High Prevalence of Adenomatous Polyps in Alaska Native People Aged 40-49 years

Although colorectal cancer occurs earlier in life and at twice the frequency in Alaska Native (AN) people compared with the general population, the colorectal polyp burden in this group has not been quantified. In addition, an appropriate age for initial screening in ANs has not been defined.

A retrospective chart review of 766 AN people who had screening colonoscopy from 2015 to 2016 was performed. The polyp burden in patients aged 40-49 y was compared with that in those aged 50-59 y in both the AN and the general US populations.

In total, 345 adenomas were removed: 121 (35%) from 40- to 49-year-olds and 224 (65%) from 50- to 59-year-olds. Twenty-six percent of AN people aged 40 y to 49 y and 40% of AN people aged 50 to 59 y had at least one adenoma. Low- and high-risk adenomas were significantly less frequent in the younger group (22% versus 29%, P = 0.048; 9.2% versus 15%, P = 0.035; respectively). Advanced adenomas were also less frequent in the younger group, although not statistically significant. Polyp histology, size, location, and morphology did not differ significantly between groups.

The adenoma and advanced adenoma prevalence in 40- to 49-year-old AN people is high, suggesting colorectal cancer screening should begin at age 40 y in ANs.