Why Do Women in Colorado Have Denser Breast Tissue

Jul 18, 2022

Article Read Time: 6 – 8 minutes

Summary of Article:
Having dense breast tissue makes it harder to find cancer on mammograms. Women in Colorado tend to have more dense breast tissue mainly because of their overall high fitness levels and healthy eating habits. But those are not the only factors affecting dense breast tissue. The five main contributors to dense breast tissue are age, hormones including hormone replacement therapy, pregnancy, menopause, and a healthy lifestyle.

Mammograms are still the first line of imaging for the detection of breast cancer, even in women with dense tissue. However, women with dense breast tissue may consider additional supplemental imaging to aid in the screening and diagnostic detection of breast cancer such as a Whole Breast Ultrasound or a Breast MRI.

What Does Dense Breast Tissue Mean?

Density refers to the amount of breast tissue versus fat within the breast. There are four categories of density assigned by the American College of Radiology:

Fatty Replaced: almost entirely fat

Scattered Fibroglandular Tissue: 25% glandular tissue to fat

Heterogeneously Dense: 50% breast tissue to fat

Extremely Dense: 75% or greater breast tissue

Denser Breast Tissue

Source: https://www.cancer.gov/types/breast/breast-changes/dense-breasts

Why is the Density of Breast Tissue Important?

Having dense tissue makes it harder to find cancer on mammograms. Breast cancer masses show up as a white density on the mammogram. Dense tissue shows up as a white background of tissue, as opposed to fat which is black on mammograms. When the background is white, it is more difficult for masses to stand out because there is no contrast.

Women with Dense Breast Tissue may have a higher lifetime risk of breast cancer if the tissue remains dense after menopause.

Many articles inappropriately connect dense tissue to increased risk – not necessarily.

We expect dense tissue in young, premenopausal women or with low BMI so this risk only holds true for women with Dense Tissue who are:

  • Older with dense tissue
  • Post-menopausal women with dense tissue
  • Increased BMI with dense tissue

How Do I Know If I Have Dense Tissue?

When you have your mammogram, the radiologist rates your density according to the American College of Radiology lexicon above. Our state has a Breast Tissue Density Notification Law to notify women on their mammogram result letter what their tissue density is. Only women with heterogeneously or extremely dense tissue receive this notification, typically the second paragraph after your results. The notification is to “inform your decisions with your referring Clinician” and does not mandate that you have supplemental imaging nor that insurance will necessarily cover the full cost.

Women in Colorado Tend to be More Active than in Other States

Colorado often claims the title of the Fittest Population in the United States. With 24 State Parks, 4 National Parks, and thousands of scenic hiking and biking trails and over 300 sunny days a year, we can be active much of the year. This activity translates to decreased body fat and decreased breast fat.

Age and Menopause Can Also Play a Role in the Density of the Breast

Many women under menopause age may have a lower body mass index (BMI) and therefore less fat in the breast. Fat content affects the size of the breasts and the density of the tissue.

Coloradans Have Healthy Eating Habits

Coloradans are often more knowledgeable about the importance of a healthy diet and exercise on their bodies.

  • Eating healthier foods typically reduces Body Mass Index- the ratio of body fat

Decreasing BMI usually also reduces the ratio of fat in the breasts. Therefore, women with healthy eating habits usually have dense breast tissue. Women who choose a healthy selection of vegetables, fruits, fish, and some lean meats reduce their breast cancer risk in all studies compared to women with healthy eating habits.

Women in Colorado are Younger on Average than in Many other States

Colorado has a relatively young average age of the people who live here, with a median age of 36 years. With a population of 5.9 million people, and 49% women.

  • That younger age translates to a more hormonal group and potentially lower body mass index.
  • Higher hormone levels translate to dense breast tissue.

Younger women tend to have more dense tissue because of the influence of the body’s hormones on the density of the breast tissue.

