CT Colonography Accurate for 10 mm Adenomas
Less accurate for smaller lesions; better patient scores for comfort, exam preparation
MONDAY, May 14 (HealthDay News) -- For patients at average-to-moderate risk of colon cancer, computed tomographic colonography (CTC) accurately detects adenomas 10 mm or larger, but not smaller lesions, according to a study published in the May 15 issue of the Annals of Internal Medicine.
Michael E. Zalis, M.D., from Massachusetts General Hospital in Boston, and colleagues conducted a prospective test comparison of laxative-free CTC, which involves electronic cleansing and computer-aided detection, and optical colonoscopy (OC) for detection of adenomas in 605 adults aged 50 to 85 years.
The researchers found that, for adenomas 10 mm or larger, the per-patient sensitivity and specificity of CTC was 0.91 and 0.85, respectively. The corresponding values for OC were 0.95 and 0.89. For adenomas at the threshold of 8 mm or larger, the corresponding values were 0.70 and 0.86 for CTC and 0.88 and 0.91 for OC. For adenomas 6 mm and larger, the sensitivity and specificity were 0.59 and 0.88, respectively, for CTC, and 0.76 and 0.94, respectively, for OC. Patients reported greater comfort and less difficulty of examination preparation for CTC than for OC.
"Computed tomographic colonography was accurate in detecting adenomas 10 mm or larger but less so for smaller lesions," the authors write. "Patient experience was better with laxative-free CTC. These results suggest a possible role for laxative-free CTC as an alternate screening method."
The study was supported by grants from GE Healthcare. Several authors are co-inventors of electronic cleansing and computer-aided detection software patents.