Family doctor

Overview:

• Women have a one in 12 chance of getting breast cancer
• Major risk factors include being over 40, a previous breast cancer, and a family link
• The majority of women under 64 with breast cancer are still alive after five years
• Early detection offers the best chance of a cure
• There is nearly a 100 percent cure rate for tumours less than 1cm
• Treatment involves surgery, radiation therapy, chemotherapy and drug treatment
• Regular mammograms are recommended for women over 40 

What is it?

Breast cancer is unfortunately a serious health concern for women, affecting about one in 12 women during their lifetime. Breast cancer rates have increased in most developed countries in the past 40 years.

Most breast cancer forms a lump called a malignant tumour. Cells from the tumour can metastasis (meaning spread) to other parts of the body and form secondary (in a different place/organ) cancers.

There are several different forms of breast cancer, including:

• Ductal carcinoma in situ which has a nearly 100 percent cure rate
• Invasive lobular carcinoma when the cancer starts in the milk glands and breaks through to the fatty tissue
• Invasive ductal carcinoma which starts in the milk duct and spreads to the fatty tissue. The majority of women have this type of breast cancer
• Node-positive breast cancer which has spread to the lymph nodes under the arm

Women have about one in 10 chance of getting breast cancer during their lives. The chance of getting the disease increases as women grow older. About 77 percent of breast cancer occurs in women over the age of 50.

The risk of developing breast cancer increases sharply following menopause.

At age 30 women have a one in 2525 risk of getting breast cancer, by age 40 this increases to one in 217 and one out of 24 by 60 years of age.

Men can also get breast cancer, but this is rare.

What are the risk factors?

Most women who get breast cancer do not have any specific risk factors, and the absence of the risk factors mentioned below does not offer any particular protection.

Main risk factors include a family history of the disease, being over 40 years old, previous breast cancer, a pre-malignant breast biopsy, and a breast cancer gene.

Having three or more relatives from the same side of the family with breast or ovarian cancer gives a woman a high breast cancer risk. About 15 to 25 percent of all breast cancers occur in women who have a first-degree relative who has had the disease.

Women with a breast cancer gene have more than a 50 percent chance of getting breast cancer before the age of 70.

Smaller risk factors include starting your periods before the age of 11 and not reaching menopause until after 55, having a first child after the age of 30, or not having any children at all.

The oral contraceptive pill may carry an increased risk of breast cancer. However, this has not been proven. Studies have shown long-term hormone replacement therapy of more than 7 years duration very slightly increases the risk of breast cancer being detected (but not of increased risk of death from it).

Other risk factors include high socio-economic groups, Jewish ancestry, and a high-fat diet.

It is also believed that being over weight can increase the risk of breast cancer in over 50 year olds.

Some studies have shown a link between alcohol use and breast cancer but this requires more research.

What are the symptoms?

A breast lump, swelling, discharge, or thickening could be signs of breast cancer. Any change in the breast in over should be fully investigated.

Other changes which warrant investigation include breast irritation, scaliness, nipple pain, or if the nipple becomes inverted. Most of the time these symptoms do not mean breast cancer.

A breast mammogram will help determine whether the breast change needs further investigation. A mammogram alone should never be relied on to exclude cancer in the presence of a lump or symptoms.

Those who have a suspicious abnormality will have a biopsy which takes tissue from the site for testing. A breast ultrasound may be used to help guide a needle biopsy, and to give another view of the abnormality.

It is very important not to delay seeking medical advice if you notice a breast lump or abnormality.

Treatment

Treatment depends on the stage of the cancer.

The tumour is usually removed by surgery. This can involve a lumpectomy where the tumour and surrounding tissue is removed, a partial mastectomy in which one quarter or more of the breast is removed, or a full mastectomy when the whole breast is removed, sometimes along with the lymph nodes.

In some cases, breast reconstruction is performed during the operation to remove the tumour. It may be performed at a later stage as well.

