Risk-Stratified CRC Screening Using Fecal Immunochemical Test and Stool DNA
By

Risk-Stratified CRC Screening Using Fecal Immunochemical Test and Stool DNA

Douglas K. Rex, MD, MASGE, reviewing Xu J, et al. Clin Gastroenterol Hepatol 2022 Sep 13.

This is a post hoc analysis of a risk-stratification screening strategy based on the Asia-Pacific Colorectal Screening (APCS) scoring system. This score ranks patients as high, moderate, or low risk for colorectal cancer (CRC) or advanced neoplasia based on age, sex, family history of CRC in a first-degree relative, and smoking status.

A total of 2240 patients underwent colonoscopy, of whom 38.8% were classified as high risk according to the APCS scoring system and, therefore, would go directly to colonoscopy. With the remaining low- and moderate-risk patients, investigators evaluated the performance of a fecal immunochemical test (FIT) at cutoffs of 20 µg Hb/g stool and 4.4 µg Hb/g stool and a stool DNA test developed in China.

The high-risk patients were more likely to have advanced neoplasia (20.1% vs 12.2%). The combined sensitivity of the APCS score with the stool DNA test for advanced neoplasms was 73.5%, which was higher than the APCS score combined with FIT at both the 20 µg cutoff (62.8% sensitivity) and the 4.4 µg cutoff (68% sensitivity). 

The combination of this specific DNA test plus FIT did not alter test specificity. All the strategies had high sensitivity for cancer: 95.2% for the APCS score plus the stool DNA test, 90.5% for the APCS score plus FIT at 4.4 µg, and 88.1% for the APCS score plus FIT at 20 µg.

The strategy of the APCS score plus the stool DNA test reduced overall colonoscopy use by 53%.

Douglas K. Rex, MD, FASGE

COMMENT

This study shows that stool DNA tests may perform somewhat differently than the test commonly used in the U.S. For example, this test increases sensitivity for advanced neoplasia without negatively impacting specificity, compared with FIT. 

This risk-stratified approach is seldom used in the U.S. but merits consideration when colonoscopy resources are limited. 

In the U.S., where colonoscopy resources are usually not limited, I still favor sequential offers of screening, utilizing colonoscopy first (which does not give up detection of more than one-quarter of advanced neoplasms, compared with the strategies used in this study) and noninvasive tests for patients who decline colonoscopy.

Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.

CITATION(S)

Xu J, Rong L, Gu F, et al. Asia-Pacific Colorectal Screening Score combined with stool DNA test improves the detection rate for colorectal advanced neoplasms. Clin Gastroenterol Hepatol 2022 Sep 13. (Epub ahead of print) (https://doi.org/10.1016/j.cgh.2022.09.002)

Related Posts

Scroll to Top