C. Daniel Johnson, M.D., of the Mayo Clinic in Scottsdale, Ariz., and colleagues conducted a post-hoc analysis of National CT Colonography Trial data involving 2,600 asymptomatic subjects, 497 of whom were 65 years of age or older, to compare the specificity and sensitivity of CT colonography for older and younger participants. The primary end point was the ability to detect histologically confirmed colorectal neoplasia that were 10 mm or larger in diameter.
The researchers found that adenomas 1 cm or larger were present in 6.9 percent of the 477 older patients who had complete data available, compared with 3.7 percent of participants aged 50 to 65 years. There were no statistically significant differences in the accuracy of CT colonography for the detection of large and intermediate-sized colorectal neoplasia between older and younger patients. For large neoplasms, the sensitivity and specificity were 0.82 and 0.83, respectively, for older patients and 0.92 and 0.86, respectively, for younger patients.
“In summary, a post-hoc analysis of data from the National CT Colonography Trial did not find significant differences in the diagnostic accuracy of CT colonography for the detection of large and intermediate-size adenomatous lesions in participants 65 years of age and older compared with younger participants,” the authors write.