Colorectal cancer is now the leading cause of cancer death in people under 50
Colorectal cancer is now the leading cause of cancer death among people under the age of 50 in the United States, according to a study published Thursday in the Journal of the American Medical Association.
Colorectal cancer death rates in this age group have increased by 1% each year since 2005, in stark contrast to the broader trend: Overall, cancer death rates among people under 50 have fallen 44% since 1990. And among the five most common causes of cancer death among people under 50, colorectal cancer deaths were the only one to increase.
“It’s absolutely an outlier,” said Rebecca Siegel, senior scientific director of surveillance research at the American Cancer Society, who led the study.
Although most cases of colorectal cancer still occur in people over the age of 50, the number of people diagnosed with the disease in their 20s, 30s, or 40s has increased dramatically in recent decades. In light of this trend, researchers previously predicted that colorectal cancer deaths would take the top spot in cancer deaths among people under 50 by 2030.
He claimed this spot seven years earlier than expected, in 2023, according to the new study.
Siegel and colleagues analyzed National Cancer Institute data on nearly 1.3 million people under 50 who died of cancer between 1990 and 2023. In 1990, colorectal cancer was the fifth leading cause of cancer death among all people under 50.
In contrast, deaths from the other four leading causes of cancer death have declined. Lung cancer deaths in the group fell from first to fourth, declining nearly 6% annually from 2014 to 2023. Leukemia deaths fell from third in 1990 to fifth in 2023 and declined nearly 2.5% each year from 2014 to 2023.
Breast cancer remained the second leading cause of cancer deaths overall and the leading cause among women, but deaths declined by 1.4% per year between 2014 and 2023.
The decline in other cancer-related deaths does not fully explain why colorectal cancer deaths are now the leading cause of cancer deaths among younger men and women, said Dr. Andrew Chan, chief of the clinical and translational epidemiology unit at Massachusetts General Brigham in Boston.
“We have been successful in reducing deaths from other types of cancer, which only amplifies the increase in colorectal cancer deaths, but the rapid increase in colorectal cancer deaths among people under 50 is quite remarkable,” said Chan, who was not involved in the study.
The increases “truly outweigh the declines in death rates from other types of cancer,” he added.
Even though cases of colorectal cancer are increasing, that alone cannot explain why mortality rates from the disease are increasing among young people, Chan said. Indeed, the study found that although cases of breast cancer and leukemia were increasing, mortality rates were decreasing.
While the overall decline in cancer-related deaths is good news, the findings starkly highlight the worrying increase in colorectal cancer deaths among young people, said Dr. Folasade May, associate professor of medicine in the Vatche and Tamar Manoukian Division of Digestive Diseases at UCLA.
“It’s good news and bad news, and for a doctor who specializes in colorectal cancer, it’s a horror story,” said May, who was not involved in the study.
It’s not clear why rates of colorectal cancer are increasing among young people. About 20% of colorectal cancer cases are diagnosed in people aged 54 or younger, double the rate in 1995, according to a 2025 report from the American Cancer Society.
The trend is clear, but the cause is still poorly understood, said Siegel, the study author.
Research suggests that rising obesity rates and declines in physical activity, changes to the gut microbiome, and diets high in ultra-processed foods, which have become more common since the 1980s, may be to blame.
But “other factors are believed to be at play and are not the only reason for this increase,” Siegel said.
It’s crucial for young people to understand that their risk of colorectal cancer has increased and to get screened, especially if they have symptoms, such as blood in their stool or stomach cramps, Siegel said. The U.S. Preventive Services Task Force recommends universal screening starting at age 45 and earlier for those at high risk.
“Half of people diagnosed before age 50 are ages 45 to 49, so they are eligible for screening,” Siegel said.
