Factors affecting serum levels of CA 19-9 with special reference to benign hepatobiliary and pancreatic diseases.

In order to elucidate the factors affecting the serum levels of CA 19-9, we analyzed sera of 79 patients with pancreatic cancer and 169 with non-malignant diseases, chiefly consisting of hepatobiliary and pancreatic diseases. Serum CA 19-9 values in patients with pancreatic cancer had no relation to the location of the tumor or presence of jaundice. Similarly, no tendency was observed as to the location and size of tumor or to the grade of differentiation in 12 CA 19-9-negative patients with pancreatic cancer. Serum levels of CA 19-9 in patients with cholelithiasis complicated by cholangitis frequently showed markedly high values, but then rapidly normalized in parallel with the subsiding of inflammation. The behaviour of serum CA 19-9 showed little relation to renal or hepatic failures or to intrahepatic cholestasis. However, slightly elevated levels of the antigen were found in more than half of those patients with fulminant hepatitis showing massive necrosis. In chronic pancreatitis, the prevalence was only 8%; however, an increase was observed at the time of exacerbation in 2 of 5 positive patients. There was hardly any increase in serum levels of CA 19-9 after endoscopic retrograde cholangiopancreatography (ERCP), although serum levels of pancreatic enzymes rose after ERCP in almost all patients. Thus, it appears that CA 19-9 does not easily escape into the bloodstream, unlike pancreatic enzymes.