With breast cancer awareness month come conversations about breast cancer prevention and early detection. Did you know that one of the biggest risk factors associated with breast cancer diagnosis and effective early breast cancer detection is breast density? Do you know if you have dense breast tissue?
Multiple studies done on screening mammography over the past 30 years have demonstrated it’s ability to lower the mortality rate from breast cancer by about a third in women who choose to get their yearly screenings. However, other studies have shown mammography’s ability to find early invasive stage 1 cancers greatly depends on a woman’s breast density.
What is breast density?
Breast density is simply the percentage of fibroglandular breast tissue in comparison to fatty breast tissue. While overall mammographic sensitivity for the detection of breast cancer is often quoted at 85-90% in women with predominantly fatty breasts, this percentage drops to 50% in women with extremely dense breast.
As women get older, their breasts often become less dense and more fatty. After menopause, the breast tissue of most women is replaced by fat. Some older women who use postmenopausal hormones may have higher breast density until they stop using hormones.
Why is cancer hard to see in dense breast tissue?
The fibroglandular part of the breast tissue appears white on a mammogram image. But cancer also appears white on a mammogram image. This “masking effect” creates a dilemma for radiologists when trying to properly detect small invasive cancers in women with dense breast tissue. In fact, they now notify you of this on your mammography screening results so you may talk to your doctor about other supplemental imaging options that might be right for you.
Radiologists face similar problems detecting cancer on mammograms of women with breast implants. The cancer again shows up as white against the white background of their implant.
How many women have dense breast tissue?
Over 40% of women have dense breasts (meaning that at least 50% of the breast tissue is fibroglandular).The lowered sensitivity of mammography in these women is a significant problem affecting a large percentage of the screened population.
Adding to the significance, is that about 70% of breast cancers occur in women with dense breasts. In fact, the risk of breast cancer in a women with extremely dense breasts in comparison to a women with fatty breasts is elevated 4-6 fold. This means these women have a similar increased risk of developing breast cancer as the increased risk of a women with a 1st degree relative diagnosed with breast cancer.
How did I develop dense breasts?
Genetic research in the past decade has revealed that dense breast tissue can be hereditary. How your breasts feel or their size does not always correlate with how dense the tissue appears on imaging, so you may not know you have this inherited trait until you get a your first breast imaging done.
What do I do about the risks of dense breast tissue?
In summary, women with dense breasts are common, they account for the majority of breast cancers, they are at higher risk of developing breast cancers, and mammography is less able to diagnose their cancers early. If you or someone you know falls into this risk category, it is important for you to know your choices for supplemental breast screenings to increase your chance of effective early detection.
- Automated Whole Breast Ultrasound screenings are most advantageous for women with a breast density grade of 3-4. Small cancers usually appear dark against the white background of dense breast tissue with this method, making the cancer more visible. Studies indicate that in conjunction with a mammogram, this full breast ultrasound screening can double the cancer detection rate in dense-breasted women and in women with implants.
- 3D Tomosynthesis is most beneficial for women with a breast density grade of 2-3. 3D Tomosynthesis improves visualization of calcifications and small cancers that can be hidden by overlapping tissue. Studies indicate this method not only increases the probability of early detection, but also decreases false positive mammograms.
- MRI – women with increased risk factor, such as a 15-20% lifetime risk for breast cancer and/or a breast density grade of 4, should discuss with their physician the benefits of having an MRI performed in conjunction with mammography.
An automated whole breast ultrasound is a great adjunct screening tool examination in women with dense breasts or breast augmentation. Consider adding it to your screening mammography. This automated ultrasound takes about a half hour, is painless, and requires no breast compression, injections or radiation. Studies show that an ultrasound examination, in conjunction with a mammogram, can find more cancers in women with dense breasts than by mammography alone. The goal is to find cancers when they are small. When cancers are diagnosed early, doctors can often prescribe less invasive treatments and/or shorten the length of treatment.
Know your breasts!
Every breast is different and feels different. Here is a great article on how to properly do a self-exam. Know what is normal for you and see your doctor if you notice any of these breast changes:
- Lump, hard knot or thickening inside the breast or underarm area.
- Swelling, warmth, redness or darkening of the breast.
- Change in the size or shape of the breast.
- Dimpling or puckering of the breast skin.
- Itchy, scaly sore or rash on the nipple.
- Pulling in of your nipple or other parts of your breast.
- Nipple discharge that starts suddenly.
- New pain in one spot that does not go away.
To learn more about Automated Whole Breast Ultrasound or to schedule your screening, please go to kvinnacare.com or call the KVINNA Breast Care + Imaging Clinic at (509) 960-5550.