CA 19-9

CA 19-9 is a tumor marker. Tumor markers are substances that are produced by cancer or by other cells of the body in response to cancer or certain benign (noncancerous) conditions. Most tumor markers are made by normal cells as well as by cancer cells; however, they are produced at much higher levels in cancerous conditions.


CA 19-9 is the most extensively studied and validated serum biomarker for the diagnosis of pancreatic cancer in symptomatic patients. CA 19-9 serum levels can provide important information with regards to prognosis, overall survival, and response to chemotherapy as well as predict post-operative recurrence. However, there's non-specific expression of CA 19-9 in several benign and malignant diseases


CA19-9 is usually measured by a blood test.


CA 19-9 serum levels may also be elevated in in several benign and malignant diseases, pancreatic and non-pancreatic


Other conditions associated with elevated serum CA 19-9 levels include:

• ovarian cyst
• heart failure
• Hashimoto's thyroiditis
• rheumatoid arthritis
• diverticulitis
• choledocholithiasis, gallbladder cancer and cholangiocarcinoma. 
• CA 19-9 serum levels alone cannot differentiate between benign, precursor lesions and malignant pancreatic conditions such as acute and chronic pancreatitis, intraductal pancreatic mucinous neoplasms (IPMN), pancreatic intra-epithelial neoplasia (PANIN) and pancreatic cancer.

Sources: National Cancer Institute /  U K Ballehaninna; R S Chamberlain Journal of Gastrointestinal Oncology