Glycoantigen assay chemiluminescence is mainly used for tumor screening, checking the effectiveness of tumor treatment as well as recurrence and metastasis. There are many types of glycan antigen tests, including cancer antigen 72-4, cancer antigen 12-5, glycan antigen 19-9, cancer antigen 15-3, and cancer antigen 50. It can be used for tumor screening and also for monitoring the effect of tumor treatment and recurrence and metastasis. For example, patients with cholangiocarcinoma, gallbladder cancer and pancreatic cancer will show a very obvious increase in Glycoantigen 19-9, and patients with breast cancer will show an increase in Glycoantigen 15-3, etc. When the treatment is effective, the Glycoantigen can be used to detect the recurrence and metastasis of the tumor. Glycoantigens may decrease significantly when treatment is effective, and then increase again in the event of recurrence and metastasis. However, some benign diseases can also lead to an increase in GAA, so a combination of imaging and pathology is needed to make a comprehensive judgment. Therefore, the measurement of glycoantigens is only used as an aid to diagnosis, and it is recommended that patients with elevated glycoantigens should seek prompt medical attention to identify the cause of the elevation, and then actively treat the disease.