Fecal DNA testing = Hemoccult Sensa for colon cancer screening

Clinical Question

Is fecal DNA testing superior to high-sensitivity fecal occult blood testing for detecting colorectal cancer in average-risk adults?

Bottom Line

Fecal DNA screening did not provide an advantage over high-sensitivity fecal occult blood testing (FOBT) in a general population at average risk for colorectal cancer. A new version of the DNA test may detect more cancers but also may produce more false positive results as compared with a high-sensitivity FOBT, such as Hemoccult Sensa. (LOE = 2b)


Ahlquist DA, Sargent DJ, Loprinzi CL, et al. Stool DNA and occult blood testing for screen detection of colorectal neoplasia. Ann Intern Med 2008;149(7):441-450.  [PMID:18838724]

Study Design

Cohort (prospective)




Outpatient (specialty)


Fecal DNA testing as screening tool for colorectal cancer has been endorsed by several groups, including the American Cancer Society. However, the United States Preventive Services Task Force's latest statement does not give a recommendation, citing insufficient evidence to compare benefits and harms. The US researchers conducting this study recruited 3764 average-risk adults in 22 communities across the United States. The patients were aged 50 years to 80 years, without symptoms, who had not had either a colonoscopy in at least 10 years or FOBT screening in the past year. All patients received 4 screens: FOBT using Hemoccult, FOBT using Hemoccult Sensa, colonoscopy, and a fecal DNA test. The fecal DNA test is not yet commercially available and was changed to another version from the same company following the enrollment of 2497 patients. All tests were performed by personnel unaware of the results of the other tests. Using colonoscopy as the gold standard, the sensitivity of the first fecal DNA test and Hemoccult Sensa were similar (20%-21%). Specificity was similar among the 3 methods. In a second aspect of the study using a new version of the DNA test in a selected group (ie, not a screening), the new version of the DNA test detected more relevant neoplasms than FOBT, though significantly more patients were labeled falsely as positive than with FOBT (16% vs 4%-5%).