Breast Cancer - Moose and Doc

A breast cancer explanations website

 

May 7, 2019 By Dr. Halls

How to find out “mammographic density” and dense breast tissue
 

Further Reading

  • Detailed cancer.org guide to breast cancer detection, including dense breast tissue” discussion.

 

Hints from a radiologist.

 

0% density

You can ask for a copy of the radiologist’s report from your last mammograms

Sometimes your mammogram report will say whether or not you have dense breast tissue. Indeed, If the report says that your breast tissue is’very’ dense, then you are probably in 75% to 100% density category. If the report says they are ‘somewhat’ or ‘moderately’ dense, then the breast tissue is probably in the 50% to 74% category. But if the report says the breasts are ‘entirely fatty’ they are probably in the 0% category. If the report says they are ‘mostly’ or ‘somewhat’ or ‘partially’ fatty, they are probably in the 1% to 24% category. Note: Some radiologists are not required to describe the mammographic density in their reports. Many radiologists do not mention anything about mammographic density, unless the density is great enough to interfere with their ability to interpret the mammograms.

What if the mammograms were taken as part of an organized screening program?

In this case, there may not be a written radiologists report, but some screening result data must be recorded somewhere. You can ask the screening program administrators if mammographic density is recorded in their databases. Many (but not all) screening programs do this, and they may be able to tell you your mammographic density.

You can ask the radiologist

who reported the mammograms, to estimate your mammographic density percentage. You can just ask “Do I have dense breast tissue?” Some radiologists would happily do this for you. Others might be too busy or hard to reach.

You can ask to see your mammo films

and judge for yourself. Some mammography centers will loan you your mammograms. Others may offer to charge you a fee to make copies of the films. Without taking your mammograms away from the mammography center, you should at least be able to look at them for free. When you look at your mammograms you can judge the density for yourself.
Do not worry too much about making an inaccurate density measurement, because even radiologists have inter-observer agreement rates of about 0.75. (i.e. a radiologist estimating the density of a mammogram is likely to differ from the consensus of a group of radiologists about 25% of the time.) It is subjective.

See these examples of what mammograms look like

  • Mammogram examples of 0% mammographic density, aka a href=”https://halls.md/density-fatty-mammogram-breast/”>fatty breasts in mammographers lingo.
  • Examples of 1% to 24% mammographic density.
  • Examples of 25% to 49% mammogram density, the most common situation in women over 50 yrs old.
  • Mammogram examples of 50% to 74% breast density on mammograms, more common in younger women.
  • Examples of 75% to 100% density, aka really “dense breast tissue” for the mammographer.
1% to 24% density
low density
25% to 49% density
mild
50% to 74% density
moderate dense breast
75% to 100% density
dense breast tissue

 

A woman’s risk of breast cancer increases if her breasts are mammographically dense. You can test this using our very own breast cancer risk calculator.

MooseFingerRight

Dr. Halls Dr. Halls
I originally made this page in year 2000, and updated the styling in 2014.

Megan Megan
Recently, some states in the USA made rules that require mammographic density to be reported on mammograms.

Dr. Halls Dr. Halls
I don’t agree with that. I think it’s bad to add verbage into mammo reports containing low-value information.

Megan Megan
Low value? Why?

Dr. Halls Dr. Halls
Suppose the report also said “she is tall, old and overweight”. Those are also risk factors and there’s nothing a woman can do to change them, or change her breast density.

Dr. Halls Dr. Halls
Organized mammographic screening programs and health insurance plans, do not let women change their follow-up booking schedule based on breast density, so they are wasted words.

Talking Moose
Talking Moose
And doctors skim reports too quickly.


 
 

The Risks of the Mammogram reports

 

  • The risk of doctors not noticing a cancer on the mammogram report. This may be because the report is too wordy and includes information about breast density and birads numbers. Sometimes the reports even include which society or government set the guidelines, and so on.
  • The risk of having more people die due to annoyance and confusion about mammograms

 

Jessica Jessica
More people will die?

Holly Holly
What? Are you serious? What are you saying?


