Breast DensityA patient guide

What is Breast Density?

• Breast Density refers to the amount of fatty tissue and fibro-glandular tissue seen in the breast by mammogram. This is not something that can be felt on clinical breast exam. Breast Density is categorized into four different levels. • Fatty – 10% of women• Scattered fibroglandular density – 40% of women• Heterogeneously dense – 40% of women• Extremely dense – 10% of women

Dense Breast Tissue

• Approximately 50% of women undergoing screening mammography are classified as having either "heterogeneously dense" or "extremely dense" breasts. For all of these women, the patient letter will inform them that they have "dense breast tissue." This is significant because the denser the tissue is it may make it more difficult to detect breast cancer (masking). The sensitivity of the mammogram (chance that disease will be detected) decreases with increasing density. Mammogram, however, is still recommended as a screening for breast cancer as there are many breast cancers that can only be detected by mammogram.

What is the risk of Breast Cancer by age?

• It is important to understand that every woman’s risk of breast cancer increases with age. The risk of being diagnosed with breast cancer during the next ten years of your life is as follows:

• -Age 30: 0.44% 1 in 227• -Age 40: 1.47% 1 in 68• -Age 50: 2.38% 1 in 42• -Age 60: 3.56% 1 in 28• -Age 70: 3.82% 1 in 26

How does Breast Density affect Breast Cancer Risk?

• Having Dense Breasts is considered a risk factor for breast cancer. Only 10% of all women have "extremely dense" breast tissue, which is associated with a relative risk of breast cancer of approximately 2 compared with average breast density. This means at the age of 50 instead of having the 1 in 42 chance of breast cancer, the risk is 1 in 21.

• Forty percent of women have "heterogeneously dense" breast tissue, which is associated with a relative risk of approximately 1.2. This means at the age of 50 instead of having the 1 in 42 chance of breast cancer, the risk is 1 in 35. Therefore, breast density is not a major cancer risk factor.

Overall risk

• A person’s overall risk of breast cancer depends upon other risk factors such as gene mutations, family history, and personal history. These factors combined with age and density can aid in deciding what the best breast cancer-screening plan is on an individual basis. The strongest risk factors for breast cancer are:• Age• Sex• Personal history of atypia on a prior biopsy (ADH, ALH, LCIS)• First degree relative with premenopausal breast or ovarian

cancer

What are other breast cancer screening options are there?

• MRI• Ultrasound• Tomosynthesis (“3D

Mammogram)•  

• Screening breast MRI has been shown to substantially increase the rate of cancer detection.

• It is recommended in patients who are at very high risk (>20% lifetime risk) based on American Cancer Society guidelines.

• For patients at "intermediate risk," such as those with a personal history of breast cancer or a prior biopsy diagnosis of atypia (equivalent to a 15% to 20% lifetime risk), a patient-centered shared decision-making approach is recommended

ScreeningMRI

• Screening breast ultrasound has been known to increase the number of false-positives. The positive biopsy rate for lesions detected on screening mammography is 25% to 40%, while the positive biopsy rate for lesions found on screening ultrasound is 5-10%.

• This means that 90% to 95% of biopsies initiated by the screening ultrasound in women with negative mammograms end up showing no cancer.

Screening

Breast Ultrasound

• Screening breast tomosynthesis (“3-D mammography”) increases breast cancer detection and decreases the rate of false positives and biopsies, compared to traditional mammography, particularly in women with dense breasts.

• Although the radiation dose of tomosynthesis is slightly higher than mammography, it is still within FDA limits.

Screening

Breast

Tomosynthesis

Recommendations…

ACR• The American College of

Radiology – they encourage education and awareness of the public, but do NOT currently have any recommendations for any additional action or testing.  

ACOG• The American College of

Obstetricians & Gynecologists – As of April 2014, they do not recommend routine use of alternative or adjunctive test to screening mammography in women with dense breasts who are asymptomatic and have no additional risk factors.

Is there insurance coverage for additional screening?

• The New Jersey legislature mandated insurance coverage for any supplemental breast cancer screening deemed medically necessary in patients with “Extremely” dense breasts or those who have other risks factors.

• Currently there are no insurance billing codes for screening breast ultrasounds or tomosynthesis.

• Screening breast MRI is usually covered for high-risk women, but not for women at average risk who simply have dense breasts. Women who desire supplemental screening (whether it be ultrasound or MRI) may be asked to pay out of pocket.

References

• The American College of Obstetricians and Gynecologists Committee Opinion No 593. Management of women with dense breasts diagnosed by mammography. Obstet Gynecol 2014 April; 123(4); 910-911.

• Lipson JA, Hargreaves J, Price ER et al. Frequently asked questions about breast density, breast cancer risk and the breast density notification law in California: A consensus document. www.breastdensity.info.

• Mass, Sharon. Discussing Breast Density, A Toolkit for the New Jersey Obstetrician Gynecologist, American Congress of Obstetrician and Gynecologist, New Jersey Section. May 2014.

What next….

• If you feel you have risk factors, you may make an appointment with your doctor to discuss which screening modality is right for you.

• If you do not have risk factors then yearly screening mammography starting at age 40 is our current recommendation.