Background. The most common malignant epithelial tumor originating from the colon is adenocarcinoma, which accounts for >90% of all colon carcinomas. Tumor-infiltrating lymphocytes (TILs) have been extensively studied and are associated with prognostic factors for several solid tumors. Research of TILs with CD3 immunohistochemistry staining for colonic adenocarcinoma is still rarely done until now. Objective. the correlation of CD3 immunohistochemical expression with the degree of Tumor-Infiltrating Lymphocytes (TILs) intratumoral and histopathological grading of adenocarcinoma colon. Materials and Methods. Analytical study with a cross-sectional approach using slides and paraffin blocks of colon adenocarcinoma patients with CD3 immunohistochemical staining. Statistical analysis was performed with Chi-Square and Eta. to see the relationship of intratumoral TILs with histopathological grading of colon adenocarcinoma. Results. It was found in this study that the most were low-grade adenocarcinoma of the colon as many as 28 cases (87.5%) and the least was high-grade adenocarcinoma of the colon as many as 7 cases (21.9%). The degree of intratumoral TILs in this study was found in 32 cases (100%). In CD3 immunohistochemistry staining, 25 positive results (78.1%) and negative results in 7 cases (21.9%), Chi-Square test was carried out on the correlation grading with CD3 display, p-value = 0.201 (p>0.05). While the correlation between the degree of TILs with CD3 immunohistochemical expression using the Eta test obtained p-value = 0.05 (p> 0.05). Conclusion. There is no effect of histopathological grading with CD3 immunohistochemical expression and there is a significant relationship between the number of degrees of intratumoral TILs and CD3 immunohistochemical expression with a strong correlation and a positive direction.

TILs

CD4+

lymphocyte

immunohistochemical