Cholangiocarcinoma CA199 is usually 3 to 5 times higher than 37u/ml. CA199 is a new tumor marker used to diagnose and differentiate pancreatic and bile duct cancers, and is the most sensitive marker known for pancreatic cancer. It is distributed in normal fetal pancreas, liver, intestine and normal adult pancreas and bile duct epithelium. It can be used to assist in the diagnosis of malignant tumors, to monitor changes in the condition of malignant tumors, and can also be used to assess the effectiveness of anti-tumor therapy. The normal value of CA199 is less than 37u/ml, mild elevation may be due to digestive tract inflammation, diabetes, etc., obvious elevation can be seen in digestive tract tumor. In some cholangiocarcinoma patients, this index is 3-5 times of normal value or even higher, but there are also some cholangiocarcinoma patients whose index is within normal range. If the value of ca199 is elevated, it is necessary to go to the hospital for relevant examination to confirm the diagnosis.