Breast Cancer in the Elderly: Treating this Growing Patient Population

How the disease affects aging Americans—and what additional research is still needed to improve care and outcomes

Breast cancer, like most cancer, is a disease of aging. The median age of a breast cancer diagnosis is 63 and nearly 20 percent of women diagnosed are over the age of 75, according to the Surveillance Epidemiology and End Results registry. Women in their 70s have the highest risk of breast cancer diagnosis and women in their 80s have the highest risk of death. Of the more than 42,000 patients who die from the disease each year, more than half are over 70.

While older adults represent a significant portion of breast cancer patients, there are still few standardized guidelines for how best to treat and screen this population. The first mammography guidelines for survivors of early-stage breast cancer who are over age 75, for example, were only just published in early 2021.

Here, we highlight some of the ways elderly people experience breast cancer differently—and the importance of further research to improve outcomes.

How breast cancer affects the elderly

Based on current knowledge, the biology of breast cancer in the elderly is not much different from breast cancer at younger, post-menopausal ages. Up to 80 percent of cases are ER-positive. A 2014 analysis showed that the percentage of luminal breast cancers increase with age, while the percentage of aggressive basal-like tumors decrease. While more favorable breast cancer subtypes are prevalent in older women, more aggressive breast cancers are not uncommon.

Older patients can respond to treatment differently. Chemotherapy, for example, requires a balance of providing the standard of care at recommended doses while monitoring potential toxicities (such as congestive cardiac failure and osteoporosis) and impact on quality of life. While elderly people with breast cancer are at a greater risk of side effects and treatment-related mortality, undertreatment at any age is linked to poor outcomes.

Regardless of breast cancer subtype and prognosis, patients over 75 years do not always receive appropriate treatment. Improper assessment of functional age as well as a lack of available data in older adults with cancer contribute to this disparity. It is important for patients and their caregivers to clearly define the goals of treatment with their oncologists, along with the potential side effects of treatment.

Functional age is different for individual patients. One 75-year-old person may be very independent and active, while another may be confined to home and require daily assistance. How cancer treatment affects the individual patient will very much depend on functional status. Incorporating a few basics of geriatric assessment (Has the patient had any falls? Can he/she walk one block?) into practice could better evaluate older patients and guide treatment and care. A geriatric assessment is now recommended for almost all older patients with breast cancer and is especially important in older women considering chemotherapy. The Cancer and Aging Research Group has a chemo-toxicity calculator and geriatric assessment for patients online.

The need for more research into breast cancer in the elderly

Older adults are often excluded from clinical trials, which form the basis of standards of care. This can be based on an eligibility cutoff age or a restriction to only include healthier patients. The result is a lack of clear, evidence-based guidelines on how to treat breast cancer in this group.

“Understanding how toxicities of cancer therapies will affect older patients remains an unanswered question,” said Dr. Hyman Muss, BCRF investigator and director of geriatric oncology at the Lineberger Comprehensive Cancer Center at the University of North Carolina.

“New drugs are not tested in adequate numbers of older patients,” he added. “We don’t know if they will have the same benefit or side effect profile as they do for a younger, healthier population. We have just started studies in breast and other cancers to explore these issues.”

The doctors who dedicate their practice to older patients, are a special group of individuals who often view their diagnoses through the lens of a life’s journey. 

“The geriatric oncologist is a rare breed,” said Dr. Muss.

One such oncologist, the late BCRF investigator Dr. Arti Hurria, who tragically passed away in 2018, once said of her profession:

“I am so blessed to work with this population. Because of their life’s experiences and wisdom, they can somehow appreciate and accept the boundaries of our knowledge. I advise them on their cancer, and they advise me on life. I become part of their family and vice versa. Hugs and kisses are a big part of my clinic day.”

In addition to adequate treatment guidelines for older adults with breast cancer and further study of how standards of care affect this population, there is a critical need for more oncologists who specialize in treating this population—especially as the U.S. population continues to age.