CA199 value rises to 300 U/mL, need to be alert to the presence of pancreatic or gastrointestinal malignant tumors, it is recommended to carry out pancreatic CT and gastroenteroscopy. Under normal circumstances, CA199 is a kind of glycan antigen, its normal value is 0~37U/mL, the diagnostic sensitivity for pancreatic malignant tumor can reach more than 70%; for other digestive tract malignant tumors such as gastric cancer, colon cancer, liver malignant tumors also have a certain diagnostic rate. Excluding malignant tumors, other inflammatory diseases or benign tumors, such as cirrhosis, pancreatitis, cholecystitis, etc., can also show elevated values, but the magnitude of the increase is relatively small. If CA199 value is found to be significantly elevated, it is recommended to consult a regular hospital for further examination under the guidance of a physician to find out the cause and make a clear diagnosis, so as to avoid delaying the condition.