Cancer antigen 19-9 (CA 19-9) is associated with gastrointestinal cancer. Elevated level of CA 19-9 has been reported in various other complications such as a colorectal cancer, esophageal cancer and hepatocellular carcinoma. CA 19-9 is the most widely studied and validated serum biomarker for the diagnosis of pancreatic cancer. CA 19-9 serum levels can provide important information with regards to prognosis and overall survival.; Form/Appearance: Liquid; 50 mM PBS (pH 7.2-7.6) and 0.15 % w/v Sodium Azide, 1 KU