Changing colon cancer screening guidelines to age 45: Has it made a difference?

A concerning increase in early-onset colorectal cancer led to guideline changes in 2018 by the American Cancer Society to lower the age for initial colorectal cancer screening from 50 to 45 years of age. Although this would be expected to result in increased screening rates and subsequent earlier detection of colorectal cancer, the effect of this guideline change at a national level is not yet fully understood.

Using the National Cancer Database, we identified patients newly targeted for screening (age 45-49 years) diagnosed with colon cancer in either 2017 (early cohort) or 2019 (late cohort). The relationship between time period and stage of disease at presentation was examined by univariate analysis and in a multivariable logistic regression model.

In total, 5,479 patients met inclusion criteria. The median age at diagnosis did not differ between patients in the late and early cohorts (47 years for both cohorts, P = .41). Patients in the late and early cohorts had equal odds of having stage III-IV disease (odds ratio for late cohort to early cohort, 1.05, 95% confidence interval, 0.94-1.17), and patients in the late cohort showed slightly increased odds of having higher T-stage (pT3 or pT4) disease (odds ratio, 1.20, 95% confidence interval, 1.05-1.35).

Despite recommendations of earlier initial colorectal cancer screening, a clinically meaningful earlier shift in colon cancer stage was not observed in patients newly targeted for screening. Further studies will be needed to assess uptake of these recommendations by providers and patients and identify areas of improvement.