Cosmos Study

DNA Stool Tests for Colorectal Cancer Screening Growing in Popularity, Especially for Patients Under Age 50

May 14, 2024

Team A:Kersten Bartelt, RNAlex Piff

Team B:Steve Allen, MDJeff Trinkl, MDEric BarkleyTed Stamp

Key Findings

The use of DNA stool tests for colorectal cancer screening has increased more than nine-fold since 2018, rising from 3% of screenings in the first quarter of 2018 to 31% of screenings in the fourth quarter of 2023.
Patients aged 45 to 49 used DNA stool testing for their colorectal cancer screening at a higher rate than those aged 50 to 55.
Patients with the highest social vulnerability index had lower rates of DNA stool testing compared to those with less social vulnerability, though the use among each group has increased.

In a previous study, we highlighted an increase in colorectal cancer screenings following an expansion of guidelines.¹ Patients have a variety of screening methods to choose from, including stool-based tests such as DNA stool tests and fecal occult blood tests, as well as imaging procedures like colonoscopy and sigmoidoscopy.²

We studied 1,422,099 first-time colorectal cancer screenings conducted by colonoscopy or DNA stool test between 2018 and 2023. We aimed to understand how the proportion of each method has evolved over time. In early 2018, colonoscopies accounted for 96% of colorectal cancer screenings. However, this proportion has gradually decreased, dropping below 70% of screenings in the third quarter of 2023, as seen in Figure 1. Conversely, the use of DNA stool tests has been on the rise, with a significant increase in the second quarter of 2020 and a continued upward trajectory to 31% of screenings in the fourth quarter of 2023.

Figure 1

Colorectal Cancer Screening Trends by Method

Figure 1. The percentage of colorectal cancer screenings completed with a DNA stool test and colonoscopy.

We wanted to understand whether the proportions of screening types had changed across subpopulations over the same period. We stratified the data by age, social vulnerability, and insurance coverage. We found that DNA stool testing has increased across all subpopulations.

In May 2021, the U.S. Preventative Services Task Force (USPSTF) expanded its colorectal cancer screening recommendation to include all adults aged 45 to 49.² Subsequently, the use of DNA stool tests for this group increased from 10% of screenings in the second quarter of 2021 to 22% of screenings in the fourth quarter of that same year. By the end of 2023, nearly a third of colorectal cancer screenings were performed by DNA stool test for this population. For patients aged 50 to 55, a large increase in DNA stool testing was observed during the second quarter of 2020. In the following quarters, rates trended upward but remained slightly lower than the 45- to 49-year-old group.

Figure 2

Percentage of Screenings Using DNA Stool Testing by Age

Figure 2. The percentage of colorectal cancer screenings performed with a DNA stool test by age.

Across social vulnerability index quartiles, DNA stool testing has increased at a similar rate for those in the first through the third quartile. However, those in the fourth quartile, the most vulnerable, have continued to have the lowest percentage of their colorectal screenings completed using a DNA stool test.

Figure 3

Percentage of Screenings Using DNA Stool Testing by Social Vulnerability

Figure 3. The percentage of colorectal cancer screenings performed with a DNA stool test by social vulnerability index quartile.

We did not observe meaningful differences in the proportion of colorectal cancer screenings performed using a DNA stool test over time when stratified by patient sex or rural and urban classification.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 246 million patient records from 1,400 hospitals and more than 32,800 clinics from all 50 states and Lebanon. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson.

Exact Sciences, the manufacturer of the FDA-approved DNA stool test, Cologuard, is an Epic customer but was not involved in this study.

References

Fox B, Joyce B, Allen S, Sahakian S. Colorectal Cancer Screening Rates on the Rise Following Guideline Expansion. Epic Research. https://epicresearch.org/articles/colorectal-cancer-screening-rates-on-the-rise-following-guideline-expansion. Accessed on February 28, 2024.
U.S. Preventive Services Task Force. Colorectal cancer: screening. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/colorectal-cancer-screening. Accessed February 28, 2024.