Are serum and biliary carcinoembryonic antigen and carbohydrate antigen19-9 determinations reliable for differentiation between benign and malignant biliary disease?

BACKGROUND/AIMS: The value of serum tumor markers carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) in the differential diagnosis of obstructive biliary disease is dubious. We aimed to define their usefulness prospectively. METHODS: Thirty-seven consecutive patients (12 female, 25 male, median age: 54, range: 19-83 years) who were referred for endoscopic retrograde cholanugiopancreatography (ERCP) or percutaneous transhepatic cholangiography (PTC) examination for obstructive jaundice were included (all with dilatation of biliary tree in ultrasonography or computerised tomography). Bile was obtained through the nasobiliary or external drainage catheter, placed with ERCP or PTC, respectively. Serum samples were taken from all patients at the time of acquisition of bile. Serum and bile samples were stored at -50 oC until they were tested. CA19-9 and CEA levels were measured with chemiluminescent enzyme immunoassay methods in serum and bile samples by using immulite GI-MA and CEA commercial kits, respectively (DPC(r), Los Angeles). RESULTS: In 22 patients with malignant disease, serum CEA levels were 38.6+/-115.8 ng/ml and CA19-9 were 386.9+/-409.7 U/ml, while in 15 patients with benign disease the serum CEA levels were 1.8+/-1.6 ng/ml and CA19-9 were 128.9+/-302.2 U/ml. The difference for both values was significant (p 0.05). CONCLUSION: It was concluded that serum CA19-9 levels are increased both in malignant and benign obstructive biliary diseases, albeit more significantly in the former. However, increase in serum CEA is mostly restricted to malignant diseases. Measurement of these markers in bile is of no value.