Impact of screening colonoscopy on outcomes in colorectal cancer

Colorectal cancer is one of the most common cancers in both men and women worldwide and a good candidate for screening programs. There are two modalities of colorectal cancer screening: (i) population-based screening and (ii) opportunistic screening. The first one is based on organized, well-coordinated, monitored and established programs with a systematic invitation covering the entire target population. In contrast, opportunistic screening tests are offered to people who are being examined for other reasons. Recently, a variety of colorectal cancer screening tests have become available; each country should make a choice, based on national demographics and resources, on the screening method to be used. Fecal occult blood test, especially the fecal immunochemical test, would be the best modality for decreasing colorectal cancer mortality through population-based screening. In contrast, if the aim includes the early detection of colorectal cancer and adenomas, endoscopic methods are more appropriate.