A solution for distinguishing Le(a−b−) sera in CA19-9 assays using SphereLight 180 and Architect i2000 assays

► We made cut-off solution and discriminate of Le(a−b−) by measuring CA199. ► The SphereLight 180 and Architect i2000 of five commercially available kits were able to be discriminated. ► The distribution of CA199 was different according to the difference of Lewis Blood type.