The clinical significance of carcinoembryonic antigen (CEA)

        A complex structure of acid glycoprotein, mainly present in adult cancer tissues and fetal gastrointestinal tissues, is a broad-spectrum tumor marker.
 
1. Screening
        Serum CEA is generally not used for tumor screening in asymptomatic people.
 
2. Auxiliary diagnosis
        ① Serum CEA is a relatively broad-spectrum tumor marker. Clinically, it can be used for the auxiliary diagnosis of common tumors such as colon cancer, rectal cancer, lung cancer, breast cancer, esophageal cancer, pancreatic cancer, gastric cancer, metastatic liver cancer and so on. Other malignant tumors such as medullary thyroid carcinoma, cholangiocarcinoma, and urinary system malignancies also have varying degrees of positive rates.
        ② In pregnancy, colitis, colonic polyps, intestinal diverticulitis, pancreatitis, liver cirrhosis, hepatitis, benign lung diseases and cardiovascular diseases, serum CEA may also increase to varying degrees, but the percentage of positive is low.
 
3. Prognosis assessment
        Serum CEA level is one of the factors that determine the prognosis of tumors. Serum CEA continues to rise, indicating a poor prognosis.
 
4. Efficacy and recurrence monitoring
        ① For those who have elevated CEA before treatment, if surgery, chemotherapy, targeted therapy or immunotherapy is effective, the serum CEA concentration drops within the reference range; if the serum CEA only partially or does not decrease after treatment, the treatment effect is not good .
        ② Serum CEA can be used for follow-up and recurrence monitoring after tumor treatment, generally within 2 years after treatment, preferably every 3 months, and every 6 months within 3 to 5 years.