The average age that a woman’s body changes from hormonal (pre-menopausal) to non-hormonal (post-menopause) is 51. Every month, your hormones are trying to prepare the breast tissue for the possibility of pregnancy and nursing. That preparation uses hormones.

Women with less body fat tend to have less breast fat. This is why your breasts may become more painful at ovulation or around the time of menstruation.

After menopause, the decreasing hormonal levels signal the body to go into a more energy conservation mode where we tend to put on fat. Good fat is evolutionary, not bad. It allowed us to survive in times of starvation and when food sources were not available. Good post-menopausal fat may also be protective against some conditions that affect women more as we age such as osteoporosis.

  • The fat we gain after menopause makes our breasts fattier too and that further decreases the breast tissue density.

Coloradans Tend to Have Children Later than the Other States

If you have not had children, your breast tissue will stay dense because it has not received the signal that the tissue should become more quiescent and enter a more energy-conservative state. If your age when you had your first child is 30 or older, then the body’s breast tissue may still stay very dense for a long time, sometimes far into menopause. In addition, women who take hormone replacement therapy (HRT) after menopause typically have denser breast tissue. We are basically tricking the body into thinking that we are still premenopausal.

If I have Dense Tissue, What Can I Do to Increase Detection?

Mammograms are still the first line of imaging for the detection of breast cancer, even in women with dense tissue. However, some women may consider additional supplemental imaging to aid in the screening and diagnostic detection of breast cancer:

Supplemental imaging such as breast ultrasound is available to most women in Colorado for women at average risk of breast cancer. Some women have a lifetime increased risk for developing breast cancer based on family history or personal risk factors. These women may use Magnetic Resonance Imaging (MRI) to increase their detection.

Your clinician and you can discuss what imaging may be recommended for you. If you do not have a referring physician, Nurse Practitioner, or Physician Assistant, we recommend you talk with your radiologist. She or he can best determine your density after your first mammogram and discuss whether you may want to add an ultrasound.

Is Supplemental Imaging Like Ultrasound or MRI Covered by All Insurances?

Most insurance carriers in this state do follow the guidelines and “cover this important exam for appropriate coding indication (dense breasts).

However “covered” and “completely paid for” are different than you might think.

Although medically necessary, the dense tissue code is still a diagnostic code and therefore subject to out-of-pocket cost. The good news is that if you have met your deductible, it is typically paid completely or with a small copay by most insurances in the state. If you have any questions about whether supplemental imaging is a completely covered exam or only covered after your deductible, call your insurance company.

Who Do I Call if I Have a Question About Whether My Supplemental Imaging Is Covered?

Your insurance has made a contract with you or your employer as to what it covers. Only they and you know your exact plan and deductible. They can answer your questions regarding out-of-pocket expenses with your specific healthcare plan. Look for freestanding outpatient breast or women’s imaging centers that are not hospital-based and do not have hospital pricing.

Most importantly, make sure you are going to a facility that has experience in performing Whole Breast Ultrasound or Breast MRI

There is no such term as screening ultrasound in the insurance world because your insurance likely considers this a diagnostic imaging examination even if it is for “screening reason. We use the term surveillance ultrasound or Whole Breast Ultrasound instead because this is the intent of screening imaging: to detect smaller cancers earlier before they can be felt when they are most treatable.

About the Author:

The author of this article is the Medical Director and Chief Radiologist of The Women’s Imaging Centers- (Denver/Cherry Creek, Lakewood, Westminster, Highlands Ranch, and Centennial). For over thirty years, Dr. Kelly McAleese has been a lifelong advocate for women’s health issues and access for all Coloradans. She has published numerous articles on the topics that affect women’s health and is nationally recognized as one of the founding members of the concept of Women’s Imaging. She completed her undergraduate degree at Stanford, her Doctorate degree at Dartmouth Medical school, and her residency in Arizona before opening up the first of many Women’s Imaging Centers in Colorado to dedicate her life and entire career to specializing in preventative imaging for breast cancer.

Kelly McAleese
by Kelly McAleese