BREAST CANCER AWARENESS MONTH
October is (National) Breast Cancer Awareness Month, so I wanted to share some important information, statistics, and resources with you. This post is going to be a long one, so let's just get right into it.
What Is Breast Cancer?
(the following information is from the Canadian Cancer Society)
"Breast cancer starts in the cells of the breast. A cancerous (malignant) tumour is a group of cancer cells that can grow into and destroy nearby tissue. It can also spread (metastasize) to other parts of the body." Sometimes, cells in the breasts can change and lead to non-cancerous conditions, such as atypical hyperplasia (which is a pre-cancerous condition, that may increase your future risk of developing breast cancer) and cysts (essentially, a benign, abnormal sac of fluid). These abnormal cells can also lead to the formation of non-cancerous tumors, like intraductal papillomas.
Sometimes, however, changes in breast cells can lead to breast cancer. "Most often, breast cancer starts in cells that line the ducts, which are the tubes that carry milk from the glands to the nipple. This type of breast cancer is called ductal carcinoma. Cancer can also start in the cells of the lobules, which are the groups of glands that make milk. This type of cancer is called lobular carcinoma. Both ductal carcinoma and lobular carcinoma can be in situ, which means that the cancer is still where it started and has not grown into surrounding tissues. They can also be invasive, which means they have grown into surrounding tissues. Less common types of breast cancer can also develop, including inflammatory breast cancer, Paget disease of the breast and triple negative breast cancer. Rare types of breast cancer include non-Hodgkin lymphoma and soft tissue sarcoma."
Canadian Breast Cancer Statistics
Breast cancer is the most common among Canadian women, and it is the second leading cause of death of Canadian women. While men can also develop breast cancer, it is very rare.
○ 23,600 women were diagnosed with breast cancer
○ 5,000 women died from breast cancer
○ on average, 72 women were diagnosed with breast cancer every day
○ on average, 14 women died from breast cancer every day
○ 230 men were diagnosed with breast cancer
○ 60 men died from breast cancer
○ breast cancer made up 25% of all new cancer cases in women
○ breast cancer made up 13% of all cancer related deaths in women
1 in 8 Canadian women will develop breast cancer
1 in 31 Canadian women will die from breast cancer
Types of Breast Cancer
(the following information is from the Canadian Breast Cancer Network)
There are many different types of breast cancer, some more common than others.
TYPES OF BREAST CANCER
Ductal Carcinoma in Situ (DCIS)
○ abnormal cells found within the milk ducts
○ non-invasive but can become invasive
Lobular Carcinoma in Situ (LCIS)
○ abnormal cells found within lobules
○ uncommon for LCIS to develop into invasive cancer
○ however; linked to increased risk of developing invasive cancer in future
Invasive Ductal Carcinoma
○ begins in the ducts and spreads to surrounding tissue
Invasive Lobular Carcinoma
○ begins in the lobules and spreads to surrounding tissue
○ begins as one type of cancer cell and changes into another type of cancer cell
○ less than 1% are metaplastic and it can be treated
Inflammatory Breast Cancer
○ rare; often resembles an infection
○ causes breast to appear red, swollen, tender
○ aggressive, locally advanced (spread to nearby tissue but not other organs)
○ blocks the lymph vessels in the skin of the breast
○ symptoms can develop very quickly
○ also referred to as advanced or Stage IV
○ it has spread to other areas of the body (metastasized) from where the cancer first formed
○ "Close to 1,200 Canadian women will receive an initial diagnosis of metastatic breast cancer each year. Some...who had an initial diagnosis of an earlier stage...will go on to develop metastatic breast cancer. The risk of this is highly individual, and depends on various...features of the initial tumour. Unfortunately...there are no current statistics in Canada to indicate how many people progress from early stage to metastatic. Metastasis...can happen before or after treatment. It may be the result of a recurrence of breast cancer (breast cancer that returns following a period where it could not be detected). Though breast cancer cells can spread to almost any part of the body, they most commonly spread to the bones. Other common sites include the lungs, liver, brain and skin. It is this distant site of breast cancer that is called a metastasis."
SUB-TYPES OF BREAST CANCER
Hormone receptor-positive (HR+) - refers to cancers in which the cells have receptors...that can receive signals from hormones that drive cell growth. Breast cancer can be estrogen-receptor positive (ER+)...or progesterone-receptor positive (PR+). It is helpful to know your hormone status as it can help you and your health care team decide if hormonal therapies and other treatments would be of benefit to you.
HER2-positive - known for the overexpression of the human epidermal growth factor receptor 2 (HER2) protein. HER2 proteins are receptors found on the surface of breast cells that are overexpressed in some breast cancers. In HER2-positive breast cancers, the cells overproduce the HER2 protein, which can result in the uncontrolled division and growth of cells. An estimated 20 % of breast cancers are believed to be HER2-positive. These cancers are often treated with treatments targeted to the HER2 receptor, which has greatly improved the prognosis of this disease
Triple-negative (TNBC) - refers to cancers whose growth is not driven by the hormones estrogen or progesterone, or by the overexpression of HER2 proteins. Targeted therapies developed for hormone receptor-positive and HER2-positive breast cancers are often ineffective against triple-negative breast cancers. Chemotherapy, surgery and radiation are the most effective treatments currently available for TNBC.
