Cancer deaths are falling among young Americans — except for one terrifying outlier.
Over the past 30 years, it has surged to become the top cancer killer of people under 50, overtaking breast, lung and brain cancers, as well as leukemia, a new analysis found.
“It is clear that this can no longer be called an old person’s disease,” Dr. Ahmedin Jemal, a senior author of the study and a top official at the American Cancer Society, said in a statement.
In the study, researchers analyzed more than 1.2 million deaths and found that overall cancer mortality in Americans under 50 dropped 44% between 1990 and 2023.
The decline was driven by sharp drops in four of the five leading cancer killers, which fell by as much as 6% annually.
Only one increased: colorectal cancer, which rose 1.1% each year over the past three decades, climbing from the fifth most common cancer death to first place.
“The steady rise in colorectal deaths under 50 is even more alarming compared to the dramatic declines for lung and breast, even as breast cancer incidence is climbing,” said Rebecca Siegel, senior scientific director of surveillance research at the American Cancer Society and lead author of the report.
The findings come as overall colorectal cancer rates in young Americans continue to climb, even as cases in older adults — the group historically most affected — have been falling for years.
“While we await answers for why colorectal cancer rates are up, lives can be saved now through symptom awareness and destigmatization and more screening uptake, as 3 in 4 people under 50 are diagnosed with advanced disease,” Siegel said.
Colonoscopies are considered the gold standard screening method for colorectal cancer, letting doctors detect disease and remove precancerous growths in one procedure.
While average-risk Americans were traditionally advised to start screening at 50, the American Cancer Society lowered its recommended starting age to 45 in 2018 amid the surge in cases among young people. Other major health bodies followed suit in subsequent years.
Now, doctors are urging young people to talk with relatives about their colonoscopy results.
“There are no risk factors that have been definitively concluded for early onset of colorectal cancer,” said Dr. Christine Molmenti, cancer epidemiologist and co-director of the Northwell Health Early-Onset Cancer Program, who was not involved in the study.
While research has suggested potential links between the disease and lifestyle factors such as ultra-processed food, obesity, smoking, alcohol and sugary drinks, many young colorectal cancer patients don’t fit that profile, she explained.
“They say they’re healthy. They say they eat well, and that they are generally fit and active,” Molmenti said. “Without a real firm risk factor, the best tool we have and the best strategy for early onset colorectal cancer prevention is family history.”
Scientists estimate that 16% of early-onset colorectal cancer cases are due to a genetic or inherited condition that increases a person’s risk.
“That’s 16% of the pie,” Molmenti said. “Then, 14% are due to the family history of colorectal cancer by a first-degree relative in their family.”
The remaining 70% is considered sporadic, but Molmenti noted that recent investigations have found an 18% rate of advanced polyps in first-degree relatives of early-onset cancer patients.
“That means if someone knows what their family’s colonoscopy results are — not for cancer, but for polyps — it could be lifesaving,” Molmenti said. “They could be diagnosed earlier or the cancer could be detected earlier because the guidelines for screening for colorectal cancer or advanced polyps is the same.”
People with a close family history of colon cancer or other risk factors, such as advanced polyps, are often advised to start screening by age 35 — or 10 years earlier than the youngest affected relative was diagnosed.
“There are almost more than 19,000,000 colonoscopies [performed annually] in the US today, and 2 to 10% of those [find] advanced polyps,” Molmenti said. “So those patients diagnosed with advanced polyps, especially if you’re 45, should be telling your brothers and sisters if you have them to get screened at 35.”
In 2026 alone, the American Cancer Society projects 108,860 new colon cancer cases and 49,990 new rectal cancer cases will be diagnosed in the US.
An estimated 55,230 Americans will die from the two diseases combined.
