Hubungan Ekspresi Imunohistokimia Human Epidermal Growth Factor Receptor 2 (HER2) dengan Grading Histopatologi, Kedalaman Invasi Tumor, Keterlibatan Kelenjar Getah Bening, dan Invasi Limfovaskular pada Adenokarsinoma Kolorektal

Abstract

Background : Colon cancer is the fourth most common cancer in the world, while rectal cancer is the seventh most common cancer in the world. Histopathologically, about 90% of colorectal carcinomas are colorectal adenocarcinomas. Researches to identify biologic markers and potential target therapies in patients with colorectal carcinoma are increasingly being carried out. One of them is anti-Human Epidermal Growth Factor Receptor 2 therapy (anti-HER2 therapy). The HER-2 gene is a protooncogene belonging to the HER family that has been found to be elevated in several malignancies. Reports of increased HER2 expression in colorectal carcinoma are still very varied with a fairly wide range of values, namely 3%-65%. The role of HER2 in colorectal carcinoma is unclear, and its relationship to the grading and prognosis of colorectal carcinoma is not well understood. Some studies report that positive HER2 expression is associated with poor grading and survival rates, but other studies do not confirm these findings. These studies have also reported different results regarding the association of HER2 expression with various clinicopathological features of colorectal carcinoma, such as age, tumor location, tumor size, lymph node involvement, and tumor stage. Objective : To analyze the relationship of HER2 immunohistochemical expression with histopathological parameters specific to grading, depth of tumor invasion, lymph node involvement, and lymphovascular invasion in colorectal adenocarcinoma. Materials and Methods : This study is an analytical study with a cross-sectional approach on 45 surgical samples diagnosed as colorectal adenocarcinoma and then performed with Human Epidermal Growth Factor Receptor 2 (HER2) immunohistochemical staining. The data obtained in the study were processed with the help of statistical software and the relationship of the immunohistochemical expression of Human Epidermal Growth Factor Receptor 2 (HER2) with specific histopathological parameters grading, depth of tumor invasion, lymph node involvement, and lymphovascular invasion in colorectal adenocarcinoma was carried out by statistical tests. Result : There is a significant relationship between HER2 and histopathological grading with p value = 0.012 (p <0.05). There was no significant relationship between HER2 and the depth of tumor invasion (p=0.485), lymph node involvement (p=0.294), and lymphovascular invasion (p>0.05).