Should Race and Ethnicity Factor into Starting Ages for Mammography Screening?

Could race and ethnicity-adapted starting ages for annual mammography screening have an impact in addressing disparities with breast cancer outcomes?

Examining this possibility in a recent study published in JAMA Network Open, researchers reviewed data from 414,374 deaths from invasive breast cancer that occurred between 2011 and 2020 in the United States. Utilizing 10-year cumulative risks of breast cancer-specific mortality, the study authors calculated risk-adapted starting ages of breast cancer screening by race, ethnicity, and age. They noted that dividing total breast cancer deaths at five-year age intervals by the total person-years for that age group provided age-specific mortality rates.

The researchers found significant variation by race and ethnicity for breast cancer-specific mortality for women between the ages of 40 and 49. The breast cancer mortality rate for Black women in this age group was 27 deaths per 100,000 person years in comparison to 15 deaths/100,000 person years for White women and 11deaths/100,000 person years for Asian/Pacific Islander groups, Hispanic women, and American Indians.

Recognizing the variation in different guidelines for the recommended starting age for screening mammograms, the researchers examined mean 10-year cumulative breast cancer death risk thresholds for initial mammography screening to begin at 50, 45 and 40 years of age. Noting a mean 10-year cumulative breast cancer death risk threshold of 0.329 percent for mammography screening that begins at 50 years of age, the study authors found that Black women would reach the risk threshold by the age of 42 in comparison to age 51 for non-Hispanic White women, age 57 for Hispanic women and American Indians, and age 61 for Asians and Pacific Islander women.

In light of these findings, the researchers suggested that initial mammography screening could be delayed in lower-risk populations such as Asian and Pacific Islander women and that accelerated timing would be beneficial for Black women who have significantly higher breast cancer mortality risk.

“Although Black women may experience disproportionate rates of false positives because of breast density, the added risk of false positives from earlier screenings may be balanced by the benefits associated with earlier (breast cancer) detection in this group,” wrote study co-author Mahdi Fallah, M.D., Ph.D., who is affiliated with the Risk Adapted Prevention Group within the Division of Preventive Oncology at the German Cancer Research Center in Heidelberg, Germany, and colleagues.

(Editor’s note: For related content, see “Study Finds Disparities with Follow-Up After Incomplete Mammography Exams” and “Large Post-Mammography Study Shows Significant Racial and Ethnic Disparities with Breast Biopsy Delays.”)

Noting a mean 10-year cumulative breast cancer death risk of 0.154 percent for initiation of annual mammography screening at 40 years of age, the researchers still saw significant risk disparities between Black women (who would reach this risk threshold by the age of 34) and other populations (age 41 for Non-Hispanic White women and age 43 for Hispanic women, Asian/Pacific Islander women and American Indian women).

Fallah and authors maintained that a risk-adapted approach to age thresholds for mammography screening emphasizes health equity over equality and could help reduce breast cancer mortality while ensuring optimal allocation of health-care resources.

“Equality in the context of (breast cancer) screening means that everyone is screened from the same age regardless of risk level. On the other hand, equity or risk-adapted screening means that everyone is provided screening according to their individual risk level. We believe that a fair and risk-adapted screening program may also be associated with optimized resource allocation,” emphasized Fallah and colleagues.

In regard to study limitations, the authors acknowledged that reduced access to screening and treatment may have contributed to the higher mortality risks for Black women. They also noted that breast cancer mortality is affected by a variety of factors, ranging from breast density and quality of screening tests to types of treatment and genetic differences in tumors.