The Significance of Tumor-infiltrating Lymphocytes (TILs) in Histopathological Grading of Invasive Breast Carcinomas

Breast cancer is the leading cause of cancer death in women worldwide with high incidence rate. Invasive breast carcinoma is the most common form of breast cancer. Prognosis and survival rate of the patient is related with histopathological grading of the invasive breast carcinoma. Tumor-infiltrating lymphocytes (TILs) have been reported to be associated with patient clinical outcomes in a number of different malignant tumors. We studied the expression of TILs in invasive breast carcinoma using Hematoxylin Eosin (HE) staining. We studied the expression of are tumor-infiltrating lymphocytes (TILs) in paraffin block of tissue biopsy from breast tumor specimens. Immunohistochemistry was used to assess the expression of TILs in tumor breast tissue from 80 samples. Univariate and bivariate analyses assessed outcomes according to the expression of TILs in different histopathological grading. Of the 80 tumor specimens, 36 (45 %) of samples have high grade of TILs and 44 (55 %). On bivariate analysis, there were significant differences in the expression of TILs lymphocytes between well, moderately and poorly differentiated invasive breast carcinoma, respectively (p< 0.0001). As a conclusion; we found that the severity of invasive breast carcinoma differentiation is directly related to the degree of TILs expression.