A 3-year prospective study on serum tumor markers used for detecting cholangiocarcinoma in patients with primary sclerosing cholangitis

Background/Aims: Patients with primary slerosing cholangitis (PSC) have an increased risk of developing cholangiocarcinoma (CC), which is notoriously difficult to diagnose since these patients may have increased levels of bil irubin due to benign strictures. To evaluate the validity of different tumo r markers as an aid to diagnosing CC, we have carried out serial serum tumo r marker analyses in patients with PSC who have been followed for several y ears. Methods: Seventy-five patients with PSC, without any clinical signs of CC w ere included in the study. They were investigated every 6th months for 3 ye ars, with extensive liver function tests and four tumor serum markers CEA, CA 19-9, CA 50 and CA 242. The patients were then followed for 5 years to e xclude the possibility that CC remained unrecognized. Results: Of the 75 patients, two (3%) developed CC during the 3-year period . One of these had normal levels, and one had significantly increased level s of the tumor markers. In the follow-up part of the study two further pati ents died from CC and one from hepatocellular carcinoma, 3 and 4 years afte r the 3-year study, respectively. Twenty-one patients had an increase of on e of the markers on at least one occasion. Five patients had a transient in crease of more than double the upper normal limit of the tumor markers on m ore than one occasion. There was a good correlation between CA 19-9, CA 50 and CA 242, but not with CEA. Fourteen of the 75 patients had periods of in creased bilirubin levels, but none of these showed increased tumor markers. Conclusions: The serum tumor markers CEA, CA 19-9, CA 50 and CA 242 are of limited value for the detection of CC in patients with PSC because of low s pecificity. However, we found no falsely increased values in patients with hyperbilirubinemia.