Dense breast tissue increases the risk of breast cancer by up to four times. However, a new study suggests that few women consider breast density to be a significant risk factor.
The study, published in JAMA Network Open, surveyed 1,858 women between 40 and 76 years of age from 2019 to 2020 who reported having had a recent mammogram, had no history of breast cancer, and had heard of breast density. .
Women were asked to compare their risk of breast density with five other breast cancer risk factors: having a first-degree relative with breast cancer, being overweight or obese, drinking more than one alcoholic drink per day, never having children, and having previous breasts. Biopsy.
“Compared to other known and perhaps more well-known breast cancer risks, women should not consider breast density a risk,” says Laura Beidler, a study author and researcher at the Dartmouth Institute for Health Policy and Clinical Practice. .
For example, the authors report a 1.2- to fourfold increased risk of breast cancer, compared with a twofold increased risk associated with having a first-degree relative with breast cancer—but 93% of women said breast density. There was less risk.
Dense breast tissue refers to breasts that are composed of glandular and fibrous tissue rather than fatty tissue. It is a common and common finding in about half of women who undergo screening mammograms.
Researchers interviewed 61 participants who reported awareness of their breast density and asked what they thought contributed to breast cancer and how they could reduce their risk. Although most women correctly noted that mammograms may mask breast density by breast density, few women felt that breast density could be a risk factor for breast cancer.
Although there are several ways to reduce the risk, including maintaining a healthy, active lifestyle and reducing alcohol consumption, about a third of women thought there was nothing they could do to reduce their risk of breast cancer.
Breast density changes throughout a woman’s life, and is usually higher in women who are young, underweight, pregnant or breastfeeding, or taking hormone replacement therapy.
The level of breast cancer risk increases with the level of breast density; However, experts are not sure why this is true.
“One hypothesis is that women with denser breast tissue have higher, higher levels of circulating estrogen, which contributes to breast density and risk of breast cancer,” said Dr. Harold Burstein. An oncologist at the Dana-Farber Cancer Institute who was not involved in the study. “Another hypothesis is that there is something in the tissue that makes it thicker, which somehow predisposes to the development of breast cancer. We don’t really know who explains the observation.
Thirty-eight states currently require women to receive written notification of their breast density and potential breast cancer risk after mammography; However, studies have shown that many women find this information confusing.
Although women are usually notified in writing when they receive a report after a mammogram that says, “Your breasts have increased in density,” it’s stuck there at the bottom of the report. I’m not sure that anyone would explain to them what that means, either in person or verbally,” said Dr. Ruth Oratz, a breast oncologist at NYU Langone’s Perlmutter Cancer Center who was not involved in the study.
“I think what we learned from this study is that we need to do a better job of educating not just the general population of women, but the general public of health care providers who are doing primary care, who are ordering those tests. Mammogram,” she added.
Current screening guidelines recommend that women at average risk of breast cancer be screened every 1-2 years between the ages of 50 and 74, with the option of starting at age 40.
Because women with dense breast tissue are considered to be at higher than average cancer risk, the study’s authors suggest that women with increased breast density may benefit from supplemental tests such as breast MRI or breast ultrasound. Currently, coverage for additional screening after the initial mammogram varies by state and insurance policy.
The authors warn that “supplementary screening may not only increase cancer detection rates, but also lead to more false-positive results and recall appointments.” Doctors should use risk assessment tools when discussing the tradeoffs associated with complementary screening, they say.
“Usually it’s a discussion between the patient, the clinical team and the radiologist. Also, the patient’s family history may influence whether there is anything else to be concerned about during the mammogram. So those are the kinds of things we often discuss with patients in those situations,” Burstein said.
Breast cancer screening recommendations vary among medical organizations, and experts say women at increased risk due to breast density should discuss with their doctor what screening method and frequency is most appropriate.
“I think it’s really important for everyone to understand — it’s doctors, nurses, women themselves — that screening is not a one-size-fits-all recommendation. Because individual women have different levels of breast cancer risk, we can’t make just one general recommendation for the entire population,” Oratz said.
For the nearly one-third of women with dense breast tissue who report that there is nothing they can do to prevent breast cancer, experts say there are steps you can take to reduce your risk.
“Maintaining an active, healthy lifestyle and reducing alcohol consumption address several modifiable factors. Breastfeeding can reduce the risk. Conversely, using hormone replacement therapy increases the risk of breast cancer. ” said Dr. Puneet Singh, a breast surgical oncologist at MD Anderson Cancer Center who was not involved in the study.
Researchers say there are approved drugs such as tamoxifen that can be given to those at significantly higher risk that can cut the risk of breast cancer in half.
Finally, breast cancer doctors say that in addition to appropriate screening, knowing your risk factors and advocating for yourself can be powerful tools in breast cancer prevention and detection.
“If any woman, at any age, is uncomfortable with something going on in her breasts, if she’s uncomfortable, if she notices a change in her breasts, make sure to bring it to your doctor’s attention and get it evaluated, don’t let it go. Somebody’s going to fire you,” Oratz said.