Breast Density

My Category D Breasts

No. Not cup size D, category D. I’m lucky to fill a B cup on a good day. Category D refers to my breast density, not cup size.

Until earlier this week, I was more interested in my cup size. Then I learned that having extremely dense breasts is a more significant risk factor than having a family history of breast cancer. Shocked? I was, too. Especially when I realized that I have extremely dense breasts.

Breast Cancer Screening

I was given a referral for a mammogram at age 40 to get a baseline. I now consider myself lucky as that is not part of the current breast screening guidelines in my province. Mammogram screening every 2 years starting at age 45 is the current recommendation in Alberta. For details on screening guidelines by province and territory, check out

Mammogram Report Normal

My mammogram report was normal. My doctor did say that I had dense breasts and that I should have a yearly mammogram. I hadn’t really been worried, but was relieved. Problem is, I didn’t have all of the facts.

Supplemental Screening

I continued to have yearly, normal mammograms. Blissfully ignorant. Then I got a letter in the mail 2.5 years ago. It read:

“The result from your November 2020 appointment recommended that a breast ultrasound be performed on or shortly after March 23, 2021 to closely monitor changes in your breast tissue.

Our records show that a follow up exam has not been booked or performed as recommended.

It remains very important that you have this done to complete your assessment. Please feel free to follow up with your physician’s office directly.”


Panic over breast densityIt was already the second week of March 2021! Why did no one make the appointment for me?! Why didn’t anyone tell me that there was a problem with my last mammogram?!?

I immediately phoned my doctor’s office. They said they would get back to me. The next day I called again. They said they were having trouble finding my exams results. Could I come in later that week to discuss with the doctor? They assured me there was nothing to worry about.

I Was Worried

I saw my doctor who said that because I have dense breasts, the radiologist wanted me to have a screening breast ultrasound. Should I have asked more questions? Yes. But I was too concerned about getting the ultrasound booked ASAP. So I left my doctor’s office and called the radiology clinic.

I was booked in a few days later.

The Breast Ultrasound

I tried to ask the ultrasound technologist questions, but they wouldn’t say much beyond what I already knew.

The technologist finished the exam, but asked me to stay in the exam room. They were going to show the radiologist the results, and they may need to take more images. Oh. My. God.

After what seemed like an eternity the technologist came back and said, ‘you are free to go. Your doctor will have the results in a few days.’ A moment of relief.

And then all I could think about was…

Do I Have Breast Cancer?

When I saw my doctor the following week, they assured me that everything was fine. They explained that women with dense breasts have a lot of fibrous and glandular tissue. This can make screening more challenging. This is why they like to do supplemental screening. I was relieved.

More Breast Imaging

A little over 5 months later I got another letter like the one above. It said: ‘Our record show that a follow up exam has not been booked or performed as recommended.’ And this time they wanted to perform a diagnostic mammogram and breast ultrasound.

Why were these appointments not getting booked? Why the need for the scary letter if everything was fine?!

Is This Just Part of Having Dense Breasts?

I went in for the mammogram and ultrasound that I scheduled. The technologists were pleasant and said that yes, breast density often requires more screening.

The radiologist didn’t need more pictures.

A week later my doctor confirmed that everything was again fine.

Dense Breast Tissue = More Tests

This pattern continued until March 2023.

I had stopped panicking when I got the letters saying that my supplemental screening had not yet been booked as recommended. I just booked what I needed to and immediately followed up with my doctor shortly after each exam.

Breast Imaging Technologist

During my March 2023 ultrasound, of my left breast only, the technologist was much more forthcoming.

When they handed me a paper towel to wipe off the ultrasound gel, I asked if I should stay put until the radiologist had seen the images. They said ‘no. You are good to go. The nodule in your right breast has gotten smaller over the last two years. Typically we only follow these for two years, and it’s fine.’

I said, ‘great. Thank you!’ And then thought how helpful it would have been if a technologist had explained the nodule and the follow-up protocol at some point during the last 2 years.

My doctor’s office called the morning after the ultrasound and said that everything looked good. They also told me that the area they had been monitoring had gotten smaller. As a result, the radiologist thinks it is likely a cyst with some debris which is normal. But it could also be a fibroadenoma. They want me to do my routine mammogram screening September as well as ultrasound screening for both breasts. I will get a reminder call for those appointments.

Timely information is powerful.

Fibroadenoma (FY-broh-a-deh-NOH-muh) is a benign tumor made up of fibrous and glandular tissue. Fibroadenomas may go away on their own, but can require removal if they continue to grow. They often get smaller after menopause. Most fibroadenomas do not increase the risk of breast cancer.

