Evaluation of CD4+ tumor‑infiltrating lymphocyte association with some clinicopathological indices of oral squamous cell carcinoma

Abstract

Background: The delayed diagnosis of oral squamous cell carcinoma (OSCC) affects therapeutic and prognostic strategies, and provides regional recurrence or distant metastasis. The tumor‑infiltrating lymphocytes (TILs) are known as a critical diagnostic biomarker in antitumor immune response. We evaluated the association between CD4+ T‑lymphocyte marker, some clinicopathological indices, and the impact of TILs on the stage and grade of OSCC. Materials and Methods: In this cross‑sectional study, 37 OSCC specimens including 16 early and 21 advanced stages (categorized base‑on recent clinical oncology references) and their related healthy surgical margin (as internal control group) were collected. Obtained histochemical data were analyzed by SPSS V.23 software. The expression of CD4+ marker in tumor microenvironment (TME) was compared by nonparametric Mann–Whitney and Kruskal–Wallis as well as Fisher’s exact tests. P < 0.05 was remarked statistically significant. Results: The low‑grade patients represented more CD4+ TIL that was statistically significant (P = 0.011). However, there was no statistically significant difference in CD4+ TIL between various stages (P = 0.404), tumor size, and lymph node involvement (P > 0.05). Moreover, there was no significant relation between TIL infiltration, age, and tumor localization (P > 0.05), however CD4+ expression in women was more than men (P = 0.008). The CD4+ T‑lymphocyte infiltration in TME was more significant than healthy surgical margin (P < 0.001). There was a statistically significant difference between healthy surgical margin and different grades and stages of OSCCs that lower grades demonstrated more CD4+ TIL infiltration (P < 0.001). Conclusion: The CD4+ T‑lymphocytes may play important role in differentiation and maturity of epithelial cell, tumorigenesis, and progression of OSCC. Key Words: CD4+ T‑lymphocyte, diagnosis, oral cancer, prognosis, tumor‑infiltrating lymphocyte