CARCINOEMBRYONIC ANTIGEN- CEA
Pre-test preparation or requirements
• Sample can be drawn at any time. No fasting or special preparation required.
• Sample should taken in plain vial.
Significance of test
CEA is mainly found the fetal gastro-intestinal tract and in fetal serum. It also occurs in slight quantities in intestinal, pancreatic and hepatic tissue of healthy adults. The formation of CEA is repressed after birth and accordingly serum CEA values are hardly measureable in healthy adults. High CEA concentrations are frequently found in cases of colorectal adenocarcinoma. The result of clinical studies indicates that CEA, although originally thought to be specific for digestive tract cancers, may also be elevated in other malignancies and in some nonmalignant disorders. Slight to moderate CEA elevations occur in benign diseases of the intestine, pancreas, liver and lungs. Thus CEA is not specific marker of malignancies. However the detection of blood CEA indicates the growth of the tumor. After resection of the tumor, the CEA level should be lower until to normal. A persistently rising CEA values may be associated with progressive malignant disease and a poor therapeutic response. This situation indicates local recurrence or distant metastasis of cancer cells. Studies have shown that elevated CEA levels predict recurrence of colorectal cancer and liver metastasis, earlier than imaging and clinical examination.