Breast cancer death rates have slightly increased in women younger than 40, reversing a longstanding trend in mortality rate decreases, according to research findings published Feb. 9 in Radiology.
Researchers conducted a retrospective analysis of breast cancer mortality rates using data from the National Center for Health Statistics and from the National Cancer Institute's Surveillance, Epidemiology and End Results program. While mortality rates decreased significantly between 1989 and 2010, the trend stopped among women younger than 40.
After 2010, breast cancer mortality rates continued to fall yearly among women aged 40-79, but increased by 2.8 percent per year in women aged 20-29 and 0.3 percent per year in those aged 30-39, the findings showed. Additionally, researchers observed a slower decline in breast cancer death rates among women aged 70-79 between 2009-17, compared to previous years.
Distant-stage breast cancer rates have increased more than 4 percent annually among younger women since 2000, and likely contributed to the stop in declining mortality rates in this age group, according to the study.
"A possible contributor to the recent marked difference in breast cancer mortality trends is mammography use," the researchers said. "The known benefit of screening mammography that has contributed to the mortality decline among women aged at least 40 years is largely absent among women younger than 40."
Similarly, the 2009 guideline recommendations discouraged screening in older women, which may also be partially linked to the slower decline in breast cancer death rates among women aged 70-79.
To view the full findings, click here.