Extracolonic findings in an asymptomatic screening population undergoing intravenous contrast-enhanced computed tomography colonography

Background and Aim: The purpose of this study was to evaluate extracolonic findings that could be encountered with computed tomography colonography (CTC) using intravenous (IV) contrast material in an asymptomatic screening population. Methods: Intravenous contrast medium-enhanced CTC was performed in 2230 asymptomatic adults (mean age, 57.5 years). Axial images were prospectively examined for extracolonic lesions. These findings were classified into three categories: potentially important findings, likely unimportant findings, and clinically unimportant findings. Potentially important extracolonic findings were defined as those which required immediate further diagnostic studies and treatment. Clinical and radiologic follow up, missed lesions and clinical outcomes were assessed using medical records (mean duration of follow up, 1.6 years). Results: A total of 115 new potentially important findings in 5.2% of subjects (115/2230) were found. Subsequent medical or surgical intervention was performed in 2.0% (45/2230). New extracolonic cancer was detected in 0.5% (12/2230), and the majority of them (83.3%) were not metastasized. Computed tomography colonography missed eight potentially important extracolonic findings in eight subjects (0.4%, 8/2230): 0.8-cm early-stage prostatic cancer, six adrenal mass and one intraductal papillary mucinous tumor. There were no severe life-threatening complications related to contrast medium. Conclusion: Intravenous contrast-enhanced CTC could safely detect asymptomatic early-stage extracolonic malignant diseases without an unreasonable number of additional work-ups, thus reducing their morbidity or mortality.