Introduction: Carbohydrate antigen 19-9 (CA 19-9) is the most valuable as a serum tumor marker for pancreatic and biliary cancers. Different assays may show significant differences in individual patients or some samples. The aim of this paper is to explore the causes of differences in results from different instruments and to avoid them.
Methods: CA19-9 was detected using ARCHITECT i2000 analyzer. If the results of CA 19-9 on the ARCHITECT i2000 analyzer were over 39 U/mL, the serum specimens were secondly tested using Roche cobas e601 analyzer. The differences of CA19-9 were analyzed in samples between different instruments.
Results: The CA 19-9 concentrations tested using ARCHITECT i2000 assayer were significantly higher than that in cobas e601 assayer of all specimens, males and females (p=0.000, all). Of the 158 specimens, 106 specimens were inconsistent, and 52 specimens were consistent.
Conclusion: Gender and nonmalignant diseases were not the reasons induced the discordant results. If there is any clinical doubt about a result, CA 19-9 should be determined using another method to exclude possible interferences.
Published Date: 2022-03-14; Received Date: 2022-02-14