CT colonography: accuracy, acceptance, safety and position in organised population screening

Abstract

Colorectal cancer (CRC) is the second most common cancer and second most common cause of cancer-related deaths in Europe. The introduction of CRC screening programmes using stool tests and flexible sigmoidoscopy, have been shown to reduce CRC-related mortality substantially. In several European countries, population-based CRC screening programmes are ongoing or being rolled out. Stool tests like faecal occult blood testing are non-invasive and simple to perform, but are primarily designed to detect early invasive cancer. More invasive tests like colonoscopy and CT colonography (CTC) aim at accurately detecting both CRC and cancer precursors, thus providing for cancer prevention. This review focuses on the accuracy, acceptance and safety of CTC as a CRC screening technique and on the current position of CTC in organised population screening. Based on the detection characteristics and acceptability of CTC screening, it might be a viable screening test. The potential disadvantage of radiation exposure is probably overemphasised, especially with newer technology. At this time-point, it is not entirely clear whether the detection of extracolonic findings at CTC is of net benefit and is cost effective, but with responsible handling, this may be the case. Future efforts will seek to further improve the technique, refine appropriate diagnostic algorithms and study cost-effectiveness.

The conundrum of the young colon cancer patient

“…27 Another rapid and noninvasive possibility would be to use CT colonography as a screening method, but this raises the issue of radiation exposure, which potentially has more consequences in younger patients. 28 With the predominance of distal tumors witnessed in younger patients, and considering the higher rates of metastasis and mortality in sigmoid tumors previously demonstrated, 29 there may be a role for recommending sigmoidoscopy in this age group which would clearly be significantly less costly than recommending a full colonoscopy.…”

Colorectal Cancer Screening

“…54 Issues such as cost-effectiveness and the consequences of extracolonic findings need to be clarified before CTC can be widely implemented in population-based screening. 55 …”

Irritable bowel syndrome evaluation using computed tomography colonography

“…Computed tomographic colonography (CTC), similar to colonoscopy but less invasive, is an examination procedure developed for detecting colonic adenomatous lesions[12-14]. Both colonoscopy and CTC examine the full length of the colon, and their use in screening would be expected to result in colorectal cancer (CRC)-related mortality rates lower than those obtained using sigmoidoscopy or stool-based tests.…”