aacr.org/ | Wednesday, January 21, 2026 
What’s Behind the Increase in Cancer Cases Among Younger Adults?

When you hear the word “cancer,” the image of a young adult likely doesn’t spring to your mind, and for good reason: Historically and biologically, cancer has been a disease of aging. The human body—enduring, in the course of its duties, the slings and arrows of carcinogen exposure, stress, and plain old cellular incompetence—accumulates opportunity for cancer to emerge as time marches on. The default assumption that cancer is a disease of advanced age, however, has grown increasingly unreliable due to the sharp recent increase in cancer incidence among those under age 50. While increasing age remains a dominating driver across all cancer cases, the growing trend of early-onset cancers—up more than 15% since 2000—presents questions and challenges beyond the ongoing goal to improve diagnosis, intervention, and treatments. That’s why, in 2025, the American Association for Cancer Research (AACR) organized a meeting to address this emerging challenge head-on. At the AACR Special Conference in Cancer Research: The Rise in Early-onset Cancers—Knowledge Gaps and Research Opportunities, researchers from around the world gathered to share their findings on what may be driving the increase as the first step in developing strategies to counteract it…Read more