Colorectal cancer screening: practice guidelines.

Colorectal cancer (CRC) screening has been demonstrated to reduce both incidence and mortality of CRC. There are several different screening options, each with potential benefits and some limitations. Fecal blood tests are primarily early cancer detection tests, which have been shown to reduce CRC mortality. Structural exams of the colon (flexible sigmoidoscopy, colonoscopy and imaging) may identify cancer precursor lesions (adenomas) and early cancer. There is evidence that detection and removal of adenomas may prevent many cancers. New forms of screening using stool DNA, capsule endoscopy and serum testing for genetic mutations are still in evolution, though proof-of-principle studies have been published.