|M.Sc Student||Mzalbat Raneen|
|Subject||Comparison between HER2 Extracellular Domain in Serum and|
HER2 Overexpression in Breast Cancer Tissue
|Department||Department of Medicine||Supervisor||Mr. Jamal Zidan|
|Full Thesis text|
Background: Immunohistochemistry (IHC), fluorescent in situ hybridization (FISH) and chromogenic in situ hybridization (CISH) are reliable ways to identify human epidermal growth factor receptor 2 (HER2) and HER2 amplification. Each technique requires access to tumor tissue and high-quality tissue sample, which may not be available in some patients. HER2 extracellular domain (ECD) may be shed to the serum. The importance of serum ECD in breast cancer (BC) is not yet determined. The first aim of this study was to explore the correlation between serum ECD and tissue HER2 expression. The second aim was to compare ECD levels with clinical and pathological features in early BC patients .
Patients and methods: This prospective trial included patients with stage I-III BC. Serum HER2 ECD levels were measured by ADVIA Centaur automated assays before surgical resection of the tumor. Tissue HR2 status was detected by IHC in all tumors. CISH test was utilized in HER2: 2 tumors by IHC. Serum ECD >15ng/ml was considered to be positive
Results: 80 patients with breast tumors were included in this study. Stage I-III BC was diagnosed in 64 patients, Ductal carcinoma in situ in 9 patients and benign tumors in 7 patients. HER2-positive status in tumor tissue was observed in 8 of 64 patients with (16.4%). Mean value of serum ECD was 10.9 ng/ml (range: 6.7 to 21.5). No significant relationship between ECD and tissue HER2 was found. ECD was significantly higher in women aged > 40 than in women aged < 40. No significant relation was found between ECD and other variables; tumor size, stage, histological grade, lymph node involvement, estrogen (ER) and progesterone (PR) receptors .
Conclusions: The sensitivity of HER2 ECD for the diagnosis of HER2 positive primary breast cancer is poor. No significant correlation was found between ECD levels and HER2 expression in breast cancer tissue, clinical and pathological characteristics of BC patients.