Analysis of CD8+ and CD4+ cells in oral squamous cell carcinoma and their association with lymph node metastasis and histologic grade of malignancy.

This study aimed to analyze CD8 and CD4 cells in oral squamous cell carcinoma and to correlate it with prognostic indicators. The sample was composed of 50 cases. Clinical data and histologic grade of malignancy were obtained. Specimens were submitted to immunohistochemistry. Cells were counted in 10 fields at the tumor invasion front and expressed as median. CD8 cells were more frequent in nonmetastatic lesions (18.5) and in low-grade specimens (18.2) (P<0.05). CD4 cells were equally distributed in nonmetastatic and metastatic lesions (4.5). In addition, they were slightly more frequent in low-grade lesions (4.7). None of these correlations were significant (P>0.05). CD8/CD4 ratio was higher in cases without metastasis (3.57) and in low-grade lesions (3.62) (P>0.05). Probably, CD8 cells are the most effective and important cells in the host immune responses against oral squamous cell carcinoma. In addition, CD4 cells could indirectly influence the host protection through regulation of CD8 recruitment and activation.