Clinicopathological value of epidermal growth factor receptor (EGFR) and Ki-67 expression in colorectal adenoma and adenocarcinoma

Objective: To evaluate epidermal growth factor receptor and Ki-67 immunohistochemical expression in colorectal adenoma and carcinoma cases, and to relate their expression with the available clinicopathological data. Methods: The retrospective study was conducted at the Faculty of Medicine, Kafrelsheikh University, Egypt, from September 2019 to October 2020, and comprised formalin-fixed and paraffin-embedded specimens related to cases of colorectal adenoma and those of colorectal carcinoma, who had no previous radiation or chemotherapeutic treatment. Immunohistochemical staining of all the cases was done using anti-epidermal growth factor receptor and anti-Ki-67 antibodies. Data was analysed using SPSS 20. Results: Of the 70 cases, 20(28.5%) were of colorectal adenoma; mean age 52.95 +/- 13.47 years, and male-to-female ratio 1:1. The remaining 50(71.5%) cases had colorectal carcinoma; mean age 51.08 +/- 13.49 years, and male-to-female ratio 1.17:1. Epidermal growth factor receptor and Ki-67 overexpression related significantly to villous histopathological type and high-grade dysplasia in colorectal adenoma cases (p<0.05). In colorectal carcinoma cases, epidermal growth factor receptor overexpression related significantly to tumour grade (p<0.05). Ki-67 overexpression related significantly to increased pathological stage (p<0.05). Conclusions: Overexpression of epidermal growth factor receptor and Ki-67 was found to be an ominous sign of colorectal adenoma aggressiveness, and the risk of progression to colorectal carcinoma.