Correlation Among Tumor Size, Histopathological Grade and the Expression of RAC1 Protein with Breast Cancer Metastasis to Ipsilateral Axillary Lymph Nodes

Abstract

Breast cancer (BC) is the most common cancer affecting women worldwide. Mastectomy is the standard treatment for breast cancer. The purpose of axillary lymph nodes (ALN) dissection in mastectomy is to examine the status and the presence of metastasis in ALN. This study is an analytic observational cross-sectional study coupled with a categorical comparative study in 60 BC patient’s with- and without-ALN metastasis. The data that used in this study were histopathological data from patients medical record and immunohistochemistry (IHC) of RAC1 expression data. The immunohistochemistry was performed with a cutoff point based on the result of a receiver operating characteristics (ROC). This study combined BC tumor size, histopathological grade, and expression of RAC1 protein in correlation with known risk factors on metastasis to ALN. From 60 subjects, there were 63.3 % (38) ALN (+) and 36.7 % (22), ALN (−). BC of T2 tumor size, grade 2 and RAC1(−), the ALN metastasis chance was 0.6 %. T2 tumor size, grade 2 and RAC1(+), the ALN metastasis chance was 4.5 %. T2 tumor size, grade 3 and RAC1(−), the ALN metastasis chance was 3.0 %. T2 tumor, grade 3 and RAC1(+), the ALN metastasis chance was 18.8 %; T3 tumor size, grade 3 and RAC1(−), the ALN metastasis chance was 12.7 %. T3 tumor size, grade 3 and RAC1(+), the ALN metastasis chance was 52.2 %; T4b tumor size, grade 3, RAC1(−) and RAC1(+), the ALN metastasis chance was 40.8 and 83.8 %, respectively. We conclude that smaller tumor size and lower histopathological grading with RAC1(−) has lesser possibility to ALN metastasize. HIGHLIGHTS Breast cancer (BC) is a malignant neoplasm originating from epithelial cells of the ducts and breast glands in the area of the lobules and terminal ducts known as the terminal duct lobular unit (TDLU) and the surgery performed is breast-conserving treatment or mastectomy that examine the status and the presence of metastasis in ALN RAC1 is a member of the RHO-GTPase family that plays an important role in the migration process, loss of adhesions between cells, and tumor metastasis also found in BC so it was used as parameter in this study Tumor size, histopathological grading, and the expression of RAC1 protein has correlation with with BC metastasis to the axillary lymph nodes that the smaller the tumor size, the lower the histopathological grading with RAC1(-) GRAPHICAL ABSTRACT