Elevated tumor markers most often indicate a malignant tumor, but can also be due to non-tumor conditions such as pregnancy, inflammation, and benign liver disease. Generally speaking, elevated tumor markers may represent malignant tumors or their recurrence, for example, carcinoembryonic antigen can be elevated in colon, lung and breast cancers; monitoring carcinoembryonic antigen after colorectal cancer surgery can predict recurrence; alpha-fetoprotein can also be elevated in patients with hepatocellular carcinoma, which needs to be combined with the patient’s clinical symptoms to perform the relevant examination. However, normal cells also secrete tumor markers, and their elevation may indicate other non-tumor diseases. Pregnant women, inflammation, bronchial asthma, emphysema, alcoholic cirrhosis, active hepatitis, etc. can cause high tumor markers. Elevated tumor markers should be reviewed, and if they are elevated several times in a row, relevant tests should be performed as prescribed by the doctor to avoid delaying treatment.