American Cancer Society Says Colorectal Cancer Tops Deaths Under 50

A study by the American Cancer Society published Thursday in the Journal of the American Medical Association found colorectal cancer became the leading cause of cancer death among U.S. adults under 50 in 2023, based on analysis of nearly 1.3 million cancer deaths from 1990 through 2023, the researchers reported.

The finding matters because overall cancer mortality for people under 50 fell 44% from 1990 to 2023 while colorectal cancer death rates climbed about 1% annually since 2005, making it the only top-five cancer to increase, the study found.

Rebecca Siegel, senior scientific director of surveillance research at the American Cancer Society and lead author of the study, said it "is absolutely an outlier" and urged clinicians and young adults to prioritize screening and evaluation of symptoms, she said.

The researchers reported that colorectal cancer rose from the fifth-leading cause of cancer death in people under 50 in 1990 to the first in 2023, the study said.

Researchers and clinicians said they will pursue studies of potential causes such as rising obesity, declining physical activity, changes in the gut microbiome and diets high in ultraprocessed foods while urging adherence to U.S. Preventive Services Task Force guidance to begin screening at age 45 for average-risk adults.