Breast cancer is quietly showing up more often in some groups of women, especially younger adults, even as overall death rates keep falling. That mix of good and bad news has oncologists and breast-health clinics in St. Louis watching screening habits and risk patterns more closely. The percentage increase is small, but researchers say it matters because it affects women who often sit outside routine screening guidelines.
What the data show
The Centers for Disease Control and Prevention found that breast cancer incidence among women younger than 45 rose an average of 0.7% per year from 2001 through 2022, with 27,136 new cases reported in this age group in 2022, even as death rates declined. According to the CDC, increases occurred across racial and ethnic groups but varied in pace and magnitude. Local outlet KSDK flagged the figures for St. Louis viewers on April 13, 2026, putting a local lens on a national trend.
Why the rises matter
The American Cancer Society reports that overall breast cancer incidence climbed about 1% per year from 2012 to 2021, with women under 50 seeing a steeper rise of roughly 1.4% annually. Most of the extra cases were classified as localized, hormone receptor positive tumors. As detailed by the American Cancer Society, better detection and more effective treatment have driven a long-term drop in mortality, even as more cancers are being picked up.
New studies add detail
A long-range analysis by Washington University researchers, published in JAMA Network Open, found that the strongest increases among women aged 20 to 49 came after 2016 and that certain tumor subtypes and early stage diagnoses account for much of the growth. The National Cancer Institute has also pointed to rising obesity, changing reproductive patterns, increased surveillance and coding shifts as possible contributors and has estimated several thousand additional early onset breast cancers in recent years, according to the NCI.
Local doctors weigh in
In St. Louis, specialists say the trend is a reason to act, not to panic. Adetunji Toriola of Washington University and Siteman Cancer Center told researchers at a recent meeting that mortality among younger women has fallen, underscoring how advances in treatment and access to care are making a difference. His presentation was summarized by the AACR. In response, Siteman and community clinics are leaning into targeted outreach and risk assessment rather than a one size fits all approach to screening younger patients.
Screening and next steps
For most people, the practical takeaway is to understand personal risk and stick with recommended screening. The U.S. Preventive Services Task Force calls for mammograms every other year for women ages 40 to 74. The CDC also urges people to learn the signs of breast changes and to seek care for persistent lumps or other symptoms, and local partners run mobile mammography programs to reach patients who face barriers to care. See the USPSTF and local screening partners for details. Clinicians also encourage patients with a family history or other risk factors to talk through whether earlier or more frequent screening makes sense.
