home before returning for your next cycle of treatment. A blood test will be taken to make sure your blood cells have recovered sufficiently before giving the next treatment.
These are some of the drugs used in breast cancer chemotherapy. Combinations of these are used to treat early and locally advanced cancer. Herceptin may be added for treatment of HER2 positive disease.
Ask your oncologist why a particular combination and schedule (regimen) has been recommended for you.
- docetaxel (Taxotere)
- paclitaxel (Taxol)
These drugs, known as Taxanes, belong to a class of chemotherapy drugs known as plant alkaloids, and were originally developed from the bark of the Pacific Yew tree. They are antimicrotubule drugs, which means they inhibit the microtubule structures which help the cancer cells divide and multiply. They’re given by infusion into a vein.
- doxorubicin (Adriamycin)
These drugs are antitumour antibiotics, originally developed from bacteria found in the soil. They block cell growth by interfering with DNA and are given by infusion into a vein.
These are known as an alkylating agents, and they target cancer cells in the resting phase of the cell cycle. They attach to DNA, preventing replication of the cancer cells, and are given by infusion into a vein.
- 5-fluorouracil (5FU)
- capecitabine (Xeloda) used to treat metastatic breast cancer. Taken orally.
Antimetabolites attack cells at very specific times during the cell cycle, preventing cell division. Capecitabine is a pro-drug which converts to fluorouracil in the tumour. With the exception of capecitabine, which is given orally, antimetabolites are given by infusion into a vein.
vinorelbine ( Navelbine)
Originally derived from the periwinkle plant. Inhibits the action of microtubules to stop breast cancer cells dividing and cause cell death. Used to treat metastatic breast cancer.
Chemotherapy affects people in different ways. Side effects vary depending on the type of drug given, the dosage, the frequency of treatment and the individual person receiving the treatment. Some people experience mild side effects, while for others they are more severe. Your oncologist will advise you of side effects which might be expected with your particular chemotherapy regimen.
Always discuss your side effects with your specialist team as often the symptoms can be controlled, making the treatment easier to tolerate. Be prepared to ask for help if you are feeling uncomfortable or finding the side effects difficult to cope with.
These usually occur early in the treatment and disappear after treatment has come to an end.
Hair loss (alopecia)
Hair loss, particularly on the scalp, is probably the most well-known side effect of breast cancer chemotherapy and one which can be very distressing for women. It usually occurs from 2 weeks after the first treatment and the hair may fall out gradually or more quickly, in clumps. Eyebrows, eyelashes, and hair in the underarms, pubic area and beard can also be variably affected. Generally the hair begins to grow back about 4-6 weeks after the last treatment.
The Ministry of Health provides a grant for women who want to wear a wig, and it is a good idea to pick this out before starting treatment to more easily match hair colour, style etc. Scarves and hats are also available and covered by the subsidy. Read more here Link to Wigs (Support tab)
Although hair loss on the scalp is the most obvious, hair is lost all over the body, including pubic hair and eyebrows.
Look Good Feel Better seminars help women with makeup, skincare and wig styling to boost self- esteem during treatment. There are also sessions which cater for men.
Scalp cooling with " cold caps" constricts blood vessels in the scalp and this is thought to restrict the uptake of chemotherapy drugs in the hair follicles, and reduce hair loss. A special cap containing a cooling substance which is chilled and maintained to a specific temperature, is worn immediately before, during, and for a period after each chemotherapy treatment. This is becoming available in some treatment units in the USA, UK and Australia but is not currently provided in NZ apart from a pilot study using a Paxman scalp cooling machine at Nelson Hospital. This is being funded by the Breast Cancer Foundation.
Scalp cooling doesn't eliminate hair loss but has been shown to reduce it and is most effective when used withTaxane therapy.
Read more about the Paxman system here.
Nausea, vomiting, diarrhoea
Some drugs can cause nausea and/or vomiting but this can usually be well controlled with anti-nausea medication. It’s important to keep in touch with your oncology team so that appropriate medications can be given to relieve symptoms.Its also important to let your oncologist know if you have a history of severe pregnancy- induced nausea or travel sickness.
It may help to have regular small meals rather than large ones, and it’s very important to maintain a good fluid intake. Ginger tea or ginger ale may help with mild nausea.
Avoid spicy or greasy foods or foods with strong odours if these contribute to nausea.
If you have persistent vomiting or diarrhoea you could become dehydrated, so it’s important to have an adequate fluid intake. Let your doctor know if the diarrhoea or vomiting is severe or persistent so that effective medications can be prescribed to remedy this.
Some chemotherapy drugs can cause nerve pain, or tingling and even numbness, particularly in the hands and feet. This is known as peripheral neuropathy. For most people this resolves after treatment but may sometimes persist for months, and occasionally becomes a long-term problem. Always tell your oncology team if this is happening to you during treatment.
