Assessment of tumor-associated immune cells in laryngeal squamous cell carcinoma.
Objective: This study investigated the characteristics of tumor-associated immune cells (TAICs) in laryngeal squamous cell carcinoma (LSCC) and their correlation with clinicopathological variables.
Methods: The immune cell infiltrates of 71 specimens of stages I-IV LSCC were examined. The density of TAICs expressing CD3, CD4, CD8, CD68, and CD163 was assessed using immunohistochemical staining and image analysis in peritumoral and intratumoral regions.
Results: Higher densities of CD3+ and CD8+ cell and lower densities of CD68+ and CD163+ cell infiltrations were found in early tumor stages than in late tumor stages. A higher percentage of patients with strong CD3+ and CD8+ immune cell infiltration and weak CD68+ cell infiltration in both tumor regions presented with T1 stage tumors compared with T4 stage tumors. Further, strong CD68+ cells infiltration in both regions was observed in a greater number of patients who had a relapse, while a weak CD3+ cells infiltration in both regions was found in a greater number of patients with nodal lymphatic metastasis. The univariate analysis showed that a high density of peritumoral CD3+ and CD8+ immune cells in both regions was significantly associated with a favorable overall survival (OS) (P = 0.004; P = 0.006; P = 0.042). In contrast, a high density of intratumoral CD68+ cells and peritumoral CD163+ cells was significantly associated with poor OS durations (P = 0.026; P = 0.030). The multivariate analysis demonstrated that a high density of peritumoral CD163+ cells correlated with poor OS after adjusting for tumor stage, recurrence, and nodal lymphatic metastasis (P = 0.034). This study found different patterns of TAIC infiltration in LSCC. The density and location of TAICs infiltration correlated with the clinicopathological characteristics of LSCC.
Conclusions: A combined analysis of the density of TAICs and their location may help predict patient survival and response to checkpoint inhibitors.