Our goal was to inform endoscopist practice by exploring how the odds of advanced neoplasia in the right and left colon differ between men and women with and without prior positive stool tests.
Our primary outcome was advanced lesions (advanced adenomas, advanced serrated polyps, and/or colorectal cancer) found during colonoscopy. We used logistic regression to compare adjusted outcome odds by colon location (left or right), patient sex, and screening cohort.
Stool-test+ patients had higher odds for advanced lesions than colonoscopy-only patients throughout the colon, regardless of sex. While colonoscopy-only men had significantly higher odds of advanced lesions in the right vs. left colon (OR: 1.87 [1.75–1.99]), the odds of advanced lesions in mt-sDNA+ and FIT+ men did not differ significantly by colon location. As a result, compared to colonoscopy-only men, the increase in advanced lesion odds in stool-test+ men is significantly lower in the right vs. left colon (mt-sDNA+: OR: 0.63 [0.44–0.90]; FIT+; OR: 0.50 [0.30–0.83]). In stool-test+ women there was no significant difference in the degree of increase in advanced lesion odds in the right vs. left colon.
Positive stool tests are associated with increased left- and right-sided advanced polyp yield in men and women at colonoscopy. However, stool-test-positive men had a significantly higher increase of advanced lesions in the left colon, whereas we found no such differences in women.