Application of Tissue Microarray Technology to detect expression of Ki-67 in breast carcinoma patients

Abstract

Breast cancer is the most common cancer of women worldwide. It is a heterogeneous disease. The incidence rate of this disease increased in the last years in Iraq. The current study was conducted to study the immunohistochemical for the breast tumors by using tissue microarray (TMA) technique. The mean age of the Iraqi breast cancer patients in our study was (50.32±11.85) years old; ranging from 23-80 years old.Formalin-fixed, paraffin-embedded (FFPE) samples were used in this study. Two TMAs recipient blocks were designed and constructed for samples.Both two TMAs contain 30 samples of Iraqi breast cancer patients and normal kidney tissue for control. Each donor sample were represented in duplicate, cores were transferred from each donor patient sample to the recipient block, sections from the sample slides cutting and potted on charge slide then stained these sections with hematoxylin and Eosin (H and E) stained then immunohistochemically (IHC) studied for Ki-67 for the TMAs. The results showed that 35 out of 60 cases was positive expression for Ki-67, and the most cases were grade II for expression all of Ki-67. While results of positive lymph node status were found in 19 cases out of 35 was positive expression for Ki-67. The study revealed that there was a significant relationship between the Ki-67 and histological grade and lymph node status. The results indicated that the Iraqi breast cancer cases used in this study were phonotypical more aggressive. We utilized TMA sections for the validation of the Ki-67. In conclusion, TMA was successfully used as a rapid, economic and effective method for IHC studies.