Incidence rates of some cancer types have risen in people under age 50

"This study provides a starting point for understanding which cancers are increasing among individuals under age 50," said lead investigator Meredith Shiels, Ph.D., of NIH's National Cancer Institute. "The causes of these increases are likely to be cancer specific, including cancer risk factors becoming more common at younger ages, changes in cancer screening or detection, and updates to clinical diagnosis or coding of cancers."

The study appeared May 8, 2025, in Cancer Discovery.

Researchers examined incidence and mortality trends for 33 cancer types, including incidence data for 2010-2019 from CDC's United States Cancer Statistics database, which includes cancer registry data that represent the entire U.S. population, and mortality data for 2010-2022 from national death certificate data. Data were analyzed in six age groups: three early-onset (15-29 years, 20-39 years, and 40-49 years) and three older-onset (50-59 years, 60-69 years, and 70-79 years).

Incidence of 14 of the 33 cancer types increased in at least one of the younger age groups. Incidence of nine of these 14 types also increased in at least one of the older age groups: female breast, colorectal, kidney, testicular, uterine, pancreatic, and three types of lymphoma. Although death rates did not increase in early-onset age groups for most of these cancers, researchers did observe concerning increases in rates of colorectal and uterine cancers deaths at younger ages.

Only five cancer types increased in incidence among one of the younger age groups but not among any of the older age groups: melanoma, cervical cancer, stomach cancer, myeloma, and cancers of the bones and joints.

To understand the magnitude of the increases in terms of absolute numbers, the researchers estimated how many additional people were diagnosed with early-onset cancers in 2019 compared with expected diagnoses based on rates in 2010. The largest absolute increases were seen for female breast cancer, with about 4,800 additional cases in 2019, followed by colorectal (2,100), kidney (1,800), uterine (1,200), and pancreatic cancers (500). Female breast, colorectal, kidney, and uterine cancers contributed to more than 80% of the additional early onset cancers in 2019.

The researchers speculated that risk factors such as increasing obesity may have contributed to some of the increases in early-onset cancer incidence in recent years. Changes in cancer screening guidelines, advances in imaging technologies, and increased surveillance of high-risk individuals may also have led to earlier cancer diagnoses, potentially contributing to rising rates among younger age groups.

To more fully understand and address these increasing rates, the authors said that future studies should examine trends in early-onset cancers across demographics and geography in the U.S. and internationally. Additional research is also needed to better understand the risk factors that are particularly relevant to younger people.