Extraordinarily elevated serum levels of CA 19-9 and rapid decrease after successful therapy: a case report and review of literature.

Carbohydrate antigen 19-9 is most valuable as a serum marker for pancreatic and biliary cancer, but increased concentrations occur in several other gastrointestinal malignancies. A carbohydrate antigen 19-9 value of >1,000 U/ml usually indicates a digestive cancer and has been reported to have a specificity greater than 99% for pancreatic cancer; nevertheless, false-positive results owing to benign diseases such as pancreatitis or liver cirrhosis have been noted. We present a patient with cholelithiasis and choledocholithiasis with acute cholangitis who had very high serum levels of carbohydrate antigen 19-9 (9586 IU/ml). The rapid decrease in carbohydrate antigen 19-9 after successful treatment was as interesting as the pretreatment high serum level of carbohydrate antigen 19-9.