Does This Patient Have Pancreatic-Biliary Cancer?

Abstract

Purpose: Introduction: CA 19-9 (serum carbohydrate antigen 19-9) is a glycosphingolipid that was first isolated in 1979 by Koprowski as a monoclonal antibody to cultured cell from human colonic cancer. Since then, it has been used as a tumor marker for pancreatic and biliary cancers. However, high levels of CA 19-9 are occasionally found in benign diseases of the liver and biliary tract with a value usually <5000 U/m. Case: This is a 69-year-old morbidly obese male patient who presented with a 2 day history of painless jaundice with no history of viral hepatitis or liver disease and his family history was significant for pancreatic carcinoma. Physical examination revealed an obese male with scleral icterus and jaundice. Laboratory studies showed aspartate aminotransferase: 196 U/L; alanine aminotransferase: 15 U/L; alkaline phosphatase: 1045 U/L; total bilirubin: 12 mg/dL; carcinoembryonic antigen: 3.2 ng/mL; CA 19-9: 38,310 U/mL. Ultrasonography and computerized tomography of the abdomen were of poor quality due to body habits. Magnetic resonance imaging of the abdomen showed intrahepatic biliary dilatation, a dilated common bile duct of 11 mm and no pancreatic mass. Endoscopic ultrasound was then performed and showed stones in gall bladder as well as an impacted stone in the ampula and normal pancreatic head. Endoscopic retrograde cholangiopancreaticography was then attempted but with failure to cannulate the bile due to body habitus. After 2 days, his symptoms started to improve. A repeat CA 19-9 level obtained 1 week later was 36 U/mL. Discussion: CA 19-9 is produced in normal pancreatic and biliary ductal cells with upper limit of normal 37-40 U/mL, and significant elevations above 1,000 U/mL being 99% specific for the diagnosis of pancreatic cancer. Extreme elevations of serum CA 19-9 levels with benign biliary tract diseases have been reported in the literature. Several hypothesis have been postulated to explain the degree of elevation: 1) Inflammation resulting in increased proliferation of the epithelial cells leading to increased production of CA 19-9; 2) Biliary tract obstruction leading to accumulation of CA 19-9 in the biliary lumen; 3) Increased biliary pressure leading to irritation of bile duct cells and increased production of CA 19-9; 4) Reflux of CA 19-9 into the circulation by obstruction. Tumor markers alone should never use to establish the diagnosis of malignancy.Figure: EUS: Stone in ampulla.