Enhanced discrimination of malignant from benign pancreatic disease by measuring the CA 19-9 antigen on specific protein carriers.
The CA 19-9 assay detects a carbohydrate antigen on multiple protein carriers, some of which may be preferential carriers of the antigen in cancer. We tested the hypothesis that the measurement of the CA 19-9 antigen on individual proteins could improve performance over the standard CA 19-9 assay. We used antibody arrays to measure the levels of the CA 19-9 antigen on multiple proteins in serum or plasma samples from patients with pancreatic adenocarcinoma or pancreatitis. Sample sets from three different institutions were examined, comprising 531 individual samples. The measurement of the CA 19-9 antigen on any individual protein did not improve upon the performance of the standard CA 19-9 assay (82% sensitivity at 75% specificity for early-stage cancer), owing to diversity among patients in their CA 19-9 protein carriers. However, a subset of cancer patients with no elevation in the standard CA 19-9 assay showed elevations of the CA 19-9 antigen specifically on the proteins MUC5AC or MUC16 in all sample sets. By combining measurements of the standard CA 19-9 assay with detection of CA 19-9 on MUC5AC and MUC16, the sensitivity of cancer detection was improved relative to CA 19-9 alone in each sample set, achieving 67-80% sensitivity at 98% specificity. This finding demonstrates the value of measuring glycans on specific proteins for improving biomarker performance. Diagnostic tests with improved sensitivity for detecting pancreatic cancer could have important applications for improving the treatment and management of patients suffering from this disease.
Laboratory of Cancer Immunodiagnostics, Van Andel Institute, Grand Rapids, Michigan, United States of America.
Tingting
T
Yue
Kevin A
KA
Maupin
Brian
B
Fallon
Lin
L
Li
Katie
K
Partyka
Michelle A
MA
Anderson
Dean E
DE
Brenner
Karen
K
Kaul
Herbert
H
Zeh
A James
AJ
Moser
Diane M
DM
Simeone
Ziding
Z
Feng
Randall E
RE
Brand
Brian B
BB
Haab
D014408:Biomarkers, Tumor / Q000097:blood; D018394:CA-125 Antigen / Q000097:blood; D018395:CA-19-9 Antigen / Q000097:blood*; D002352:Carrier Proteins / Q000097:blood*; D003937:Diagnosis, Differential; D006801:Humans; D008565:Membrane Proteins / Q000097:blood; D055271:Mucin 5AC / Q000097:blood; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000175:diagnosis*; D040081:Protein Array Analysis
D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D018395:CA-19-9 Antigen; D002352:Carrier Proteins; C451759:MUC16 protein, human; C524678:MUC5AC protein, human; D008565:Membrane Proteins; D055271:Mucin 5AC