CT colonography (CTC) increased the odds of identifying high-risk lesions in patients undergoing colorectal cancer screening by 78%, primarily by detecting extracolonic lesions, a retrospective cohort study indicates.
“CTC not only identifies colorectal cancer but also doubles the yield of identifying significant early extracolonic lesions, resulting in lives saved,” according to the report in the September issue of the American Journal of Roentgenology.
Ganesh Veerappan, MD, of Walter Reed Army Medical Center, Washington, DC, and associates reviewed the records of 2277 patients who underwent screening CTC between 2003 and 2006. They used a CTC reporting and data system to classify findings as highly significant, likely significant, or insignificant.
Extracolonic lesions were found in 1037 (46%) patients on CTC; the findings were classified as significant in 240 (11%) cases and insignificant in 787. Over a mean follow-up period of 19 months, evaluation of significant findings led to 280 radiology procedures and 19 surgeries.
The total cost of the radiology studies was $113,179, the studies adding approximately $50 per person.
Screening CTC detected 16 high-risk intracolonic and extracolonic lesions compared with nine that would have been detected on optical screening, representing a 78% increase in the yield of high-risk findings. Curative resection was performed on 11 of the 16 lesions, five of which were extracolonic.
Based on these findings, the authors recommend that CTC be considered as either an alternative to optical colonoscopy for colorectal cancer screening or as a one-time procedure to identify significant treatable intracolonic and extracolonic lesions.