2022 Volume 71 Issue 2 Pages 270-276
Cancer antigen 72-4 (CA72-4) is a tumor marker that has been used for the monitoring of patients with gastrointestinal cancers such as gastric cancer and mucinous ovarian cancer. In this study, we evaluated the analytical performance of ARCHITECT® CA72-4, which was newly released in January 2021 by Abbott Japan LLC. The analytical performance of this reagent was found to be good with less than 5% CV for both within-run and within-laboratory precisions, and the dilution linearity was confirmed to be also good between 4.3 U/mL and 155 U/mL. The sample was confirmed to be stable for 28 days at 4°C. The correlation between matched serum and plasma samples drawn from the same patients at the same time was n = 102, r = 0.998, y = 0.971x + 0.009, and there was no significant difference observed between the specimen types. The correlation with the control method (Elecsys® CA72-4, Roche Diagnostics K.K.) for patient serum samples was n = 185, r = 0.989, y = 0.948x − 0.769, indicating that the method can be used without any significant difference in performance from the precedent reagent. However, it is necessary to be careful when interpreting the results of measurements when the measurement reagents are different because some unexpected factors are present.
