If a patient’s breast cancer is detected early enough, the five-year survival rate is well over 95%, say experts. In 2005 breast cancer caused 502,000 deaths worldwide. It is estimated that about 12% of all women either already have or will develop breast cancer during their lifetime. Globally, breast cancer is the forth most common cause of cancer death, after lung cancer, stomach cancer, liver cancer and colon cancer. For women globally, breast cancer is the most common cancer and the most common cause of cancer death. The number of breast cancer cases increased substantially since the mid 1970s.
Breast cancer does not only affect women. Men can also develop the disease.
According to the Canadian Cancer Society, the Canadian breast cancer death rate is going down as a result of better screening and more effective treatments. This is also the case in most industrialized countries.
Heather Chappell, Senior Manager, Cancer Control Policy, Canadian Cancer Society, says “As we enter Breast Cancer Awareness Month, we celebrate the progress that has been made against this devastating disease that affects so many women and their families across Canada. However, inroads must continue to be made against this devastating disease that continues to take a significant toll. It is the most common cancer among Canadian women.”
Since 1986 the age-standardized death rate for breast cancer has dropped by 25% in Canada. Evidence indicates that organized screening with mammography and clinical breast examination have been major contributory factors towards the falling death rates.
Chappell said “We know screening works. Barriers to screening must continue to be identified and overcome. If more women are screened, more will survive.”
The following guidelines are recommended by the Canadian Cancer Society:
— Every woman aged 50-69 should have a mammogram every two years
— Women aged 40-49 should consult with their doctors about their risk of breast cancer and the benefits and risks of mammography
— Women over 70 should discuss a screening program with their doctors
— Women over 40 should have a clinical breast examination by a trained health professional at least once every two years
— Women are encouraged to get to know their breasts and to discuss any detected changes with their doctors
Chappell said “We encourage women to be familiar with their breasts so they know what is normal for them. We no longer recommend routine breast self-examination as a way to find cancer. While it’s important for women to look and feel for any changes in their breasts, they don’t need to follow a particular technique or schedule. Many women have found their own cancers, and being aware of what is normal for them is an important part of this.”
The ultimate goal with breast cancer is to find out how to prevent it in the first place, as is the goal with all cancers, explained Chappell.
What is Breast Cancer?
Breast cancer is a tumor that has become malignant – it has developed from the breast cells. A ‘malignant’ tumor can spread to other parts of the body – it may also invade surrounding tissue. When it spreads around the body, we call it ‘metastasis’.
A woman’s breast consists of lobules. Lobules are milk-producing glands. The breast is also full of ducts – milk passages that connect the lobules to the nipple. There is also fatty and connective tissue surrounding the ducts and lobules – this is called stroma.
The most common breast cancers start in the cells around the ducts. Others can start in the cells that line the lobules. A smaller number of breast cancers can start in other parts of the breast.
The human body has two ways of moving fluid about. One is through the blood stream, which carries plasma, red and white blood cells and platelets. Lymphatic vessels carry tissue fluid, waste products and infection fighting cells (immune system cells). Immune system cells are located in the lymph nodes – the nodes are shaped like a bean.
It is common for cancer cells to grow in the lymph nodes. They get there via the lymphatic vessels.
The lymphatic system of the breasts connects to the lymph nodes in three areas: Under the arm (axillary lymph node), in the chest (internal mammary node) and by the collarbone (supra or infraclavicular node).
Doctors guess that if cancer cells are in the lymphatic system, they are most likely to be in the bloodstream and will spread to other organs in the body. It is very hard to test for breast cancer cells in the bloodstream.
If breast cancer cells have got to the nodes under the arm (axillary), it will most likely swell. Whether or not it has swollen there, will decide what type of treatment a patient should have. If cancer cells are found in more lymph nodes, then the likelihood of it turning up in different parts of the body is greater. However, there is no hard and fast rule here. Women have had swellings in many nodes and did not develop metastases, while some women with no swellings in their nodes did.
Most breast lumps are benign
A benign tumor cannot spread to other parts of the body – it stays inside the breast. They pose no threat to the patient’s life. They are not cancer. Some of them, however, can increase the woman’s chance of developing breast cancer later on. Tumors such as papillomas and atypical hyperplasia are examples of this.
How common is breast cancer?
Breast cancer is the most common cancer for women. About one in every nine women will develop breast cancer in her lifetime. 99% of all breast cancers are diagnosed in women, 1% affect men.
In the USA there were 100,000 new cases in 1985. In 1994 the number rose to 180,000. The main reason for the increase is better awareness leading to more diagnostic tests.
Why do some women get breast cancer?
We don’t know the answer to that yet. We know that heredity plays a part. The more close relatives a woman has who had breast cancer, the higher is her risk of developing it.
Written by: Christian Nordqvist