[Colorectal cancer screening: comparison among strategies]

Colorectal cancer (CCR) screening is justified since CCR is 2nd leading cause of death for malignancy: most colorectal cancers arise from preexisting adenomatous polyps that remain clinically silent until presentation, often with advanced and incurable malignant disease. The merits and cost-effectiveness of screening for colorectal cancer are evident because the detection and removal of early carcinomas and adenomatous polyps reduces colorectal cancer mortality. Several screening methods are available, each of them presenting advantages and limits. Conventional colonoscopy is considered as the gold standard for the study of colon and, at present, it is the method of screening with the highest effectiveness in reducing CCR morbidity and mortality. However, the use of colonoscopy as the most important screening strategy is limited, because it causes major complications, it has a low compliance, and there are few specialized structures and few specialists to carry out a high number of colonoscopies as screening methods. The screening strategies used at present are described and their advantages and limits are compared.