Trends in Breast Cancer Incidence, by Race, Ethnicity, and Age Among Women Aged ≥20 Years - United States, 1999-2018

Abstract

Breast cancer is commonly diagnosed among women, accounting for approximately 30% of all cancer cases reported among women.* A slight annual increase in breast cancer incidence occurred in the United States during 2013-2017 (1). To examine trends in breast cancer incidence among women aged ≥20 years by race/ethnicity and age, CDC analyzed data from U.S. Cancer Statistics (USCS) during 1999-2018. Overall, breast cancer incidence rates among women decreased an average of 0.3% per year, decreasing 2.1% per year during 1999-2004 and increasing 0.3% per year during 2004-2018. Incidence increased among non-Hispanic Asian or Pacific Islander women and women aged 20-39 years and decreased among non-Hispanic White women and women aged 50-64 and ≥75 years. The U.S. Preventive Services Task Force currently recommends biennial screening mammography for women aged 50-74 years (2). These findings suggest that women aged 20-49 years might benefit from discussing potential breast cancer risk and ways to reduce risk with their health care providers. Further examination of breast cancer trends by demographic characteristics might help tailor breast cancer prevention and control programs to address state- or county-level incidence rates^† and help prevent health disparities.

FIGURE 1

Trends in breast cancer incidence among women aged ≥20 years, by race/ethnicity^, ─ United States, 1999–2018 Abbreviations: AAPC = average annual percent change; AI/AN = American Indian or Alaska Native; A/PI = Asian or Pacific Islander. * Trends were estimated using joinpoint regression, with a maximum of three joinpoints (up to four-line segments) allowed; the year at which slopes changed could vary by age and race/ethnicity. Data displayed are the modeled age-adjusted rates. ^† Cancer incidence data were compiled from cancer registries that meet U.S. Cancer Statistics data quality criteria (https://www.cdc.gov/cancer/npcr/standards.htm), covering 97% of the U.S. population. ^§ Mutually exclusive racial/ethnic groups are based on information about race/ethnicity that was collected separately and combined for this report. Race/ethnicity were grouped as non-Hispanic AI/AN, non-Hispanic A/PI, non-Hispanic Black, Hispanic, and non-Hispanic White. Hispanic persons can be any race. Data are not presented for those with unknown or other race or unknown ethnicity. ^¶ AAPC was significantly different from zero at the α = 0.05 level for non-Hispanic A/PI and non-Hispanic White persons.

FIGURE 2

Average annual percent change in breast cancer incidence among women aged ≥20 years by race/ethnicity and age group ─ United States, 1999–2018 Abbreviations: AAPC = average annual percent change; AI/AN = American Indian or Alaska Native; A/PI = Asian or Pacific Islander. * AAPC is the weighted average of the annual percent change during 1999–2018. To determine whether AAPC was significantly different from zero, a t-test was used if the joinpoint regression model had zero joinpoints, and a z-test was used if the joinpoint regression model had ≥1 joinpoint. ^† Cancer incidence data were compiled from cancer registries that meet U.S. Cancer Statistics data quality criteria (https://www.cdc.gov/cancer/npcr/standards.htm), covering 97% of the U.S. population. ^§ Mutually exclusive racial/ethnic groups are based on information about race/ethnicity that was collected separately and combined for this report. Race/ethnicity were grouped as non-Hispanic AI/AN, non-Hispanic A/PI, non-Hispanic Black, Hispanic, and non-Hispanic White. Hispanic persons can be any race. Data are not presented for those with unknown or other race or unknown ethnicity.