Breast Cancer

Breast Cancer

What is breast cancer?

Breast cancer is the most common cancer in women in the developed world at present. According to Department of Health figures, 602 women died from breast cancer in Ireland in 1998, accounting for 8% of all deaths from cancer in that year. This mortality rate is higher than the European average, with only Denmark and the Netherlands ranking higher than Ireland.

Breast cancer begins with the development of abnormal cells, in one or both breasts, that replace normal healthy tissue. The cancer usually starts as a small lump (tumour), which, if untreated, can spread to the muscle, skin and lymph nodes under the arm.

What causes breast cancer?

The cause of breast cancer is not yet known, but there are known genetic and hormonal factors that are known to increase the risk of developing breast cancer. The risk of breast cancer is believed to be increased for women in the following categories:

What are the symptoms of breast cancer?

Breast cancer is a possibility if a small, hard, usually painless lump is found in the breast. Bear in mind that at least 80% of breast lumps are not cancerous, but are often only fluid-filled cysts in the breast tissue. However, every lump must be evaluated. Other symptoms include:

How is breast cancer diagnosed?

Physical examination by your doctor

If you find a lump in your breast you should report it to your doctor without delay. Your doctor will examine it and arrange further investigations if necessary. Your doctor may carry out some investigations or refer you directly to a breast clinic, depending on your circumstances.


Your doctor may refer you for a mammogram (a special x-ray of the breast). This is a simple procedure that can find a lump before it can be felt. However, some breast changes do not show up on a mammogram, especially in the dense, glandular breasts of younger women, so it is important that you also have your breasts examined by your doctor.

Needle aspiration

If the doctor suspects that the lump is merely a cyst (a fluid-filled sac), it can be aspirated (ie. the fluid can be drained with a fine needle). If the lump disappears after the fluid is withdrawn, it is quite likely that the lump was a fluid-filled cyst and that no malignancy exists.


A biopsy is a microscopic examination of a tissue sample of the suspicious area and is the only way to make a definitive diagnosis of breast cancer. A biopsy can be carried out as an outpatient procedure using a hollow needle to take a sample of the tissue or all or part of the lump may be removed surgically under anaesthesia. In either case, the tissue is sent to the laboratory for analysis. This may take several days, but the vast majority of tumours tested turn out to be benign.

How is breast cancer treated?

Treatment of breast cancer can involve surgery, radiation and drug therapy, or a combination of these. Your doctor will recommend a treatment based on your age, general health, the type and size of the cancer, and whether it has spread to lymph nodes or other parts of your body.


Some form of surgery will be necessary in most cases of breast cancer. Your doctor may recommend a lumpectomy (removing the cancerous tissue only) or mastectomy (removing the entire breast). Until recently, mastectomy was the standard treatment for the majority of breast cancers, but most patients with early-stage cancers can now choose lumpectomy followed by radiation with or without chemotherapy (also known as breast-conserving treatment). Mastectomy is usually recommended only if:

  • Tumours exist in more than one site
  • The cancer is located underneath the nipple
  • Radiation therapy is not possible
  • The removed lump is large and shows cancer cells on its margins.

Advances have been made in breast reconstruction and the results can be very successful.


Radiation therapy is generally used:

  • For women with early-stage cancers who have chosen lumpectomy.
  • In premenopausal women who have had mastectomies.
  • To shrink very large tumours to a size small enough to allow surgical removal.
  • To treat cancers that have spread or tumours that are inoperable.

The radiation is administered by an x-ray machine over a period of several weeks. The side-effects of radiation therapy include fatigue, nausea, lack of appetite and the risk of burns to the breast skin.

Chemotherapy Chemotherapy works systemically — this means that it kills cancer cells throughout the body rather than just in the breast or nearby tissue. Chemotherapy or hormone therapy are the systemic treatments used for breast cancer and they may be used alone or in combination with surgery or radiation. The side-effects associated with chemotherapy include nausea, diarrhoea, temporary hair loss, weight loss, fatigue, depression, and suppression of the body's immune system. However, these side effects are usually temporary. There are fewer side-effects with hormone therapy, although hot flushes, nausea, vomiting, depression and weight gain may be experienced.

What can I do?

Be aware of the normal appearance and feel of your breasts and the changes that usually occur during the menstrual cycle, if you are still having periods. If you detect any changes from the normal pattern, specifically a lump, a blood-stained discharge or other nipple changes or puckering of the skin, report these changes to your doctor without delay.

Have mammograms every two years if you are aged 50 or over. Research shows that regular mammograms in women over 50 reduces the mortality from breast cancer. No such benefit has yet been shown in younger women. However, if a close family member has breast cancer then your doctor may recommend starting having regular mammograms at an earlier age.

Never ignore a lump or a change in the appearance or feel of your breast.

Exercise and a healthy diet are important for everyone, but particularly for premenopausal women who have a family history of breast cancer.

If you have been diagnosed with breast cancer:

Discuss your cancer and treatment options with your doctor and be sure that you understand the risks and benefits of each treatment.

Don’t suffer in silence — if your treatment is causing you pain or discomfort, tell your doctor, who may be able to prescribe relief medication.

Have regular follow-up check-ups.

Continue to examine your breasts regularly for any recurrence of the cancer.

Join a cancer support group — cancer can be a distressing disease and you may find that talking with women who have undergone a similar experience will be of help to you.

What is the outlook?

Breast cancer is one of the relatively few common cancers where survival rates are improving. This is mostly due to early detection and treatment as a result of regular mammographic screening. A complete cure or years of good health can be expected following treatment of tumours which are detected at an early stage. Cancer may recur following treatment, unfortunately. If this happens, it can usually be controlled for years by drugs, radiotherapy and in some cases, further surgery.

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