The Rising Crisis of Colorectal Cancer in Young Adults: Warning Signs, Rising Deaths, and What People can Do

Colorectal cancer is becoming an increasingly urgent health concern for younger adults, with rising diagnoses and death rates among people under 50 prompting warnings from medical experts and public health officials. Once considered primarily a disease of older age, colorectal cancer now ranks as a leading cause of cancer-related death in younger populations, driven in part by a sharp increase in rectal cancer cases.

According to a 2024 report from the American Cancer Society cited by NBC News, colorectal cancer is now the leading cause of cancer-related death among men aged 20 to 49 in the United States. For women in the same age group, it is second only to breast cancer. This marks a significant shift from the 1990s, when colorectal cancer ranked fourth for both men and women in that age range.

The trend is not limited to the United States. Similar increases in colorectal cancer diagnoses among adults under 50 have been documented in Canada, Australia, New Zealand, and parts of Asia and Europe. In the U.S., diagnoses among those under 50 have been rising by 1% to 2% annually in recent years, even as overall colorectal cancer rates have declined in the broader population.

Rectal cancer, in particular, is contributing disproportionately to this rise. A study led by Mythili Menon Pathiyil, a gastroenterology fellow at SUNY Upstate Medical University, found that the rate of rectal cancer is increasing two to three times faster than colon cancer among younger adults. If current trends continue, rectal cancer deaths could exceed colon cancer deaths in people under 50 by 2035.

Dr. Ben Schlechter, a gastrointestinal medical oncologist at Dana-Farber Cancer Institute in Boston, described the situation as a medical crisis that should not be ignored. He emphasized that the rapid increase in cases among millennials and young adults is confounding scientists who are working to understand the underlying causes.

While the exact reasons for the rise remain unclear, researchers are investigating a range of possible factors, including lifestyle influences and health conditions associated with colorectal cancer. Dr. David Liska, director of the Center for Young-Onset Colorectal Cancer at the Cleveland Clinic, noted that more research is needed to determine what is driving the increase in early-onset cases.

To help address delayed diagnoses, a 2023 study by the National Cancer Institute identified four warning signs of colorectal cancer in younger adults that appear more frequently in the months to years before diagnosis: abdominal pain, rectal bleeding, diarrhea, and iron deficiency anemia. The study, which analyzed insurance claims data from over 5,000 people diagnosed with early-onset colorectal cancer and more than 22,000 controls, found that having just one of these signs was associated with nearly twice the likelihood of being diagnosed with the disease. Having three or more signs increased the likelihood by six times.

Yin Cao, Sc.D., senior investigator on the study from the Washington University School of Medicine in St. Louis, stressed that colorectal cancer is no longer a disease exclusive to older populations. She urged younger adults not to delay seeking medical care if they experience any of these symptoms, and called on clinicians to remain alert to the possibility of colorectal cancer in younger patients.

The American Cancer Society estimates that 158,850 new colorectal cancers will be diagnosed in the United States in 2026, with approximately 55,230 deaths attributed to the disease. Nearly a third of those deaths are expected to occur in people under the age of 65.

As incidence continues to rise among younger adults, public health efforts are increasingly focused on raising awareness, improving symptom recognition, and encouraging timely medical evaluation. Experts agree that while the causes of the trend are not yet fully understood, early detection through symptom awareness remains a critical tool in improving outcomes.