Is jaundice a cause of error in the interpretation of CA 19-9 blood levels?
Nakad, A.; Colombel, J.F.; Geubel, A.P.; Cerulus, G.; Farchakh, E.; Degrez, T.; Janssen, J.; Cortot, A.; Paris, J.C.; Dive, C.
Acta Gastro-Enterologica Belgica 52(1-2): 17-22
1989
ISSN/ISBN: 1784-3227 PMID: 2618531 Document Number: 339625
Serum CA 19-9 has been proposed as a tumour marker for pancreatic cancer (PC). However, false positive results are seen in sera of patients with benign jaundice. The CA 19-9 assay was performed by a solid state radioimmunoassay in 86 icteric patients (total bilirubin greater than 2 mg/dl). 24/86 had PC (12 men, 12 women, mean age 74 years) and 62/86 had benign jaundice (29 men, 33 women, mean age 56 years; cirrhosis: n = 20, angiocholitis: n = 21, hepatitis: n = 21). At a cut-off level of 60 U./ml, for detecting icteric PC, sensitivity was 83%, and specificity was 79%. At 120 U./ml, sensitivity was 79%, but specificity was increased to 92%. We conclude that 21% of patients with benign jaundice had a CA 19-9 level greater than 60 U./ml, and using a CA 19-9 level of 120 U./ml, the specificity of the test to detect icteric PC was increased, with little decrease in the sensitivity.