A simplified multitarget stool test for colorectal cancer and advanced precancerous lesion detection

Multitarget stool tests are approved for colorectal cancer (CRC) screening. Here we developed a multitarget stool test based on the fecal immunochemical test (FIT) and two (NDRG4 and SDC2) DNA methylation markers with a simple calling algorithm.

FIT, quantitative methylation-specific PCR for NDRG4 and SDC2 were performed for each participant. A score of either 0, 1 or 2 was assigned to each marker as negative, weak positive and positive. A positive test score was called when the score sum for the three biomarkers was at least 2.

A total of 120 CRC, 23 advanced precancerous lesions (APL) and 308 negative controls (including 59 non-advanced neoplasia, 26 polyps smaller than 10 mm in size and 223 negative colonoscopy) from two hospitals were enrolled. Age-dependent cut-off values were used for FIT and NDRG4 as their levels were positively correlated with age. Sensitivities with the multitarget stool test for CRC and APL were 90.0 % and 65.2 %, respectively, while specificities for participants with negative colonoscopy and absent of advanced neoplasia were 91.0 % and 90.9 %, respectively. We observed a general decline in specificity with more advanced age, which was significantly mitigated by the age-dependent cut-off values.

The simplified multitarget stool test utilizing age-dependent cut-off values demonstrated promising performance for CRC screening across age groups in the Chinese population.