The significance of CD4+ and CD8+ T lymphocyte infiltration in esophageal squamous cell carcinoma

To investigate the relationship between the abundance of CD4+ and CD8+ T cells in the tumor microenvironment and the prognosis of patients with esophageal squamous cell carcinoma, and to analyze their correlation and explore its clinical value. In total, we enrolled 120 cases of esophageal squamous cell carcinoma diagnosed. The abundance of CD4+ and CD8+ T lymphocytes in the tissue specimens of esophageal cancer was examined by immunohistochemistry. We measured the correlation between the abundance of CD4+ and CD8+ T lymphocytes and the clinical and pathological characteristics and prognosis of esophageal squamous cell carcinoma. The tissue abundance of CD4+ T lymphocytes was closely related to tumor prognosis (P < 0.05). Similarly, there was a statistically significant relationship between the tissue abundance of CD8+ T lymphocytes and patients' prognosis (P < 0.05), indicating that a high abundance of CD8+ T lymphocytes predicts better prognosis in esophageal squamous cell carcinoma. Surprisingly, we found that a higher CD4+/CD8+ ratio predicted a better prognosis of esophageal squamous cell carcinoma. The tissue abundance of CD4+ and CD8+ T lymphocytes can serve as an important indicator for predicting the long-term survival of patients with esophageal squamous cell carcinoma. A high CD4+/CD8+ ratio may improve patients' prognosis through several pathways. The association of this ratio with clinical and pathological characteristics may explain the poor efficacy of immunotherapy in patients with esophageal cancer. These findings may help us find new targets for immunotherapy by exploring the immune microenvironment of esophageal squamous cell carcinoma.