Immunohistochemical expression of tumor-infiltrating lymphocytes CD8 and FOXP3 in invasive ductal carcinoma of breast

Tumor-infiltrating lymphocytes (TILs) in breast cancer primarily comprise CD8+ T cells, which have anti-tumor properties, and FOXP3+ regulatory T cells (Tregs), which act as immune regulators. Both of these lymphocyte types play a significant role in breast cancer immunity. Understanding the relationship between TIL levels and the balance between CD8+ and FOXP3+ T cells is crucial for breast cancer management. Despite the growing recognition of their importance, the precise role and impact of these immune cells remain controversial and not fully understood. Evaluating the infiltration of CD8+ T cells and FOXP3+ Tregs in breast cancer tissues, as well as their correlation with tumor characteristics, can provide valuable insights into their prognostic value and their impact on cancer progression. Such a study has not yet been reported in India. Therefore, this study explores the connection between TILs, FOXP3/CD8, and various clinicopathological parameters, aiming to better understand these relationships and improve prognostic models and personalized immunotherapy for breast cancer patients. To evaluate the immunohistochemical expression of TILs, CD8, and FOXP3 in invasive ductal carcinoma of the breast and analyze their association with clinicopathological parameters. Ninety-six histologically proven cases of Infiltrating ductal carcinoma (IDC) Breast were studied. Age, Laterality, tumor size, TNM stage, lymph node metastasis, histological grade, ER, PR, HER2neu, and Ki67 status were done. Both intensity and proportion of CD8 and FOXP3 expression were recorded. For qualitative data, the Chi-square test was used as a test of significance. The p-value (probability that the result is true) of < 0.05 was considered statistically significant after assuming all the rules of statistical tests. There was an inverse correlation between CD8+ and FOXP3+ TILs (Pearson = − 0.508, p = 0.002), and a positive correlation between CD8+ TILs and overall TIL levels (Pearson = 0.419, p < 0.001). FOXP3+ TILs strongly correlated with a higher FOXP3/CD8 ratio (Pearson = 0.751, p < 0.001). These results suggest that higher CD8+ TILs are linked to robust anti-tumor immunity, while increased FOXP3+ TILs indicate an immunosuppressive environment. These insights highlight the importance of TIL balance in breast cancer prognosis and therapy. This study investigated links between clinical and tumor immunity, spotlighting CD8 and FOXP3 and their ratio. The immunohistochemical analysis of tumor-infiltrating lymphocytes CD8 and FOXP3 in invasive ductal carcinoma of the breast reveals crucial insights into the tumor microenvironment. These findings highlights the potential of immune markers not only in refining prognostic models but also in guiding personalized immunotherapeutic approaches for breast cancer patients.