Extracolonic findings at CT colonography

Computed tomographic colonography (CTC) is a validated tool for the evaluation of the colon for polyps and cancer. The technique employed for CTC includes a low-dose CT scan of the abdomen and pelvis that is typically performed without the administration of intravenous contrast. Using this technique it is possible to discover findings outside of the colon. By far, most extracolonic findings are determined to be clinically inconsequential on CTC and most patients are not recommended for further testing. However, some findings may result in additional diagnostic evaluation or intervention, which can lead to patient anxiety and increased morbidity and health care costs. Alternatively, some findings can lead to the earlier diagnosis of a clinically significant lesion, which could result in decreased patient morbidity and mortality as well as overall savings in downstream health care costs. The controversies of detecting and evaluating these incidental extracolonic findings on CTC are discussed.