Federal cancer screening guidelines recommend that people with an average risk for colorectal cancer begin screening at age 45. Vadym Terelyuk / / iStockphotoShareAdd NBC News to GoogleMarch 2, 2026, 3:39 PM ESTBy Erika EdwardsListen to this article with a free account00:0000:00A rise in rectal cancer rates is driving an increase in colorectal cancer diagnoses in people younger than 65, according to a report published Monday from the American Cancer Society. Colorectal cancer rates in people under 65 are surging, with nearly half (45%) of new diagnoses occurring in this age group, up from 27% in 1995. At the same time, colorectal cancer rates are falling in people 65 and older. Rectal cancers on their own, however, are rising in all adults, and now account for nearly one-third of all colorectal cancer diagnoses, up from 27% in the mid-2000s, the report found. Between 2018 and 2022, rectal cancer diagnoses rose by 1% each year in all age groups.