Rising rates of colorectal cancer found in nearly all age groups

U.S. colorectal cancer incidence, which had declined for decades, has begun rising again and the increase is no longer limited to adults under 50. An analysis of National Cancer Institute data found the age-adjusted rate fell from 55.2 cases per 100,000 people in 2000 to 36.7 in 2022, then rose to 38.3 in 2023. Rates increased across age groups through 65-69. The sharpest rise was among people aged 45-49, up 12.76% annually from 2019 to 2023, likely in part because screening recommendations now start at 45. But rising rates among 65-69-year-olds and a plateau among 70-74-year-olds are harder to explain, since screening is common in those groups. The increase persisted even after pandemic years were excluded.

Researchers suggest a birth-cohort effect may be bringing higher risks among people born in the 1960s and later into older age, but the factors behind the trend remain unknown. They are investigating environmental chemical exposures, while emphasizing that increased diagnoses across a large, aging population could strain treatment and survivorship services. Screening remains the strongest way to find cancer early and prevent deaths: average-risk adults are advised to begin at 45 and continue through 75, with colonoscopy and stool- or blood-based tests among the options to discuss with a clinician. People under 45 should seek medical advice for symptoms such as blood in stool, changed bowel habits, or unexplained weight loss.