What Does Chemotherapy Treatment Involve?

The specific drugs used will vary from one hospital to another, and also according to the type of breast cancer present. The chemotherapy usually consists of several drugs given in combination, with rest intervals to allow the recovery of normal cells. The drugs can be given by mouth or by injection. The second method may require the insertion of a catheter into a large vein, e.g. a Hickman line. The treatment is performed on an outpatient basis.
 

Chemotherapy Regimens

Three commonly used regimens are outlined below. They are named according to the drugs used.
 

CMF (First Generation)
This mild regimen consists of cyclophosphamide, methotrexate and fluorouracil. Six courses of the combination are given over a period of six months. This protocol is less effective (by approximately 4%) and less likely to cause hair loss than the other two regimens.
 

FEC (Second Generation)
This combination consists of fluorouracil, epirubicin and cyclophosphamide. It is the most commonly used regimen. It is also given over six months. Recent evidence has indicated that chemotherapy regimens containing epirubicin are more effective than CMF, particularly in more aggressive tumours. However, the side-effects of epirubicin are more severe.
 

Taxane-containing regimens. (Third Generation)

Newly developed chemotherapy drugs, such as Taxol and Taxotere, are still undergoing research and evaluation by scientists. They seem to be more effective than other regimens especially in hormone receptor negative invasive cancer and are likely to be used more widely in the future. Taxanes should be used in addition to epirubicin mentioned above especially in young women with node positive breast cancer.
 

What are the Side-effects?

As mentioned earlier, chemotherapy affects cells that are growing/dividing quickly, such as cancer cells. However, it also affects some normal cells, such as blood and bone marrow cells. This causes a variety of side-effects, according to the type of blood cell involved

(Table 7).
 

Side-effects affecting other cell types include the following:

. Nausea and vomiting - is the commonest side-effect of chemotherapy. Several drugs are used to prevent this problem, such as Stemetil, Zofran, Maxalon and steroids.
. Hair loss - this only occurs with certain drugs. They damage cells in the hair root, resulting in the hair dying and falling out. A wig can be worn until the hair cells recover and the hair re-grows. Hair usually recovers to normal levels within a few months of completing chemotherapy. Cooling the scalp with an ice pack during treatment can reduce this side-effect.
. Psychological effects - feelings of depression and anxiety are common, and are usually only temporary. Counselling and social support are of great benefit, but some people may require antidepressants.
. Diarrhoea or constipation may occur in some patients.
. Irregular or absent periods - can be unpredictable and may be reversible after chemotherapy finishes. Some experts believe that the cessation of periods indicates a good response to chemotherapy.
. Reduced fertility - chemotherapy can damage the ovaries, thus reducing fertility.
. Other side-effects - these include skin sensitivity, discolouration of urine, vaginal dryness, heart problems, inflammation of the lining of the mouth and gut, heart damage, cystitis and bowel damage.

Biological Therapy

Certain new drugs can target proteins on the surface of cancer cells and block their growth. Herceptin is such a drug and can be used in some cases of invasive breast cancer that contains special proteins known as Her-2 receptors. This drug is better tolerated than chemotherapy. Her-2 positive breast cancer tends to behave more aggressively than Her-2 negative breast cancer. Herceptin can be used alone or in combination with chemotherapy in women with advanced (metastatic) breast cancer that contains Her-2 proteins. The author also recommends the use of this drug in women undergoing chemotherapy for early invasive breast cancer which is positive for Her-2. In these cases. Herceptin is given three weekly for 1 to 2 years. The drug is not recommended in patients with significant heart problems.
 

Hormone Therapy - What is it and How is it Used?

There is evidence that the female sex hormone oestrogen stimulates breast cancer to grow and to spread. Consequently, patients are advised to stop using any drugs containing oestrogen, such as the contraceptive pill and HRT, if they develop breast cancer. The use of drugs/treatments that oppose the effect of oestrogen or reduce its production can be useful in breast cancer treatment. Such drugs/treatments thatare used to manipulate the sex hormones are:
. Anti-oestrogens, e.g. tamoxifen, Faslodex
. 'Switching off' of ovaries, e.g. Zoladex
. Progestagens, e.g. Megace (are rarely used nowadays)
. Aromatase inhibitors, e.g. Arimidex, Femara, Aromasin
 

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