Screening for colorectal cancer in asymptomatic average risk patients : role of imaging

Early detection of colorectal cancer or advanced adenomas is a public health priority in many industrialized countries. There are various methods of screening average risk individuals for colorec- tal cancer, and their effectiveness may depend on subjective parameters like local expertise and patient's preferences. This paper reviews these tests with special emphasis regarding imaging techniques that aim to provide less-invasive alternatives to optical colonoscopy (OC) which is the standard of reference. Both Double- Contrast Barium Enema (DCBE) and Virtual Colonoscopy (VC) have >90% sensitivity compared to OC in the detection of clinical- ly relevant colonic lesions. Nevertheless, VC may have an edge over DCBE for technical and reproductivity reasons, as well as greater learning opportunities. Imaging techniques criticisms regarding diminutive and flat lesions, cost, radiation exposure and effects on gastroenterological practice are addressed. (Acta gastroenterol. belg., 2011, 74, 70-76).