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 relieve symptoms and prolong survival 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 all rapidly dividing cells, and this includes cancer cells that 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 they also 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?
Each patient's treatment plan is individualised and many factors are considered when deciding whether to treat breast cancer with chemotherapy:
- the histology of the tumour
- the hormone receptor status
- the stage and grade of the tumour
- the presence of high risk indicators such as lymphovascular invasion
- recurrence score results from genomic profiling if available
- the patient's age and state of general health.
Your medical oncology team will advise you of the benefits versus risks of chemotherapy in your situation.
How is chemotherapy given?
Different chemotherapy drugs are used depending on the characteristics of your particular breast cancer, 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.This may be given into a vein in the arm or hand or administered via an implantable port inserted under the skin of the upper chest, gaining easy access to a major blood vessel. This reduces discomfort caused by frequent access and avoids damage to small veins. 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 can be seen as a bump under the skin and can be removed once treatment ends.
Chemotherapy drugs are commonly given in three-weekly cycles, although some drugs are given weekly. There are also some drugs that are given orally.
Adjuvant chemotherapy treatment may last from four to six 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 that 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.
Webinar: Managing chemo and radiation side effects
In this webinar, we discuss strategies and tips on how to manage the side effects of chemotherapy and radiation, to help boost your quality of life during this time.
Chemotherapy affects people in different ways. Side effects vary depending on the type of drug given, the dosage, the frequency of treatment and the general health of the 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 any side effects with your specialist team as often the symptoms can be relieved, making the treatment easier to tolerate. Be prepared to ask for help if you are feeling uncomfortable or finding any 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 that can be very distressing for women. It usually occurs from two 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 area can also be variably affected. Generally the hair begins to grow back about four to six weeks after the last treatment.This new growth is usually quite fine and may initially be curly.
- Bimatoprost 0.03% eye drops can be used to prevent eyelash loss caused by chemotherapy. It can stimulate eyelash growth and darkening of the lashes. Discuss this with your oncologist to see if it is appropriate for you.
- 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 are covered by the subsidy. Read more at Wigs and Headware
- It's important to apply sunscreen if you're outside and not wearing a wig, scarf or hat to cover your scalp .
- Look Good Feel Better seminars help women with makeup, skincare and wig styling to boost self- esteem during treatment. There are also sessions that 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 not generally provided in NZ hospitals, apart from a pilot study using a scalp cooling machine at Nelson Hospital, that is being funded by the Breast Cancer Foundation. Scalp cooling is offered in some private clinics.
Scalp cooling doesn't eliminate hair loss but has been shown to reduce it and is most effective when used with non-anthracycline regimens such as TC - docetaxel (Taxotere) and cyclophosphamide.
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
- It's 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. Tell your oncology team if the diarrhoea or vomiting is severe or persistent.
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.
- 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 causes 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.
- A referral to a dietitian may be helpful for some people.
- Simple exercise such as walking for 45 minutes, three times a week, at a pace that 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 to 14 days after each cycle although the effect may be earlier with certain drugs (e.g. five to nine 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 might 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 must notify your oncology team if you feel unwell, with chills and shakes, even in the absence of a high temperature.
Some drugs can affect the red blood cells, causing anaemia. Platelets (which help blood to clot) might also be affected. Lowered levels may cause bruising, nosebleeds etc. These blood 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.
- Alcohol-free 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. It's important to notify your oncology team if mucositis is severe.
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 exercise regularly. Go for a walk outside each day as this can actually give you more energy.
- Find something that you actually enjoy doing and also try to incorporate exercise into your usual day, e.g. walk upstairs rather than taking the lift, park further away from where you want to go and walk the extra distance. Build this up gradually.
- Your GP, practice nurse or a physiotherapist can work with you to devise a specific exercise plan for you.
- Let others help when your energy levels are low.
If your fatigue doesn't allow you to exercise, discuss this with your GP.
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 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.