Breast Density and Breast Cancer Risk

Last week I met Jennie Dale, who is a co-founder of Dense Breasts Canada. Jennie explained to me the importance of helping women with dense breasts advocate for better screening. I learned about all of the incredible work Jennie and the volunteer team are doing to improve awareness of breast density and it’s associated breast cancer risk.

Then Jennie said that women with extremely dense breast tissue have a higher risk of developing breast cancer compared to women with a family history. Pardon?!

We continued to talk and Jennie continued to share more alarming information about breast cancer risk and breast density.

Breast Density Categories

Breast density
Extremely dense breasts

As soon as we got off the phone, I went to my medical records file. My new doctor had given me a copy of my last mammogram report. Right there in the second paragraph:

“Volpara categorized breast density as ACR category D – extremely dense, which lowers the sensitivity of mammography.”

(Volpara is an AI tool used to assess breast density and provide clinical decision support. ACR stands for American College of Radiology.)

When it comes to breast density, category D is the highest. Category C and D are considered dense breasts. Category A breasts are mostly fat (fatty breasts). Breasts that have scattered areas of fibrous and glandular tissue, but also quite a bit of fat are classified at category B.

Extremely Dense Breasts

Extremely dense or category D breasts come with increased risks:

  • Dense breasts increase the risk of getting breast cancer; more than a family history.
  • Women in category D have a 4 – 6 times greater risk of developing breast cancer than women with fatty breasts.
  • Dense breasts increase the risk that cancer can be missed on a mammogram.
  • Mammograms find 81-93% of cancers in women with fatty breasts .
  • Mammograms miss up to 43% of cancers in women with the densest of breasts.

Cancer Risk vs Cancer Screening Risk

My new doctor is amazing. And although she did not share the alarming facts that Jennie provided above, she did review my breast screening results thoroughly. We discussed that my level of breast density warranted breast magnetic resonance imaging (MRI). This test is scheduled for this coming fall.

Breast MRI is used for women who are at high risk for breast cancer. I also learned last week that there are risks of false positives and potential risks associated with the contrast dye used for the test, called gadolinium.

I plan to discuss the risks of the breast MRI vs my breast cancer risk factors with my doctor next month during my annual physical.

Taking Hormone Replacement Therapy

I also plan to discuss the daily dose of progesterone I am taking with my doctor. My discussion with Jennie Dale revealed that breast density increases in women taking hormone replacement therapy. I suspect the benefits (which are many) of the progesterone I am taking outweigh the increased dense breast tissue risk. But it’s an important conversation with many factors to consider.

The Hero Bit

There are a few things I am now going to be proactive about since my conversation with Jennie Dale.

Do You Have Dense Breasts?

I am going to tell everyone about the importance of knowing your breast density and it’s impact on one’s breast cancer risk. Want to know more? You can read the article I wrote based on my conversation with Jennie and the incredible resources she and the Dense Breast Canada team have created here.

Breast Imaging Reporting

I am going to thoroughly read all of my medical imaging reporting and data, particularly my breast imaging reporting, more carefully.

In my November 2020 screening mammogram report, there was a paragraph at the bottom of the letter

Medical File
Thoroughly read before filing away

that stated “your breast density on this mammogram was assessed as extremely dense. Breast density is one of many risk factors that can impact your risk of cancer.”

At the time, I read the first line that said my mammogram was normal and filed the letter away.

Important to note, that Alberta started informing women directly about their breast density in October 2020. Coincidence that I was sent for supplementary screening a month later?

Ask More Questions

In addition to thoroughly reading my medical letters and documentation. I am going to ask more questions. Of everyone.

I will no longer make assumptions that no news is good news. I will not assume that someone else will make sure things get booked or followed up.

Provide More Information

As mentioned above, I plan to speak to my doctor about the breast MRI she suggested. I have since learned that the contrast die used in the test is gadolinium. Both the FDA and Health Canada advise that gadolinium can build up in the brain.

As per Health Canada, the potential side effects are unknown. Their advice is to use the lowest dose needed and to carefully consider whether repeated doses are required.

I don’t think my doctor knows that I have had an MRI with a gadolinium based contrast agent in the last 10 years. And that may change her recommendation for a breast MRI.

Take Charge or Leave It To Chance?

Most of us tend to put ourselves and our health last. Your health story is going to happen. The question is will you take charge? Or will you leave it to chance?

As per Dense Breasts Canada:

  • Women in their 40s who have mammograms are 44% less likely to die from breast cancer than those who don’t.
  • Women with dense breasts should have supplemental screening.
  • More than 40% of women, between the ages of 40-74 have dense breasts.
  • The only way to determine breast density is with a mammogram.
  • Screening access across the country is not equal; visit to find out the guidelines in your province or territory.