title: The value of serum CA 19-9 in predicting cholangiocarcinomas in patients with primary sclerosing cholangitis.
abstract: CA 19-9 has been used with questionable accuracy to aid diagnosis of cholangiocarcinoma complicating primary sclerosing cholangitis. We aimed to characterize the test properties of CA 19-9 and of a change in CA 19-9 over time in predicting cholangiocarcinoma. Charts of 208 patients were reviewed. Fourteen patients had cholangiocarcinoma. Median CA 19-9 was higher with cholangiocarcinoma (15 vs. 290 U/ml, p < 0.0001). A cutoff of 129 U/ml provided: sensitivity 78.6%, specificity 98.5%, adjusted positive predictive value 56.6% and negative predictive value 99.4%. The median change over time was 664 U/ml in cholangiocarcinoma compared to 6.7 U/ml in primary sclerosing cholangitis alone (p < 0.0001). A cutoff of 63.2 U/ml for change in CA 19-9 provided: sensitivity 90%, specificity 98% and positive predictive value 42%. Only 2 patients with cholangiocarcinoma were the candidates for curative therapy. In conclusion, the positive predictive value of an elevated CA 19-9 was 56.6%; only advanced cases were detected by this method.
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Florida, Gainesville, USA.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Levy
authors.forename: James
authors.initials: J
authors.lastname: Lymp
authors.forename: Paul
authors.initials: P
authors.lastname: Angulo
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Gores
authors.forename: Nicholas
authors.initials: N
authors.lastname: Larusso
authors.forename: Keith D
authors.initials: KD
authors.lastname: Lindor
mesh_terms: D001650:Bile Duct Neoplasms / Q000097:blood / Q000209:etiology*; D018395:CA-19-9 Antigen / Q000097:blood*; D018281:Cholangiocarcinoma / Q000097:blood / Q000209:etiology*; D015209:Cholangitis, Sclerosing / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012016:Reference Values
chemical_list: D018395:CA-19-9 Antigen