Correlation between the Her-2eu Status as Determined by Immunohistochemical Analysis and the Serum Her-2eu Concentration as Determined by the Use of ADVIA Cencaur? Automated Immunoassay in Breast Cancer Patients

摘要

Purpose Serum Her-2eu is extracted from the extracelluar domain of the Her-2eu tyrosine kinase to serum. We evaluated the correlation between the Her-2eu status as determined by immunohistochemical analysis (IHC) and the serum Her-2eu concentration in a population of Korean women with breast cancer. Methods Serum Her-2eu levels were examined from 254 female patients with primary breast cancer and 38 patients with metastatic breast cancer. Serum Her-2eu levels were measured by the use of a chemiluminescence immunoassay (ADVIA centaur? system) during the preoperative period. The level of Her-2eu in all of the breast cancer tissue samples was determined by IHC, and samples with an IHC grade +2 were subject to fluorescence in situ (FISH). When tissue samples exhibited IHC grade +3 or showed amplification of Her-2eu as determined by FISH analysis, Her-2eu was considered overexpressed. The cut-off value for serum Her-2eu level was 10.2 ng/mL. Results The mean serum Her-2eu level was 10.1 ng/mL in primary breast cancer samples. The serum Her-2eu concentration significantly correlated with expression of Her-2eu as determined by tissue IHC analysis (grade 1/3, 9.33±1.7 ng/mL; grade 2/3, 8.89±1.6 ng/mL; grade 3/3, 12.37±4.0 ng/mL, p Conclusion Serum Her-2eu appears to be correlate with tissue Her-2eu expression in primary and metastatic breast cancer where Her-2eu is overexpressed. Further studies to determine levels of serum Her-2eu are required to determine cuttoff values and the clinical application of the finding for breast cancer patients in Korea.