Breast cancer has also been divided into five major molecular subtypes:
luminal A, luminal B, HER2-enriched, basal-like, and normal.
Luminal A cancers typically tend to be HR+ and HER2-negative, with low nuclear grade.
Luminal B cancers are also HR+, but may be higher grade and may be HER2-positive.
HER2-positive breast cancers tend to be strongly HER2-positive, and HR-.
Basal like cancers are often triple negative, however these terms are not entirely interchangeable.
Hereditary Breast Cancer
(the following information is from the Canadian Breast Cancer Network)
About 5 - 10 % of breast cancer cases are thought to be hereditary breast cancer.
Having a close blood relative (immediate family member*) with breast cancer can increase your own risk of breast cancer. Inheriting certain genetic mutations can also increase your risk. The most well-known genes linked to an increased risk of developing breast cancer are the BRCA1/BRCA2 genes. A mutation in the BRCA1 or BRCA2 gene carries a lifetime risk of breast cancer (which is the risk of developing a disease over the course of your lifetime) of 40 to 85 percent.
In addition to the BRCA1/BRCA2 genes, researchers have identified several other genetic mutations that are thought to be linked to the development of breast cancer. Genetic testing...is available as an option for those concerned about hereditary breast cancer. Clinical factors that raise concern for hereditary breast cancer include young age, strong family history in first degree relatives, or multiple second degree, or history of multiple cancers in a single individual. Connecting with a genetic counsellor can be helpful to guide individuals interested in genetic testing. A genetic counsellor can provide you and your family with advice on hereditary breast cancer, the probability and risk of developing or transmitting it and the options for managing the disease and its effects. Consult your physician to discuss your options for genetic testing and getting a referral for a genetic counsellor.
*When speaking about breast cancer, immediate family member refers to:
parents, siblings, grandparents, aunts, or uncles
(all of the following information is from the Government of Canada)
There is no single cause of breast cancer, but there are some factors that can increase your risk of developing breast cancer:
○ your age - 82% of breast cancer cases occur in women over the age of 50
○ family history - especially in a mother, sister, or daughter diagnosed before menopause, or if a mutation on the BRCA1 or BRCA2 genes is present
○ previous breast disorders with biopsies showing abnormal cells
○ no full term pregnancies
○ having a first, full term pregnancy after age 30
○ in post-menopausal women: obesity and physical inactivity
○ beginning menstruation at an early age
○ later than average menopause
○ taking hormone replacement therapy for more than 5 years (estrogen plus progestin)
Breast Cancer and Your Risk
Your risk of developing breast cancer goes up as you get older. Per 2009 rates:
○ 13 out of 1,000 women in their 40s
○ 23 out of 1,000 women in their 50s
○ 29 out of 1,000 women in their 60s
○ 31 out of 1,000 women in their 70s
Biological Risk Factors
1. Getting older
○ breast cancer is most commonly diagnosed in women over the age of 50 2. Family history
○ about 5-10% of breast cancer cases are hereditary
3. Hormones, menstruation history and reproductive factors:
○ beginning menstruation before age 12
○ never having a baby
○ having your first baby after age 30
○ having a greater number of children
○ completing menopause after age 50
Some research suggests use of birth control pills can increase a woman's chance of developing breast cancer; however, studies also show use of birth control pills can help reduce risk of developing endometriosis and ovarian cancer.
Although associated with a decreased risk of developing osteoporosis, studies suggest certain types of hormone replacement therapy (HRT) may increase breast cancer risk and that risk increases with increasing duration of use. HRT is used to relieve symptoms of menopause such as hot flashes.
It is still under speculation whether or not breastfeeding does, in fact, decrease your risk of developing breast cancer. Some sources believe it does, while others are uncertain. Similarly, those that believe it does decrease your risk may be uncertain of the duration of which to breastfeed to decrease your risk.
4. High breast density
○ increased density of the breast is associated with a higher risk of developing breast cancer
○ density refers to the amount of fat in your breast tissue, and usually decreases with age; it can only be identified through a mammogram
5. Previous breast condition
○ having had a previous breast biopsy...showing non-cancerous, but abnormal cells
Lifestyle Risk Factors
1. Body weight
○ It has been found that women who gained 55 pounds or more after the age of 18...were at a 45% increased risk of breast cancer. An increase of 12 pounds after menopause has been associated with up to a 12% increased risk of breast cancer.
○ Even if you’ve been inactive most of your life, you may reduce your risk of developing breast cancer by becoming active now.