Brittle fingernails and toenails
Some chemotherapy drugs, especially docetaxel and paclitaxel, may cause the nails to become brittle and pigmented, develop ridges, or fall off. It’s important to take care of the skin around the nails to avoid infection and it’s best to keep the nails short.The use of nail hardener/polish and immersing the fingertips in ice while having your treatment might might help to protect your fingernails.
Some people gain weight while having chemotherapy, and there are many reasons for this. The drugs themselves can cause metabolic changes, your lifestyle will probably be less active than usual, and you may be eating more as a way of keeping nausea at bay. If your chemotherapy puts you into early menopause, this might also cause you to gain weight.
Try and maintain a well-balanced diet during treatment as much as possible. Maintaining a healthy weight after treatment for breast cancer helps decrease the risk of breast cancer recurrence in post-menopausal women.
Simple exercise such as walking for 45 minutes, 3 times a week , at a pace which increases your heart rate can also be helpful in maintaining a healthy weight and may help you to cope with some of the side effects of chemotherapy.
Some chemotherapy drugs can cause a drop in white blood cells (neutropenia) which limits the body’s ability to fight infection. This commonly happens about 10-14 days after each cycle although the effect may be earlier with certain drugs.( e.g. 5-9 days with docetaxel) You will be advised about this and will be monitored with regular blood tests.
You will be given specific instructions about monitoring your temperature. If it rises to or above 38 degrees Celsius,or remains persistently above 37.5 degrees this could indicate a serious infection (febrile neutropenia). You will need to notify the oncology team urgently, as you may need to be admitted to hospital for urgent treatment with antibiotics. Your next dose of chemotherapy may need to be delayed or a lower dosage may be prescribed. With some regimens, injections of white blood cell growth factors may be given to maintain an adequate cell count. You should also notify your oncology team if you feel unwell, with chills and shakes, even in the absence of a high temperature.
Some drugs may affect the red blood cells, causing anaemia, or affect the platelets. Platelets help blood to clot, so lowered levels may cause bruising, nosebleeds etc. These levels will be closely monitored during treatment to avoid problems.
Sore mouth or ulcers
Some drugs cause inflammation and ulceration of the lining of the mouth, known as mucositis. Mouthwashes, gentle teeth cleaning with a soft brush, regular use of lip balm and drinking plenty of fluids may help. Try to avoid painful stimuli such as hot food and drinks, spicy food, smoking and alcohol.
Longer term side effects
Tiredness is commonly reported during treatment. This may be a direct effect of the drugs or may be due to other factors such as disrupted sleep patterns.
Try to get adequate rest but also try to get some exercise such as a walk outside each day as this can actually give you more energy. Let others help when your energy levels are low.
Usually energy levels recover after treatment finishes but this commonly takes time. In some cases full recovery may take 12 months or more.
Some people notice they are having concentration and short-term memory problems following their chemotherapy. This is often referred to as “chemo brain”. The severity and duration of symptoms differ from person to person. For some people the symptoms are very mild and resolve soon after treatment stops, but others may find their daily life is noticeably affected for a much longer period, restricting their ability to return to work in their pre-treatment capacity.
- It’s not really clear what causes “chemo- brain” so there is no proven treatment, but the following strategies may help:
- Try to get enough sleep. Fatigue usually makes the “chemo- brain” worse.
- Reduce stress as much as possible. Yoga, meditation, relaxation techniques may help
- Keep track of appointments, family and work schedules, using “to do” lists in a diary or on your smart phone.
- Exercise. Regular movement reduces fatigue and makes you feel more alert.
- Eat a healthy, well balanced diet and restrict alcohol
In younger women who are still having periods, chemotherapy effectively shuts down ovarian function, stopping oestrogen production. This mechanism can lower the recurrence risk in young women whose cancers rely on oestrogen to grow. Unfortunately, it may cause early menopause and loss of fertility in some young women. However, not all young women become infertile with chemotherapy. Many women recover ovarian function and their periods will return within a year. Even if the periods don’t return some women will still be fertile.
Read more about preserving fertility
The older you are and the closer to a natural menopause, the less likely it is that your ovarian function will recover. Having chemotherapy over the age of 40 increases the risk of early menopause. Because the onset is more sudden than a natural menopause, symptoms such as hot flushes and vaginal dryness can be more severe initially. Menopause also causes a reduction in bone density. Talk to your oncologist about ways to maintain bone health and manage your symptoms.
Some chemotherapy drugs such as doxorubicin, epirubicin and biological therapies such as trastuzumab are known to increase the risk of heart problems. Although the risk is small,your heart health will be assessed before starting treatment and continue to be monitored during treatment. It’s important to continue to take steps to keep your heart in good health:
- Don't smoke
- Keep blood pressure and cholesterol levels in a healthy range
- Exercise regularly
- Eat a well-balanced diet to maintain a healthy weight.