Current and evolving strategies for colorectal cancer screening.

BACKGROUND: Colorectal cancer is a major cause of cancer mortality and morbidity. Screening can potentially prevent most colorectal cancers by detection and removal of precursor adenomas.
METHODS: The literature and clinical practice guidelines are reviewed, with an emphasis on advances of the last 10 years and evolving screening methods.
RESULTS: Colonoscopy has come to be used for screening in persons at average risk for colorectal cancer because of the comparative ineffectiveness of other methods, although these methods continue to be recommended. Virtual colonoscopy and fecal DNA testing are emerging technologies with promise to be more effective than fecal occult blood testing or sigmoidoscopy in selecting those persons who should undergo colonoscopy. Next to age, family history is the most common risk factor for colorectal cancer and one that warrants more aggressive screening and, in some instances, genetic counseling and testing. Hereditary nonpolyposis colorectal cancer accounts for as many as 1 in 20 colorectal cancers, but to take advantage of recent advances in genetic testing for this disorder, a high level of clinical suspicion must be maintained.
CONCLUSIONS: If we are to reduce mortality and morbidity from colorectal cancer, practicing clinicians need to be aware of current and evolving strategies for colorectal screening, and assertively recommend the appropriate strategy to their patients.