Screening Mammograms

Screening Mammograms

“Do I need a mammogram? Is a mammogram really necessary?”

This is a common question I get working with women over 40. I don’t have a simple answer for that.

Since 1980, it was recommended to start mammograms yearly at age 40. When The U.S. Preventive Services Task Force Mammogram Guidelines changed in 2016, it caused great controversy and confusion.  It recommended that women begin screening at age 50 and to only screen every 2 years. Gynecologists opposed the new guidelines but some primary medical doctors and internists agreed with them.

Who to believe? Officially, The American Academy of Family Physicians decided to sit on the bench with a recommendation of, “make up your own mind at 40”! The American College of Obstetricians and Gynecologists stuck by annual screening starting at 40. To confuse us even more, the American Cancer Society recommended that women begin yearly screening at age 45.

Yikes! What do we do with all this conflicting information? Let’s look at the facts:

Incidence of Breast Cancer by Age Group:

Taken from : The absolute risk of developing breast cancer during a particular decade of life is lower than 1 in 8. The younger you are, the lower the risk. For example:

  • If your current age is 20, the probability of developing invasive breast cancer in the next 10 years is .06%, or 1 in 1,732. This means that 1 in 1,732 women in this age group can expect to develop breast cancer. Put another way, your odds of developing breast cancer if you are in this age range are 1 in 1,732.
  • If your current age is 30, the probability of developing invasive breast cancer in the next 10 years is .44%, or 1 in 228.
  • If your current age is 40, the probability of developing invasive breast cancer in the next 10 years is 1.45%, or 1 in 69.
  • If your current age is 50, the probability of developing invasive breast cancer in the next 10 years is 2.31%, or 1 in 43.
  • If your current age is 60, the probability of developing invasive breast cancer in the next 10 years is 3.49%, or 1 in 29.
  • If your current age is 70, the probability of developing invasive breast cancer in the next 10 years is 3.84%, or 1 in 26.

After the age of 40, the incidence of breast cancer increases dramatically to 1 in 69. Why then did the US Preventative Task Force recommend waiting until 50? Two words: dense breasts.

Women under 50 have less fat and more dense tissue in their breasts.

2D mammograms were judged to just not be the right screening tool for younger women. The high density of overlapping, dense breast tissue hides cancers. With regular 2D mammograms, both cancer and dense tissue appears white, making the image difficult if not impossible to read accurately.

Women under 50 experience more false positives with 2D mammograms and are called back for more follow up tests. But isn’t it better to be safe than sorry? Yes, but what also influenced the Tasks Force decision was the fact that early, small cancers may stay small and never leave the breast.

So here, it becomes a personal decision: Do you want to take a chance that a small cancer might leave the breast tissue? Personally, I chose not to and instead opted for tomosynthesis, 3D mammography.

What is tomosynthesis, 3D Mammography?

3D mammograms take multiple pictures of breast tissue. When used for breast cancer screening, a 3D mammogram creates 3D digital images and standard 2D mammogram images. There is no need for an additional 2D image to be taken if the 3D machine is able to create what is called “c-views” to create a 2D image.

It’s not known yet if 3D mammograms reduce the risk of dying of breast cancer because the technology is less than 10 years old, introduced in 2011.

How is 3D Mammography better than 2D?

  • 3D detects abnormalities in dense breast tissue.
  • 3D has shown increased accuracy and early detection of breast cancer. Because 2D is flat, the overlapping tissues and calcifications in the breast can mask cancerous lesions.
  • 3D has less false positives, reducing unnecessary biopsies and additional testing

Should Women over 50 choose 3D?

If you are over 50 and have dense breasts, then 3D mammography is a better choice.

Should women of any age on hormone replacement therapy or bioidentical hormones get earlier mammograms and/or choose 3D?

Women on hormone replacement therapy (conventional or bioidentical), HRT, do not necessarily require 3D mammography but if the HRT makes the breast tissue more firm, then 3D mammography may be the better choice. Because some breast cancers will grow when exposed to hormones, I recommend yearly mammograms for all women on HRT.

What About the Radiation?

  • 2D Mammograms:0.4 mSv
  • 3D Mammograms: 0.5 to 1.0 mSv depending on the software used and the number of images needed.
  • Airport Body Scanner : 0.3-1.0 mSv per scan
  • Average Flight Attendant Exposure in one year: 2.16 mSv per year
  • Smoking 20 cigarettes per day: 53 mSv per year
  • Full set of Dental X-Rays: .4 mSv
  • CT chest: 7 mSv
  • Spine X-Ray: 1.5 mSv
  • Background Radiation in One year: 3 mSv per year
  • Cancer Treatment: 50,000 mSv
  • Avoiding radiation exposure is important but as you can see, the relative exposure is small. Do you want to risk getting breast cancer and the possibility of being exposed to 50,000 mSv of radiation treatment, or get a mammogram and be exposed to merely 0.4 to 1.0 mSv of radiation?

The benefits of mammography screening far exceed any risks from the small amount of radiation exposure involved. In fact, 43% of U.S. breast cancer cases are found from mammograms. Do not let your fear of a small amount of radiation stop you from getting a screening exam that may save your life.


  • 2D mammography is still the gold standard for breast cancer screening. 3D mammography is a new technology. Therefore, not all insurance companies reimburse for 3D if used for screening. Cash prices for 3D vary from $100 to $500.
  • If you choose 3D mammography, be sure to ask your doctor or radiology center if a 3D and a 2D image will be taken or if the 2D image is created by taking only a 3D image. This is important because if 2D and 3D images are taken, it doubles the dose of radiation!
  • Alternative screening techniques do not exist. Breast thermography is an unproven technology—the FDA has even issued warning letters to healthcare providers that mislead patients on its effectiveness. Breast MRIs and ultrasounds are useful diagnostic tools but have not been developed as a primary screening method.
  • Frequency of mammograms is yearly or biennial.
  • Women with a parent, sibling, or child with breast cancer are at higher risk for breast cancer and thus may benefit more than average-risk women from beginning screening in their 40s. It is generally recommended to start screening when you are 10 years younger than the age at which your relative’s breast cancer was diagnosed. For example, if the relative was diagnosed at age 45, then screening at 35 is recommended.

Questions? Email us at info@drkimberlybrown.comor give us a call at (408) 357-3422.

If you are currently a patient, ask Dr. Brown, ND if you should get a 3D mammogram. Dr. Brown, ND can order a 3D mammogram for existing patients. Schedule here.