Abstract
BACKGROUND: As dendritic cells (DCs) are the major antigen-presenting cells of the immune system, understanding their role in esophageal cancer is essential for the development of preventative and treatment strategies. This study investigated the expression level and clinical value of tumor infiltrating dendritic cells (TIDCs) in tumor tissues of patients with esophageal cancer. METHODS: From January 2019 to January 2021, 184 patients with esophageal cancer treated were prospectively enrolled as the observation group and 184 patients with benign esophageal tumors were selected as the control group. Tumor tissue samples were obtained and the expression level and phenotypes of the TIDCs were analyzed. The correlation between TIDC expression and clinical characteristics of patients with esophageal cancer was investigated. RESULTS: The density of the TIDCs in the observation group was lower than that in the control group (8.76±2.25 vs. 9.97±2.19; P=0.000). Furthermore, the percentage of major histocompatibility complex-II (MHC-II) positive DCs and the percentage of CD54 positive DCs were relatively lower in the observation group compared to the control group (6.60%±2.12% vs. 9.34%±2.41%; P=0.000 and 7.41%±2.36% vs. 9.98%±2.47%; P=0.000, respectively). Esophageal cancer patients with lymph node metastasis had lower TIDC density, lower percentage of MHC-II positive DCs, and lower percentage of CD54 positive DCs compared to patients without node metastasis (P<0.05). Patients with stage III esophageal cancer also showed significantly lower TIDC density, lower percentage of MHC-II positive DCs, and lower percentage of CD54 positive DCs compared to patients with stage I/II esophageal cancer (P<0.05). Esophageal cancer patients with tumor diameter ≥4 cm presented with decreased TIDC density, decreased percentage of MHC-II positive DCs, and decreased percentage of CD54 positive DCs compared to patients with tumor diameter <4 cm (P<0.05). In addition, the density of TIDCs, the percentage of MHC-II positive DCs, and the percentage of CD54 positive DCs were significantly negatively correlated with the percentage of CD4(+) T-lymphocytes and positively correlated with the percentage of CD8(+) T-lymphocytes (P<0.05). CONCLUSIONS: Patients with esophageal cancer had low expression and function of TIDCs, and this was related to the imbalance of T-lymphocyte subsets, lymph node metastasis, TNM stage, and lesion size.