 
 

Here is a real life Example

 
I live and work as a radiologist in the province of Alberta, Canada. If a government sets a clear guideline that women should get mammograms ever 1 year, what happens? Women tend to come for a mammogram every 2 years. Some women will develop a cancer during those 2 years and some will even die because of it. Furthermore, if a government sets a guideline that women over 50 can have mammograms annually and the rest can have mammograms every 2 years, what happens? Women tend to come every 5 years. During those 5 years there will be more cancers and more deaths.

 

Holly Holly
Wow! That’s shocking.

Harmony Harmony
Do the governments know? By promoting 2 years, the result is returning for mammograms in 5 years?


 
 

The Evidence

 
By the way, the above information is factual and let me reference it. This is data from the Alberta Breast Cancer Screening Program, presented to the Alberta Society of Radiologists meeting in 2013 or 2014.

Major screening programs and governments find the subject embarrassing, (and financially beneficial). So data like this does not get publicity or published in journals.

Another example. Every few years there will be some scientific study published somewhere, saying that mammography does not prevent cancer deaths. A flurry of scientific rebuttals and arguments will appear in medical journals for months afterwards. But most normal people see none of that. Instead, normal people see a TV reporter telling women that mammograms are of no benefit and they may see 2 doctors arguing about it on TV.

The result? Women stop coming for mammograms for around 5 years. Furthermore, during those 5 years, cancers happen and go undiagnosed for too long. Indeed, early diagnosis is key to breast cancers and undetected tumors can grow big and involve lymph nodes. As a result, more women die.

 

Megan Megan
Do the TV reporters know, that their little news report is going to kill people during the next 5 years?

Dr. Halls Dr. Halls
Nope. The only people who truly understand are a few senior epidemiologists who watch cancer rates rise and fall in waves as years go by. Furthermore, these doctors can map the “mammography controversy TV stories” onto the waves.

Megan Megan
So, what about breast density?


 
 

Dense Breast Tissue and Mammograms

 
Some of you may know that a patchwork of states in the USA have new laws regarding the reporting of breast density. Below is a map from 2014.

breastdensitylegislated

In a yellow-color state, like Colorado, here is the kind of message that goes in a letter to women:-

The dense breast tissue Letter

 

“Your mammogram shows that your breast tissue is dense. Dense breast tissue is common and is not abnormal. However, dense breast tissue can make it harder to evaluate the results of your mammogram and may also be associated with an increased risk of breast cancer. This information about the results of your mammogram is given to you to raise your awareness and to inform your conversations with your doctor. Together, you can decide which screening options are right for you. A report of your results was sent to your physician.”

 
However, the letter above will confuse women and family doctors. I believe that the states that send confusing letters about mammography will lead to women having fewer mammograms and therefore cause more cancer deaths in those states.

 

Dr. Halls Dr. Halls
Isn’t it crazy? The urge to do something that might prevent cancer deaths, can accidentally lead to more cancer deaths.

Megan Megan
So the forceful advocates who pushed these laws into existence, requiring breast density reporting, do they know this?

Dr. Halls Dr. Halls
No. They think they are helping. But I’m predicting that in 5 years there will be more cancer deaths in the yellow states, and in 10 years of arguing about it, the laws will still be there.

Holly Holly
I hope you’re wrong.

Tyler Tyler
Doc, you have no published evidence that the density laws and letters will be harmful. It’s just one mans opinion.

Talking Moose
Talking Moose
See how easy it is to discredit an opinion? All that matters is getting your mammogram.



 
 

My other website Breast-cancer.ca is where most of my breast cancer information has been accumulating.

References

 

  1. Vachon CM, van Gils CH, et al. Mammographic density, breast cancer risk and risk prediction. Breast Cancer Res. 2007 9:217.
  2. Assi V, Massat NJ, et al. A case-control study to assess the impact of mammographic density on breast cancer risk in women aged 40-49 at intermediate familial risk. Int J Cancer 2014:

 

Dr. Halls Dr. Halls
Even a webpage like this, with its discussion of controversy and confusion, might cause cancer deaths, if shared with negativity on facebook and argued about.

Talking Moose
Talking Moose
So if you like to argue in public…

Megan Megan
.. end with ‘just get your mammogram’.


 
 

 

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