A New Study Uncovered a Common Risk For Breast Cancer—Here's How You Can Take Action Now
A Cleveland Clinic doctor breaks it down.
When it comes to cancer prevention, early detection and regular screenings are essential. It’s also important to educate yourself on risk factors and know what to look out for.
According to a new study, many women are unaware of the fact that having dense breasts increases their chances of developing breast cancer. In fact, it increases a person’s risk by one to four times.
More than 2,300 women were surveyed and interviewed regarding their perception of dense breasts as a risk factor for breast cancer. They were also asked if having dense breasts puts you at greater risk compared to having a relative with breast cancer, and what can help lower a person’s risk of developing breast cancer.
Results showed that women believe family history is the greatest risk factor, and few believed breast density increased the risk of developing breast cancer.
Given this lack of awareness, study authors note that “comprehensive education about breast cancer risks and prevention strategies is needed.”
Why Having Dense Breasts Increases Your Risk of Developing Breast Cancer
Breasts are composed of fibroglandular tissue (milk ducts, lobules and connective tissue) and fat. Breast density is used to describe the amount of fibroglandular tissue a patient has in their breasts. Breasts are considered “dense” if there is more fibroglandular tissue than fat, Dr. Laura B. Shepardson, MD, MS, and head of breast imaging at Cleveland Clinic explains.
Approximately 50% of the population between the ages of 50 and 74 has dense breast tissue. And while it's clear that patients with dense breast tissue have a 1 to 4 times greater risk of developing breast cancer than patients with less fibroglandular tissue, it's not clear why this is, Dr. Shepardson explains. One theory is that breast cancers develop in the cells of the fibroglandular tissue. Therefore, it makes sense that the more fibroglandular tissue a patient has, the more cells there are at risk of turning into cancer.
Another equally important reason why breast density matters is because breast cancers may not show up well on a mammogram if a woman has dense breast tissue, Dr. Shepardson adds. Fibroglandular tissue is white on a mammogram. Since cancers are also white, the dense white tissue can “hide” a breast cancer making it more difficult for a radiologist—a doctor who interprets mammograms—to see it.
Related: Here Are the 9 Biggest Signs of Breast Cancer in Women—and When to See a Doctor
How to Figure Out if You Have Dense Breasts
Breast density is based on the mammographic appearance, and not on how breasts feel. When a radiologist reads a mammogram, she/he will assign the breast density.
Radiologists classify density using four categories based on the percentage of fibroglandular tissue (white on a mammogram) compared to fat (gray on a mammogram) in the breast, Dr. Shepardson explains. Fortunately, many states have now passed legislation that requires radiologists to notify patients if they have dense breast tissue.
Action Steps for Screening
It is never too early to start talking about breast health with your medical provider, Dr. Shepardson says. She/he can review your specific risk factors for developing breast cancer, and with your input, adopt a breast cancer screening strategy that works for you.
“I advise all patients to consider starting annual screening mammography beginning at age 40, since younger patients tend to have denser breast tissue and early detection is key,” says Dr. Shepardson. “If a patient knows they have dense breasts, I would also advise they talk with their provider about what other screening tests, including whole breast ultrasound and/or MRI, might be right for them.”
Next up: These Are the Different Stages of Breast Cancer—and What Each One Means
JAMA Network Open: “Perceptions of Breast Cancer Risks Among Women Receiving Mammograph Screening”
American Cancer Society: “Breast Cancer Risk Factors You Cannot Change”
Laura B. Shepardson, MD, MS, Head, Cleveland Clinic Breast Imaging