In a side-by-side comparison, a noninvasive, multitarget stool DNA test proved to be more sensitive than a fecal immunochemical test (FIT). This result, published March 19 in the New England Journal of Medicine, suggests that the DNA test, which includes quantitative molecular assays for genetic abnormalities related to cancer, could significantly improve the effectiveness of colon cancer screening.
The FIT test detects hidden blood in the stool, a potential signal for cancer. In contrast, the DNA test includes quantitative molecular assays for KRAS mutations, aberrant NDRG4 and BMP3 methylation, and β-actin, plus a hemoglobin immunoassay.
The effectiveness of the DNA test was established in a study that evaluated nearly 10,000 asymptomatic patients who were deemed to be at average risk of developing colorectal cancer. It turned out that 65 (0.7%) of these patients had colorectal cancer, and 757 (7.6%) had advanced precancerous lesions. When these patients were screened, the study determined that the sensitivity for detecting colorectal cancer was 92.3% with DNA testing and 73.8% with FIT.