MUC1 serum assays in breast cancer: tumor specificities and reference levels.

The aim of the study was to establish reference ranges and to explore the tumor specificities of two automated assays for MUC1. Sera from 124 female blood donors, 144 patients with benign disease of the breast, 69 patients with stage I, 75 with stage II, 89 with stage III and 38 patients with stage IV breast cancer were analyzed for MUC1 levels using two automated immunometric assays employing assay antibody pairs Ma695/Ma552 and BC2/GP1.4, respectively.

Immunometric assay interference: incidence and prevention.

Background: The primary aim of the study was to reduce interference in an in-house two-site, two-step immunometric assay.

Methods: In the running laboratory routine, 11 261 samples were tested with a carcinoembryonic antigen (CEA) assay with bovine immunoglobulin but no murine immunoglobulins in the buffer, in parallel to our routine CEA assay, using 15 mg/L heat-treated nonspecific murine immunoglobulin (MAK33) in the buffer and with the Fc fragments removed from the capture antibody.

Results: The frequency of interference was estimated to be 4.