New Clues Shed Light on Rising Colon Cancer in Young Adults

WHO:

Fast Company - Researchers from the University of Chicago conducted the study on colorectal cancer incidence; lead author Caitlin Murphy is a professor of pediatrics and public health sciences at the University of Chicago.

Fast Company - The University of Chicago researchers plan to work with a toxicologist from Emory University to investigate environmental chemical exposures.

The Boston Globe - Researchers from Dana-Farber Cancer Institute, Mass General Brigham, and the Broad Institute conducted the tumor study.

The Boston Globe - Senior authors included Ana Anderson, core faculty member of the Gene Lay Institute of Immunology and Inflammation at Brigham and Women’s Hospital, and Dr. Kimmie Ng, director of Dana-Farber Cancer Institute’s Young-Onset Colorectal Cancer Center.

The Boston Globe - Dr. John Paul Shen, an associate professor of gastrointestinal medical oncology at the University of Texas MD Anderson Cancer Center, was not involved in the study. Dr. Christina Annunziata is senior vice president of extramural discovery science at the American Cancer Society.

WHAT:

Fast Company - A University of Chicago study published in NEJM Evidence found that US colorectal cancer incidence rose for the first time in more than 20 years: the age-adjusted rate increased from 36.7 per 100,000 people in 2022 to 38.3 in 2023. The rate was 55.2 in 2000.

Fast Company - Incidence among people aged 45–49 increased nearly 13% from 2019 to 2023, the sharpest rise of any age group. The article says increased screening may explain the rise in this group.

Fast Company - Incidence is also rising among adults aged 65–69, although about 80% of this group is up to date with screening.

Fast Company - Colorectal cancer is the second leading cause of cancer-related deaths in the United States. An estimate cited from the American Cancer Institute says nearly 160,000 Americans will be diagnosed with colorectal cancer this year, including colon and rectal cancer.

The Boston Globe - A study published in Nature Medicine analyzed 189 tumors from people in their 20s to 90s, including 54 patients diagnosed before age 50, and analyzed more than 850,000 cells. Researchers described it as the largest dataset to date for colorectal cancer and one with the highest number of young patients.

The Boston Globe - Tumors in younger patients appeared to contain a higher proportion of stromal cells, which provide connective and structural support. The study also found differences in gene expression in younger patients’ tumors.

The Boston Globe - In the United States, colorectal cancer rates among people younger than 50 rose nearly 3% per year from 2013 through 2022; it is now the leading cause of cancer death in that age group.

WHERE:

Fast Company - The incidence findings concern the United States.

The Boston Globe - The tumor research involved Dana-Farber Cancer Institute, Mass General Brigham, and the Broad Institute; the cancer-rate statistics concern the United States.

WHEN:

Fast Company - The US Preventive Services Task Force lowered the recommended age to begin screening from 50 to 45 in 2021.

The Boston Globe - The study examined tumors from patients diagnosed across a range of ages; its reported US incidence trend covers 2013 through 2022.

WHY:

Fast Company - The researchers said unknown risk factors may be offsetting previous gains from screening; the underlying causes of rising incidence remain unclear.

The Boston Globe - Researchers are investigating why colorectal cancer is increasing among younger people. Diet, ultra-processed foods, and other lifestyle and environmental factors have been linked to risk, but the study examined tumor biology for additional clues.

HOW:

Fast Company - Researchers plan to measure thousands of environmental exposures, select chemicals for further study, and test them on organoids—specialized models that can grow colon tissue in a dish.

The Boston Globe - Researchers examined tumor tissue at the cellular level and compared cell composition and gene expression by patient age.

(UPDATED October 29, 2026 20:06 UTC)

Colorectal cancer incidence in the United States rose for the first time in more than 20 years, with the age-adjusted rate increasing from 36.7 per 100,000 people in 2022 to 38.3 in 2023. A separate analysis of 189 tumors found that younger patients’ tumors had more connective-tissue cells and differences in gene activity, as colorectal cancer rates among Americans under 50 have been climbing and the disease is now the leading cause of cancer death in that age group. The reasons for the increase remain unclear, and researchers are investigating tumor biology and environmental exposures for clues.