Prognostic Impact of CD8+ and CD4+ Tumor-Infiltrating Lymphocytes and Perineural/Vascular Invasion in Laryngeal Squamous Cell Carcinoma.

Abstract

Background & objective: Squamous cell carcinoma (SCC) is characterized by infiltration of CD4+ and CD8+ T lymphocytes, which represent an early host immune response against malignant cells. This immune response may inhibit tumor progression and suppress malignancy. This study aimed to evaluate the density of CD4+ and CD8+ lymphocytes and their ratio within tumor nests and surrounding stroma in conventional laryngeal SCC. It also examined associations with prognostic factors such as regional lymph node metastasis, tumor histologic differentiation, vascular invasion, and perineural invasion.

Methods: This retrospective study analyzed 54 laryngeal SCC samples from patients who underwent total laryngectomy and cervical lymph node dissection without prior neoadjuvant chemoradiation therapy. Immunohistochemistry was used to assess CD4+ and CD8+ T lymphocytes in tumor nests and surrounding stroma. Statistical analyses evaluated correlations between lymphocyte infiltration and prognostic factors, including lymph node metastasis, histologic differentiation, vascular invasion, and perineural invasion.

Results: A significant association was found between high intratumoral CD8+ T lymphocyte density and a lower incidence of vascular and perineural invasion (mean, 10.9 cells/HPF vs 4.5 cells/HPF; p = 0.03). No significant correlations were observed between lymphocyte density and lymph node metastasis or tumor histologic differentiation.

Conclusion: High intratumoral CD8+ T-cell infiltration correlates with reduced vascular and perineural invasion in laryngeal SCC, suggesting a protective role in limiting tumor invasiveness. These findings highlight the prognostic significance of CD8+ T lymphocytes and warrant further research into immune mechanisms affecting SCC progression and patient outcomes.