Rectal Cancer Mortality Rising Faster Than Colon Cancer Among Younger U.S. Adults

A study set to be presented at Digestive Disease Week 2026 in Chicago shows that rectal cancer mortality rates are rising two to three times faster than colon cancer rates among U.S. adults aged 20 to 44. The research, based on Centers for Disease Control and Prevention death records from 1999 to 2023, used a machine learning model to project trends.

For adults aged 35 to 44, rectal cancer mortality is projected to increase through 2035, according to the study. The mortality gap between rectal and colon cancer is widening across demographics, with the steepest increases among Hispanic adults and residents of Western states.

Younger patients often experience diagnostic delays, with an average of seven months before starting treatment, compared to one month for older adults. Primary care providers sometimes attribute symptoms like rectal bleeding or changes in bowel habits to benign conditions such as hemorrhoids.

“Colorectal cancer is no longer considered predominantly a disease of older adults.”

Mythili Menon Pathiyil, a gastroenterology fellow at SUNY Upstate Medical University and lead author of the study, stated that rectal cancer is driving much of the increase in colorectal cancers. Rachel Gordon, a New York-based colorectal and general surgeon at Episcopal Health Services, noted that young people are diagnosed at younger ages and often at more advanced stages.

Gordon, who was not involved in the study, mentioned potential roles of lifestyle, environmental exposures, diet, and changes in the gut microbiome.