CA19-9 serum levels in obstructive jaundice: clinical value in benign and malignant conditions.
BACKGROUND
Obstructive jaundice is frequently associated with false CA19-9 elevation in benign conditions. The diagnostic accuracy of this tumor marker was evaluated in the present longitudinal study.


METHODS
In 128 patients admitted for obstructive jaundice (87 with pancreato-biliary malignancy and 41 benign disease) serum CA19-9 was measured. Statistical analysis of marker levels obtained before and after endoscopic biliary drainage was performed in 60 patients.


RESULTS
Elevated CA19-9 levels (>37 U/mL) were found in 61% of benign cases and 86% of malignancies. After biliary drainage, decrease of serum CA19-9 was observed in 19 of 38 malignant cases and in almost all benign cases (Wilcoxon matched pairs test: P = .207 and P <.001, respectively). Receiver operating characteristic (ROC) analysis identified a cut-off value of 90 U/mL to be associated with improved diagnostic accuracy after biliary drainage (sensitivity 61%, specificity 95%).


CONCLUSIONS
In the presence of successfully drained obstructive jaundice, CA19-9 serum levels that remain unchanged or measure more than 90 U/mL are strongly indicative of a malignant cause of obstruction. However, the real clinical utility of this marker remains controversial.
Marrelli
Daniele
D
Department of Human Pathology and Oncology, Unit of Surgical Oncology, University of Siena, Viale Bracci-Policlinico Le Scotte, Siena, Italy. marrelli@unisi.it
Caruso
Stefano
S
Pedrazzani
Corrado
C
Neri
Alessandro
A
Fernandes
Eduardo
E
Marini
Mario
M
Pinto
Enrico
E
Roviello
Franco
F
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001661:Biliary Tract Neoplasms / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D014408:Biomarkers, Tumor / Q000097:blood; D018395:CA-19-9 Antigen / Q000097:blood*; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003937:Diagnosis, Differential; D004322:Drainage; D005260:Female; D006801:Humans; D041781:Jaundice, Obstructive / Q000097:blood* / Q000175:diagnosis / Q000209:etiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D011237:Predictive Value of Tests; D012372:ROC Curve; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen