CA15-3 Determination

CA15-3 (MUC1) concentrations were measured by ARCHITECT CA15-3 (Abbott Laboratories, Chicago, IL, USA) on the Architect i2000 System at the Institute of Medical Biochemistry and Laboratory Diagnostics, General University Hospital, and the First Faculty of Medicine of Charles University. While the reason for testing for individual patients is not known, the assay is primarily used at this center for screening for breast cancer patients. The assay is indicated for use with either plasma or serum. Serum was used for the reference population and plasma for the ADTKD-MUC1 and control population. The CA15-3 reference range was 0.0–35 U/mL, with a coefficient of variation of <4.9%. Reference population individuals with CA15-3 levels >35 U/mL were excluded from the analysis, as they likely suffered from metastatic cancer.