What is Breast Density?
Breasts are made up of: Fibroglandular tissue (fibrous tissue + glandular tissue), and Fatty tissue (non-dense tissue)
Dense tissue: Fibrous tissue + Glandular tissue
- Breast density is the amount of fibrous and glandular tissue compared to the amount of fatty tissue in the breast.
Know more about breast density:
| 👵 | 🔄 | 💗 | |
|---|---|---|---|
| Often Changes with Age | May Change Over Time | Normal & Common | |
| Breast density often decreases with age, although not true for everyone. | Breast density may change overtime and is influenced with age, menopause, weight gain or weight loss. | Many people who attend breast screening have dense breasts. |
📌 Note: Breast density varies from person to person, and having dense breast tissue is normal.
How is breast density measured?
- Breast density is assessed on a mammogram and is not related to the size or feel of your breasts.
- Your breast density may change over time, so it is assessed with each screening mammogram.
Breast density is assessed using the Breast Imaging Reporting and Data System (BI-RADS) standard and grouped into 4 categories mentioned below:
📌 Note: In Nova Scotia breast density is assessed by software and automatically included in every screening results letter sent directly to clients.
Why breast density matters?
Breast Density matters for two reasons:
It can slightly increase the risk of breast cancer
Having higher breast density is associated with an increased risk for developing breast cancer.However, breast density is only one factor that influences risk and has a relatively small impact on a person’s overall breast cancer risk.
You should speak with your health care provider about your other important breast cancer risk factors.
It can make cancer harder to see on a mammogram
Both dense tissue and cancer look white on a mammogram, which can reduce visibility.Can you see the difference?
📌 Note: Breast density is one piece of a puzzle. Having dense breasts does not mean you have breast cancer or that you will develop breast cancer.
Breast Density is only one part of your overall risk
Breast density alone will not determine your overall risk. It only has a small impact on your overall risk.
Looking at all your other risk factors together provides a much better understanding of your personal risk than breast density alone.
Your overall risks depend on factors like: (click to learn more)
| 🛑 Modifiable Risk Factors | 🔷 Non-Modifiable Risk Factors |
| 👵 Age | 🍷 Alcohol consumption |
| 👨👩👧 Family history of breast cancer | 🏃 Physical activity |
| 🧬 Inherited genetic mutations (BRCA1/BRCA2) | ⚖️ Maintaining a healthy weight |
| 🎗 Personal history of breast cancer | 🚭 Smoking |
| ☢️ Previous chest radiation | 💊 Hormone replacement therapy |
| 🌸 Some reproductive and hormonal factors |
📌 Note: Talk to your healthcare provider about your risk of breast cancer. Having this knowledge will help you in determining your next steps
What can you do if you have dense breasts?
- Continue having regular screening mammograms
- Be familiar with your breasts: NSBSP-FactSheet-Oct15 NewLogos.indd
- Report any new breast changes/concerns to your healthcare provider
- Understand your overall risk
- Take steps to reduce modifiable risk factors, learn more: Breast Health | IWK NSBSP Website
Are there any additional/supplemental screening tests for those with dense breasts?
Currently, there is not enough scientific evidence to recommend other tests for individuals based on breast density alone:
Other tests such as breast ultrasound or breast MRI for people with extremely dense breasts may detect cancer but they increase false positives (showing positive results, even with no breast cancer), leading to unnecessary biopsies which don’t find cancer.
- Current screening recommendations in Nova Scotia are based on a person's overall breast cancer risk and provincial guidelines.
Learn more about high-risk categories and screening eligibility here: High-Risk Breast Screening | IWK NSBSP Website
📌 Note: Some people may benefit from High-Risk Screening based on their overall breast cancer risk- not breast density alone.
Frequently Asked Questions (FAQs)
(click on each question to learn more)
Can my breast density change over time?
Yes. Breast density can change throughout your life. Generally, breasts become less dense and more fatty with age, especially after menopause. However, density changes vary from person to person, and some people continue to have dense breasts as they get older.
Why might my breast density be different from a previous mammogram?
Breast density can change over time, particularly with age and hormonal changes. Because breast density is assessed each time you have a mammogram, your result may be different from a previous examination.
Does having dense breasts mean I have breast cancer?
No. Having dense breasts does not mean you have breast cancer. Dense breasts are normal and common.
Does having dense breast mean I am at high risk of developing breast cancer?
Breast density alone does not determine whether you are at high risk for breast cancer. Your overall risk depends on many factors, including age, family history of breast cancer, certain inherited genetic mutations (such as BRCA1 or BRCA2), previous chest radiation treatment.
Should I be screened more frequently if I have dense breasts?
Nova Scotia automatically recalls those with category D density for annual screening mammogram.
Can I tell if my breasts are dense?
No. Breast density cannot be determined by how your breasts look or feel. It can only be assessed on a mammogram by a radiologist.
Should I still have mammogram if I have dense breasts?
Yes. Mammograms remain the best screening test for most people, including those with dense breasts. Regular screening is important because it can detect breast cancer early, when treatment is often more effective.
📌 Important to Remember: Breast density is only one part of your overall breast cancer risk. Having dense breasts does not mean you have breast cancer or that you will develop breast cancer. Regular screening and understanding your overall risk are the most important steps you can take for your breast health. |