S1650 Severely Elevated CA19-9: Benign or Malignant?

Abstract

Introduction: CA 19-9 is a carbohydrate antigen and a widely used biomarker for pancreatic cancer, however it can be elevated in extra-pancreatic malignancies and benign conditions. Generally, CA 19-9 levels are significantly lower in benign than in malignant conditions, and levels resolve once the primary obstruction or inflammatory offense is treated. We present a case of a male who was found to have critically elevated CA 19-9 without evidence of pancreatic malignancy. Case Description/Methods: A healthy 51-year-old male presented to the emergency room with generalized itchiness and painless jaundice for two weeks. Symptoms originally began with abdominal pain that quickly resolved, but was followed by jaundiced skin, dark urine, and clay colored stools. His physical exam was positive for scleral icterus and jaundice, with a negative abdominal exam. His laboratory values in the emergency room were significant for an elevated total bilirubin of 15.8 mg/dl, direct bilirubin of 11.8 mg/dl, elevated alkaline phosphatase 521 U/L, elevated AST of 56 U/L and ALT of 103 U/L without leukocytosis. The MRCP revealed choledocholithiasis and the patient was planned for an endoscopic retrograde cholangiopancreatography (ERCP) for further evaluation of the obstructive jaundice. While pending ERCP, a critically elevated CA 19-9 came back at 23,398.5 U/ML. He subsequently had an ERCP that confirmed the presence of the choledocholithiasis, and he underwent a biliary sphincterotomy with biliary stent placement. No masses were appreciated during either MRCP or ERCP. Pathology from duodenal ampulla was negative for dysplasia. The patient was discharged home the next day with outpatient follow-up. Discussion: CA 19-9 is not specific for pancreatic carcinoma, as it has been found elevated in extra-pancreatic malignancies and benign conditions such as disease of the hepatobiliary system, pneumonia, pleural effusion, renal failure and SLE. In a retrospective review of all patients who had CA 19-9 levels measured, markedly raised levels of more than 10,000 U/ml were observed in patients with advanced stages of colorectal, pancreatic and lung carcinoma. In benign conditions, no patients had a CA 19-9 level greater than 500 and only 2 cases of cirrhosis and cholecystitis had a level between 200-500. Although our patient did not have any evidence of malignancy, it should be kept on the differential if his outpatient work-up reveals persistently elevated CA 19-9 levels despite resolution of biliary obstruction.