October: Not Just Menopause Month – It’s Also Breast Cancer Awareness Month

How Common is Breast Cancer?

Breast cancer is the most diagnosed cancer among Canadian women, with 1 in 8 women expected to develop it during their lifetime1. This is a staggering statistic that impacts many of us personally. However, thanks to advancements in breast cancer screening and treatment, survival rates have notably improved. Early detection, often through routine mammography or other screening methods, helps identify cancer at an early stage when it is most treatable.

The risk of developing breast cancer increases with age, particularly for women between 50 and 69 years old2. It is a significant concern for midlife women, as it is the most frequently diagnosed cancer in this age group.  But here’s the positive news: over the past 20 years, the percentage of women dying from breast cancer has decreased by about 30% in both Canada and the United States3. Today, the death rate is around 19.4 per 100,000 women in Canada and 20.1 per 100,000 women in the United States, a significant decline from 28 per 100,000 women in 2003.

This steady decline is due to improvements in screening technologies like mammography, which allow for earlier detection, as well as advancements in treatment options, including targeted therapies and hormone treatments. While many breast cancer risk factors, such as age, family history, and genetics, cannot be changed, early detection remains the best strategy for increasing survival rates. Regular screenings can detect smaller, less-advanced cancers, improving the chances of successful treatment and reducing the need for more aggressive interventions.

Risk Factors for Breast Cancer

Understanding the factors that may increase your risk of breast cancer can help you make informed decisions about your health. Recognizing these breast cancer risk factors is the first step toward monitoring your breast health proactively.

1. Increasing Age

The risk of breast cancer increases with age. Most cases are diagnosed in women over 50.4  As we age, the accumulation of genetic mutations in cells becomes more likely. That’s why regular screenings, particularly for women aged 50 to 74, are so important. Being aware of this risk can empower women to take action.

2. Family History and Genetics

A family history of breast cancer, especially among first-degree relatives (mother, sister, daughter), significantly raises a woman’s risk. Additionally, genetic mutations, such as BRCA1 and BRCA2, can dramatically increase the likelihood of developing breast cancer.5 Women with these genetic markers are often categorized as high-risk and may require earlier and more frequent screenings. If you have concerns about your family history, our clinicians are here to support and guide you.

3. Hormonal Factors

• Menstrual and Reproductive History: Women who began menstruating early (before age 12) or experienced menopause later (after age 55) have longer exposure to estrogen, which increases breast cancer risk. Similarly, women who have never given birth or had their first child after age 30 may face a slightly higher risk due to the prolonged duration of estrogen exposure over their lifetime.
• Hormone Therapy and Breast Cancer Risk: Many women wonder if hormone therapy (HT) increases their risk of breast cancer. The answer depends on the type and duration of hormone therapy:
  • Estrogen Therapy: Women using estrogen therapy alone can do so for up to 7 years before the risk of breast cancer begins to increase. This provides some reassurance for those managing menopausal symptoms.6
  • Estrogen-Progesterone Therapy: For those using combined estrogen-progesterone therapy, the risk increases after 3 to 5 years of use. However, the risk might be lower for women who take micronized progesterone intermittently and start hormone therapy early in menopause.7,8

If you’re considering hormone therapy, it’s important to discuss the potential risks and benefits with your healthcare provider. Our clinicians are available to help you assess your health history and individual risk factors when making decisions about hormone use and breast cancer screening.

4. Lifestyle Factors

• Alcohol Consumption: Studies show that alcohol consumption increases breast cancer risk, and the risk grows with the amount of alcohol consumed. 9 Limiting alcohol intake can be a positive step in reducing this risk.9,10
• Lack of Physical Activity: Regular physical activity can lower breast cancer risk. A sedentary lifestyle is associated with a higher risk, especially in postmenopausal women.11 Incorporating exercise into your daily routine is a proactive way to support your health.
• Obesity and Body Weight: Being overweight or obese after menopause increases the risk of breast cancer. After menopause, most estrogen in a woman’s body comes from fat tissue. Higher levels of body fat can lead to increased estrogen production, potentially contributing to breast cancer development.12

5. Breast Density

Breast density is another important factor to consider. Dense breasts contain more glandular and fibrous tissue, which can appear white on a mammogram, just like cancerous tissue. This similarity can make it harder to spot abnormalities. Women with dense breasts may benefit from additional imaging methods, such as ultrasound or MRI, for more accurate detection.13

Determining Breast Density: Your breast density is assessed through mammography. Knowing your breast density is essential to determining the best breast cancer screening approach, as dense tissue may require supplementary imaging. If you’re unsure about your breast density, we encourage you to ask your healthcare provider during your next screening. Our team is also here to help guide you through understanding your breast density. To learn more about breast density and screening read our article Understanding Breast Screening: Mammograms, Ultrasound, and the Role of Breast Density

The Takeaway

Early detection through regular screenings is key to reducing breast cancer mortality. By staying informed about the factors that influence breast cancer risk, such as hormone therapy, lifestyle choices, family history, and breast density, you can make informed decisions about your health. Our team of clinicians and coaches is here to support you every step of the way.

If you have questions about your personal breast cancer risk or screening options, we encourage you to consult with one of our healthcare professionals. Together, we can create a tailored screening plan to meet your unique needs and help you take charge of your breast health.

References:

1. Canadian Cancer Society – Breast Cancer Statistics
   https://cancer.ca/en/cancer-information/cancer-types/breast/statistics
2. Health Canada Aging and chronic diseases
   https://www.canada.ca/en/public-health/services/publications/diseases-conditions/aging-chronic-diseases-profile-canadian-seniors-report.html
3. American Cancer Society
   https://www.fightcancer.org/sites/default/files/National%20Documents/Disparities-in-Cancer-Chartbook.pdf
4. Center for Disease Control
   https://www.cdc.gov/breast-cancer/risk-factors/index.html#:~:text=Studies%20have%20shown%20that%20risk,factors%20that%20they%20know%20of.
5. National Cancer Institute – Genetics of Breast and Gynecologic Cancers
   https://www.cancer.gov/types/breast/hp/breast-ovarian-genetics-pdq
6. Women’s Health Initiative (WHI) – Hormone Therapy and Breast Cancer Risk
   https://www.nhlbi.nih.gov/science/womens-health-initiative-whi
7. Estrogen therapy and breast cancer in randomized clinical trials: a narrative review
   https://journals.lww.com/menopausejournal/abstract/2022/09000/estrogen_therapy_and_breast_cancer_in_randomized.15.aspx
8. The Lancet – Estrogen-Progestin Therapy and Breast Cancer Risk
   https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)31709-X/fulltext
9. World Cancer Research Fund – Alcohol and Breast Cancer Risk
   https://www.wcrf.org/dietandcancer/breast-cancer
10. Allen NE, Beral V, Casabonne D, et al. Moderate alcohol intake and cancer incidence in women. J Natl Cancer Inst. 2009;101:296-305.
    https://pubmed.ncbi.nlm.nih.gov/19244173/
11. National Breast Cancer Foundation – Physical Activity and Breast Cancer Risk
    https://www.nationalbreastcancer.org/breast-cancer-risk-factors/
12. Mayo Clinic – Obesity and Breast Cancer
    https://www.mayoclinic.org/diseases-conditions/breast-cancer/expert-answers/breast-cancer/faq-20058458
13. Canadian Breast Cancer Foundation – Breast Density and Screening
    https://www.cbcf.org/breast-density-and-screening/