RETROSPECTIVE STUDY CORRELATION BETWEEN GRADE AND AMOUNT OF MITOSIS WITH ER, PR, AND HER2 EXPRESSION IN INVASIVE BREAST CARCINOMA OF NO SPECIAL TYPE

Abstract

Background: In 2018 there were about 24.2% new cases of breast carcinoma worldwide. Molecular breast carcinoma, like expression estrogen receptor (ER), progesterone receptor (PR), and Human Epidermal Growth Factor Receptor2 (HER2) have a higher sensitivity than morphological feature, like tumour grade and mitotic count as prognostic factors. The grade of the tumor reflects how similar these cells are to normal breast epithelial cells. The dominant growth pathway in normal breasts predominantly involves ER and PR, so tumours with ER and PR positivity show lower grade and proliferation activity. In contrast, tumours with ER and PR negativity often have more severe mutation, like overexpression of HER2. Objective: To analyze the correlation between grade and mitotic count with ER, PR, and HER2 expression. Methods: Analytical observational study with a retrospective design. This study used medical record data from ER, PR, and HER2 immunohistochemical examinations as well as histopathological grade and mitotic data for invasive breast carcinoma of no special type in the Anatomical Pathology Laboratory of Dr. Soetomo Surabaya for the period January 1, 2017 - December 31, 2019. Furthermore, the analysis of the relationship between grade and mitotic count was carried out with the expression of ER, PR, and HER2. Results: There was a significant negative relationship between grade and ER with rs = -0.170 (p = 0.000), the number of mitosis and ER with rs = -0.010 (p = 0.001), grade and PR with rs = -0.168 (p = 0.000), and the number of mitosis and PR with rs = -0.110 (p = 0.000). There was no significant relationship between grade and HER2 (p = 0.470) and the number of mitosis and HER2 (p = 0.279). Conclusion: There is a negative significant relationship between grade and amount of mitosis with ER and PR expression. There is no significant relationship between grade and amount of mitosis with HER2 expression.