Meeting the new joint British Society of Gastrointestinal and Abdominal Radiology and Royal College of Radiologists CT colonography standards: a 6-year experience

[Imaging of colorectal cancer: Role of computed tomography colonography]

BACKGROUND

Computed tomography colonography (CTC) is a minimally invasive examination for radiologic imaging of the entire colon and rectum. It has replaced the now obsolete barium enemas and represents an important option to colonoscopy for the detection of colorectal neoplasia.

OBJECTIVES

The aim of this article is to review the current status of CTC for detection of colorectal cancer (CRC) and its precursors.

MATERIALS AND METHODS

Based on an extensive literature research, the current role of CTC in colorectal cancer imaging is summarized. This includes not only CRC detection but also the role of CTC in CRC screening and surveillance.

RESULTS

CTC is a well-developed, minimally invasive examination for the identification of colorectal neoplasia. The diagnostic accuracy for colorectal adenomas and cancer is comparable to that of optical colonoscopy. Missed CRC cases are rare and typically result from perceptual or technical errors. In addition to the detection and characterization of carcinomas, CTC enables the visualization of prestenotic colonic segments and extracolonic structures. This allows for the preoperative detection of synchronous colonic neoplasms that are not endoscopically assessable as well as evaluation of abdominal tumor spread. Due to its ability to detect benign precancerous adenomas with high sensitivity, CTC can be used for opportunistic colorectal cancer screening. In CRC follow-up, CTC may be used to diagnose recurrence if colonoscopy is incomplete or not feasible.

CONCLUSION

CTC is the radiological examination of choice for the detection of colorectal neoplasia. It is typically used in patients where colonoscopy is incomplete, contraindicated or refused. Moreover, CTC serves as a noninvasive option for opportunistic colorectal cancer screening.

Faecal immunochemical testing (FIT) in patients with signs or symptoms of suspected colorectal cancer (CRC): a joint guideline from the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the British Society of Gastroenterology (BSG)

Faecal immunochemical testing (FIT) has a high sensitivity for the detection of colorectal cancer (CRC). In a symptomatic population FIT may identify those patients who require colorectal investigation with the highest priority. FIT offers considerable advantages over the use of symptoms alone, as an objective measure of risk with a vastly superior positive predictive value for CRC, while conversely identifying a truly low risk cohort of patients. The aim of this guideline was to provide a clear strategy for the use of FIT in the diagnostic pathway of people with signs or symptoms of a suspected diagnosis of CRC. The guideline was jointly developed by the Association of Coloproctology of Great Britain and Ireland/British Society of Gastroenterology, specifically by a 21-member multidisciplinary guideline development group (GDG). A systematic review of 13 535 publications was undertaken to develop 23 evidence and expert opinion-based recommendations for the triage of people with symptoms of a suspected CRC diagnosis in primary care. In order to achieve consensus among a broad group of key stakeholders, we completed an extended Delphi of the GDG, and also 61 other individuals across the UK and Ireland, including by members of the public, charities and primary and secondary care. Seventeen research recommendations were also prioritised to inform clinical management.