Abstract
In Western countries, considerable effort has focused on evaluating the ability of CT colonography (CTC) for colorectal cancer screening from the early 2000s. In United States, National CT Colonography Trial (ACRIN6664) suggest CTC is comparable to colonoscopy for the detection of colorectal neoplasia in asymptomatic average-risk adults. Large clinical trials from Germany, Italy, and France also suggest that CTC has high sensitivities and specificities for neoplasia ≥10mm.
The American Cancer Society, the US Multi Society Task Force on Colorectal Cancer, and the American College of Radiology have developed consensus guidelines for the detection of colorectal neoplasia in asymptomatic average-risk adults. In this consensus guidelines, CTC is one of testing options that detect adenomatous polyps and cancer every 5 years. The European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) produced the common guideline regarding indications for CTC in clinical practice. When endoscopy is contraindicated or not possible, ESGE/ESGAR recommend CTC as an acceptable and equally sensitive alternative for patients with symptoms suggestive of colorectal cancer (strong recommendation, high quality evidence).
In Japan, two large clinical trials (UMIN 2097 and 6665) show that CTC has high accuracy in detecting clinically significant neoplasia. Although there are no guidelines or consensus of clinical indications for CTC, it has good indications for health check-up and diagnosis of colorectal neoplasia if colonoscopy is incomplete or contraindicated or not possible. For CTC quality control, evidence-based training and reading and standardization for preparation and examination techniques mandatory.