Chemotherapy or radiation therapy could be recommended following surgery, depending of the size and site of the cancer and whether the tumour is receptor negative.

Radiation therapy is normally recommended to women who have had lumpectomy and surgery to preserve the breast. It is used to kill cancer cells that may remain in the breast.

Chemotherapy is given in cycles and can be given before or after surgery. There are some unpleasant side effects depending on the length of treatment and the dose.

Some women will be prescribed the drug tamoxifen which blocks the production of the female hormone oestrogen which can increase the growth of breast cancer. Studies have found up to a 50 percent reduction in further breast cancers in women taking the drug.

Women who decide against breast reconstruction may want to be fitted with a breast prosthesis. There are special mastectomy bras available or some women get an existing bra adapted. Make sure you are happy with the fitting.

How to reduce your risk of breast cancer

Regular mammograms and early detection is the best method to reduce breast cancer deaths.

It is estimated that mammography has increased survival rates of breast cancer between 20 to 30 percent in women over the age of 50.

There is continued debate over the best age to start screening for breast cancer. The American Cancer Society advises yearly mammograms for women over the age of 40, while some experts believe one mammogram every two years is enough for women between the ages of 40 and 50.

It is generally accepted that women over 50 should have mammograms once every 2 years. Women between 40 and 50 should have them annually as in this age group cancer may arise more rapidly and be more easily missed between screenings. The divisions into age groups is somewhat arbitrary and you should discuss your individual strategy with your own doctor.

In New Zealand, a publicly funded screening programme is available for women between the ages of 50 and 64

Breast self-examination is still recommended for women over 20 to help find breast cancer in the early stages. However there is little scientific evidence of the benefit of this: most doctors believe it is prudent women to be confident in examining their own breasts, so that changes can be detected early .Your doctor should be able to teach you how to examine your own breasts and what to watch out for.

Many women unfortunately present with advanced cancer which could have been detected earlier by better breast self-examination/awareness.

Doubt has recently been cast on the value of self examinations because mammography currently offers the best hope of detecting cancer before it can be felt when there a high survival rate.

In very rare cases, some women with a strong family history, a breast cancer gene, or previous breast cancer may chose to have both her breasts removed to reduce the chances of breast cancer. However, it is possible the cancer will grow in any remaining breast tissue.

What are the survival rates?

After five years, 80 percent of women with breast cancer between the ages of 45 and 64 years will still be alive.

When breast cancer is detected before it has spread the five year survival rate is 97 percent. If cancer has spread to nearby lymph nodes the survival rate is 76 percent. If it has spread to organs such as the lungs or liver, the survival rate is about 20 percent after five years.

Breast cancer tumours less than 1cm in size are almost always cured. Those with tumours larger than 2cm fare worse.

More than 30 percent of cancerous breast tumours are not found until the advanced stages, reducing the chance of survival.

The finding of oestrogen and progesterone receptors in tumour biopsies are believed to be a good sign. There is a better prognosis than when the tumours are receptor negative.

In general, women have a one in 28 chance of not surviving breast cancer.

Future trends

Mammograms cannot detect all breast cancer. Researchers are currently studying new methods for detecting breast cancer.

Researchers are studying magnetic resonance imaging (MRI), digital mammography with the use of computers, and the use of radiation injections to find cancer sites.

Research is also underway into new treatments and prevention for breast cancer.

A world-wide study of the drug tamoxifen is being carried out to determine if it reduces the chance of high-risk women developing breast cancer.

Genetic testing for women with a family history of the disease may become more widespread in future.

Several new treatments are under investigation including bone marrow transplantation to help preserve the bone marrow after chemotherapy. Another treatment involves blood stem cell transplantation to counteract the risk of serious infection from chemotherapy.

Getting help

The Cancer Society, Auckland ph 09 524 0023 or free phone 0800 800 426

The Breast Cancer Foundation, Auckland ph 09 5224648.