Have your Pap smear with us and enjoy a SPECIAL RATE of $40 for Mammogram done at any NHG Diagnostics centres.
Click here to learn more now!

1. What does systemic treatment consist of?

There are two questions to answer for a woman with breast cancer considering systemic treatment:

• Does she need the systemic treatment
• Which type of systemic treatment?

Low Risk:

• Oestrogen receptor positive
• Lymph node negative
• Grade 1 (well differentiated) tumour
• Tumour size less than 1 cm

High Risk:

• The rest

Women in the low risk group are offered tamoxifen or none while women in the high-risk group are offered systemic treatment.

Type of Systemic Treatment

There are 3 main forms of systemic treatment:

1. Cytotoxic Chemotherapy
2. Hormonal Manipulation
3. Ovarian Ablation

Cytotoxic Chemotherapy

This is the administration of toxic drugs usually into the veins (intravenous). Research has identified these drugs as effective in killing cancer cells, at the same time they are toxic to our body. Hence they are administered at controlled dosage over a period of time to limit their toxicity and at the same time achieve their target of eliminating cancer cells.

There are 3 main regimes, each a combination of cytotoxic drugs and the doctor will select which regime is most suitable for the patient. The drugs are then administered at 3 weekly intervals over 4 to 6 months. These regimes are:

• CMF (cyclophosophamide, methotrexate and 5-florouracil)
• AC (Adriamycin, cyclophosophamide)
• Taxol based regime

1. What are the side effects?

Most patients are concerned about the side effects of cytotoxic chemotherapy and it is important to answer a few key questions.

Can cytotoxic chemotherapy kill? Fortunately death resulting from chemotherapy is very uncommon with an incidence of 0.9% reported from one large chemotherapy study. Deaths are caused by overwhelming infection or formation of blood clots in the veins (thromboembolism) and occur in very sick patients.

2. What is the immediate side effects and how to cope with them?

Even though these acute side effects can be severe, they are usually tolerable and temporary.
List of immediate side effects following chemotherapy:

• Low total white cell count (Less than 2000/mm3)
• Fever
• Infection
• Nausea
• Diarrhoea
• Hair loss
• Platelets count (Less than 50,000/mm3)
• Thromboembolism
• Cystitis
• Weight gain (More than 10%)

Women on chemotherapy can seek advice on how to cope with these side effects from various sources:

• Reading materials
• Doctors and breast care nurses
• Support groups

3. What about long term side effects?

3 major long-term side effects associated with chemotherapy have been identified:

• Premature Menopause. A woman in her forties has a 50% of premature menopause if she undergoes chemotherapy. The effects of menopause is more severe in a younger woman and varies from hot flushes, palpitations, dry skin to more debilitating conditions such as osteoporosis and increased risk from cardiovascular disease. Fortunately a lot can be done to alleviate these effects.

• Cardiac Toxicity. Adriamycin (alias Doxorubicin) is a commonly used drug in chemotherapy, which unfortunately has an effect on the heart, which could lead to heart failure. The incidence of this side effect is low (less than 5%) and can be decreased by several measures:
  • Assessment of cardiac function in women receiving adriamycin based chemotherapy
  • Limiting the dose administered (cumulative dose of less than 300mg/m2)
  • Method of administration

• Risk of a Second Cancer.  A few cases of chemotherapy-induced leukemia (cancer of the white blood cells) have been recorded.  Fortunately this serious side effect is rare in long-term studies of patients after chemotherapy. 

Hormonal Manipulation

This term refers to measures to alter or stop the secretion of estrogen in the woman’s body in order to treat the breast cancer. These measures are:

• Tamoxifen. This is a well-known drug that has been used to treat breast cancer for the last 20 years. It is given orally once daily (20mg) and is well tolerated with little side effects. It is effective for the following categories of women:
• Women at high risk of breast cancer as a preventive drug.
• Women whose breast cancer is oestrogen receptor positive (ER+) and is at low risk of recurrence, tamoxifen is given as the sole systemic drug.
• Women whose breast cancer is ER+ and at high risk of recurrence. Hence tamoxipfen is combined with chemotherapy or other measures of hormonal manipulation. (See table for further details)

Ovarian Ablation

This refers to methods to stop the secretion of oestrogen in a woman’s body in order to reduce the stimulation of cancer cells and hence reduce the chance of cancer recurrence. This method applies only to premenopausal women and lead to premature menopause. Ovarian ablation can be achieved by surgical and non surgical methods:

• Surgical Oophorectomy. Surgery is required and is permanent.  Seldom used nowadays.

• Radiation Castration. Radiotherapy given to the patients over a 2 weeks period can “dry up” the ovaries, and stop the secretion of oestrogen permanently. It is a quick and relatively painless method

• Ovarian Suppression. Secretion of oestrogen by the ovaries is under the control of a master gland (pituitary gland) situated in the brain. Drugs known as GnRHagonist or Groserelin can alter this control mechanism leading to temporary suppression of oestrogen secretion. Ovarian function usually recovers once the drug is stopped. This drug is usually administered via a subcutaneous injection once a month or once in 3 months. This is a relatively expensive method.

Research has shown that ovarian ablation is as effective as chemotherapy in the systemic treatment of women with breast cancer. For women at high risk from cancer recurrence and whose cancer is ER+, ovarian ablation can be an alternative to chemotherapy.

ER=Estrogen Receptor, tam=Tamoxifen, ChemoRx=Chemotherapy and Radiotherapy

1. What are the side effects of tamoxifen?

About half of the women on tamoxifen will suffer from menopausal symptoms e.g. hot flushes, vaginal discharges, and irregular menses. However these symptoms have not caused women to stop tamoxifen as the compliance rate is about 70%.  An uncommon side effect of tamoxifen therapy is ocular toxicity resulting in cataract formation.

Women taking tamoxifen should not get pregnant, as the effects of tamoxifen on the foetus are unknown. There are 2 serious side effects, which have caused women taking tamoxifen much worry.

• Tamoxifen can stimulate the growth of the lining of the uterus (called endometrium) leading to thickening (called hyperplasia) and occasionally the formation of uterine cancer. The clinical presentation is irregular unusual vaginal bleeding and diagnosis is made by an ultrasound scan of the uterus and/or D & C (Dilatation and Curettage) procedure to obtain tissue for microscopic examination.  The incidence of uterine cancer is rare but as a precaution women on tamoxifen should have a 6 monthly gynaecological review with ultrasound scan.

• In women taking tamoxifen there is a higher risk of blood clot formation.  This can lead to inflammation of surface veins (phlebitis) or deep veins thrombosis (DVT). DVT can be a serious life threatening condition because of the possibility of pulmonary embolism but its incidence is rare in women taking tamoxifen (less than 1%).

N.B. Good news. Tamoxifen is also known to have several beneficial effects apart form its effect on inhibiting cancer growth.

• Maintaining bone density in postmenopausal women thus preventing osteoporosis.

• Lowering blood cholesterol leading to a lower risk of cardio vascular disease.

• Lowering blood cholesterol leading to a lower risk of cardio vascular disease.