○ Increased physical activity is associated with a 25-30% decrease in breast cancer risk and helps to achieve and maintain a healthy weight.
○ There is a limited but growing body of scientific evidence that a poor diet may be linked to an increased risk in breast cancer.
○ Eating a balanced diet and choosing lower-fat dairy products and leaner meats may help contribute to maintaining a healthy body weight and a lower cancer risk.
4. Alcohol consumption
○ In a review of almost 100 research studies, it was concluded that women who drink alcohol are at over a 20% higher risk for breast cancer than those who do not drink.
○ If you consume alcohol, limit your alcohol intake to one alcoholic drink a day:
12 ounces (340 mL) of beer; 5 ounces (140 mL) of wine; or 1.5 ounces (42 mL) of spirits
○ Nearly 17% of all deaths in Canada can be attributed to smoking. Some recent studies have found a link between breast cancer and tobacco smoking and breathing second-hand smoke. However, the effects are not fully understood and more research is needed
○ Some researchers suspect that chemicals in our environment are increasing the risks of breast cancer for women. Although there is no evidence of a direct link between chemicals and breast cancer, we do not have all the answers about how chemicals affect our bodies.
○ At home, follow proper use and storage instructions for cleaning, painting and motor engine products and take proper safety precautions if you use pesticides in the garden.
○ At work, talk to your employer about ensuring good air quality and proper handling of chemicals. Read the material safety data sheets (MSDS) for chemicals and follow the directions, warnings and safe handlings procedures.
Screening and Being Proactive
(the following information is from the Government of Canada)
Evidence clearly indicates that women between the ages of 50* and 69 should have a mammogram...every two years. Talk to your health care provider about the organized breast screening program in your province or territory. If you are 40-49 years of age or aged 70 or older, you are encouraged to discuss the benefits and limitations of mammography with your health care provider.
Be proactive. Increasing your awareness and knowledge may help reduce your risk of developing breast cancer. Take action on your lifestyle risk factors. Know your body, watch for changes, and contact your health care provider with any questions or concerns about breast health and breast cancer prevention, early detection and screening.
*The recommended age to begin receiving mammograms may vary depending on your family history of breast cancer and your physician's opinion. For example, if your mother has/had breast cancer, some doctors recommend beginning mammograms at age 40 instead of 50.
Johns-Hopkins Medical Centre states that adult women of all ages should perform a self breast exam at least once a month.
“Forty percent of diagnosed breast cancers are detected by women who feel a lump, so establishing a regular breast self-exam is very important.”
While mammograms can help you to detect cancer before you can feel a lump, breast self-exams help you to be familiar with how your breasts look and feel so you can alert your healthcare professional if there are any changes.
How Should Self-Exams Be Performed?
1. In the shower
○ Using the pads of your fingers, move around your entire breast in a circular pattern...from the outside to the center, checking the entire breast and armpit area. Check both breasts each month feeling for any lump, thickening, or hardened knot. Notice any changes and get lumps evaluated by your healthcare provider.
2. In front of a mirror
○ Visually inspect your breasts with your arms at your sides. Next, raise your arms high overhead. Look for any changes in the contour; any swelling, or dimpling of the skin; changes in the nipples.
○ Next, rest your palms on your hips and press firmly to flex your chest muscles. Left and right breasts will not exactly match—few women's breasts do, so look for any dimpling, puckering, or changes, particularly on one side.
3. Lying down
○ When lying down, the breast tissue spreads out evenly along the chest wall. Place a pillow under your right shoulder, your right arm behind your head. Using your left hand, move the pads of your fingers around your right breast gently in small circular motions covering the entire breast area and armpit.
○ Use light, medium, and firm pressure. Squeeze the nipple; check for discharge and lumps. Repeat these steps for your left breast.
(the following information is from the Government of Canada)
Many common items such as underarm deodorants/antiperspirants, under wire bras, and silicone breast implants are often mistakenly associated with increased risk of breast cancer. There is currently no scientific evidence indicating these items pose additional risk for women.
(the following information is from the National Breast Cancer Foundation)
○ Several myths persist about the correlation between dairy intake and the increased risk of breast cancer. Over many decades, studies have shown that dairy consumption does not increase the risk of breast cancer.
A mammogram causes breast cancer to spread
○ A mammogram, or x-ray of the breast, currently remains the gold standard for the early detection of breast cancer. Breast compression while getting a mammogram cannot cause cancer to spread.
Antiperspirant or deodorant causes breast cancer
○ Researchers at the National Cancer Institute (NCI) are not aware of any conclusive evidence linking the use of underarm antiperspirants or deodorants and the subsequent development of breast cancer.
Canadian Cancer Society
Canadian Breast Cancer Network
Government of Canada
Breast Cancer and Your Risk
Susen G. Komen
Rethink Breast Cancer
National Breast Cancer Foundation Inc. (US)
Know The Symptoms FREE Guide
Information on Genetic Testing
Other Information / Resources