How to Interpret CTC Data: Evaluation of the Different Lesion Morphologies

A climatic new era of data validation has been reached for CTC screening in both asymptomatic cohorts and patients at increased risk (Johnson et al. 2008; Graser et al. 2009; Regge 2009; Kim et al. 2007; Pickhardt et al. 2003). In 2008 the American Cancer Society released a joint guideline with the US Multisociety colorectal task force and the American College of Radiology recommending CTC, along with other proven modalities, for colorectal screening (Levin et al. 2008). Thus, the pathway to broader community implementation of CTC for screening has began to evolve in the United States and worldwide (Thomas et al. 2008). Concordant with the continued technological evolution and increased translation into screening cohorts, there is a need to reinforce how to most effectively interpret the data.

Important differences in acquisition methods have varied in stool tagging and low-dose techniques, while image display techniques have ranged from primary detection with 2D multiplanar reformation (2D MPR) to 3D endoscopic fly-through techniques. Although differences exist, there are key issues of image display techniques which are important to understand for data interpretation.