Breast cancer incidence is rising among U.S. women under 50, according to new research published in JAMA Network Open [1].
This includes elevated diagnosis rates for non-Hispanic Black women in their 20s and 30s, before the disease is even on their radar. Experts believe the data underscore the importance of better understanding risk factors for younger patient populations, along with targeted prevention strategies for at-risk groups.
“For most women, regular breast cancer screening does not begin until at least age 40, so younger women diagnosed with breast cancer tend to have later-stage tumors, when the disease is more advanced and more difficult to treat,” senior author Adetunji T. Toriola, MD, PhD, a professor of surgery at the Washington University School of Medicine in St. Louis, said in an announcement. “This research offers a way to begin identifying the factors driving these increasing rates, with the goal of finding ways to slow or reverse them.”
For the analysis, researchers used data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results Program, spanning 2000 to 2019. They targeted all women ages 20 to 49 with primary invasive breast cancer, turning up a total of nearly 218,000 cases. In 2000, the incidence of breast cancer for women before 50 was about 64 cases per 100,000. The rate increases steadily (by about 0.24% annually) but took a sharp, unexplained turn in 2016 (to 3.76%). By 2019, the rate had jumped to 74 breast cancer cases per 100,000.
Toriola et al. noted that the uptick was almost entirely due to an increase in tumors that are estrogen-receptor positive, where proteins on the surface bind to estrogen and fuel growth. Meanwhile, the incidence of tumors without the estrogen receptor dropped during the 20-year period. Black women also saw higher incidence rates, with a 53% increased risk of breast cancer in their 20s compared to white women of the same age. Same for in their 30s, though the greater risk fell to 15% and then dropped to bellow the rate of white women in their 40s.
“We are hopeful this study will offer clues to prevention strategies that will be effective in younger women, especially younger Black women, who are at particularly high risk of developing breast cancer before age 40,” Toriola said in the announcement.
Read much more in JAMA at the link below.
Marty Stempniak has covered healthcare since 2012, with his byline appearing in the American Hospital Association's member magazine, Modern Healthcare and McKnight's. Prior to that, he wrote about village government and local business for his hometown newspaper in Oak Park, Illinois. He won a Peter Lisagor and Gold EXCEL awards in 2017 for his coverage of the opioid epidemic.