Evaluation of tumor-infiltrating T & B lymphocytes and their association and distribution in oral squamous cell carcinoma tumor microenvironment: An in vitro immunohistochemical study

Objective. The immune interaction between host immunity and the tumor microenvironment is complex, and a thorough under-standing of tumor-infiltrating lymphocyte selection in oral cancer, including T and B cells, is urgently required. Within the tumor microenvironment, tumor cells escape immune surveillance and grow uncontrollably. The study examined the relationship and distribution of tumor-infiltrating T and B lymphocytes.Study Design. Retrospective data of paraffin-embedded tissue samples of 47 primary oral squamous cell carcinoma (OSCC) cases were retrieved. Hematoxylin and eosin evaluation, along with all clinicopathologic data, were collected. Immunohistochemical CD3 and CD20 markers were used and evaluated for association and distribution in given OSCC cases.Results. The intermediate type of inflammatory infiltrate was seen primarily in Well DIfferentiated Squamous cell Carcinoma grade and positive and negative lymph nodes. Compared with T-cell density, B-cell density showed an aggregate pattern rather than a scattered pattern, indicating a statistically significant association between T-cell and B-cell infiltrate. B-cell infiltrates were also found to have a statistically significant relationship with tertiary lymphoid structure.Conclusions. A strong, positive association and correlation exists between B-and T-lymphocyte infiltration in both the stroma and the invasive front. When compared with T-cell density, B-cell density is more predominantly in aggregates.