Carcinoembryonic antigen as a marker for colorectal cancer: is it clinically useful? Clin

the most widely used tumor markers worldwide. Its main application is mostly in gastrointestinal cancers, especially in colorectal malignancy. Although in use for almost 30 years, the clinical value of CEA in colorectal cancer is still not clear. Methods: The literature relevant to the clinical value of CEA in colorectal cancer was reviewed. Particular atten-tion was paid to studies involving metaanalyses and guidelines issued by Expert Panels. Results: Although of little use in detecting early colo-rectal cancer, high preoperative concentrations of CEA correlate with adverse prognosis. Serial CEA measure-ments can detect recurrent colorectal cancer with a sensitivity of;80%, a specificity of;70%, and can provide a lead time of;5 months. CEA is the mos