EP1.04-14 Effects of FoxP3-Positive Regulatory T Cell on Lymphoid Follicle Formation of Patient with Lung Squamous Cell Carcinoma

We have reported that lymphoid follicle formation by tumor infiltrating lymphocytes (TILs) is a negative predictor of patients with lung squamous cell carcinoma (SCC) following surgery. However, the role of FoxP3-positive regulatory T cells on lymphoid follicle formation and survival is still unclear Specimens obtained from patients during resection of lung SCC were examined for lymphoid follicle formation and immunohistochemistry of TILs. Appearance of CD3/25/FoxP3-triple positive regulatory T cell was correlated with lymphoid follicle formation (p=0.001). Univariate analysis showed that pathological stage (p=0.037), lymphoid follicle formation (p=0.007), pleural invasion (p=0.025), vascular invasion (p=0.013), and appearance of CD3/25/FoxP3-triple positive regulatory T cell (p=0.097) were correlated with overall survival. Multivariate analysis revealed that lymphoid follicle formation (p=0.042) and pleural invasion (p=0.040) were independent prognostic factors related to overall survival, whereas CD3/25/FoxP3-triple positive regulatory T cells were not. Appearance of CD3/25/FoxP3-triple positive regulatory T cell was correlated with lymphoid follicle formation. Lymphoid follicle formation, rather than appearance of CD3/25/FoxP3-triple positive regulatory T cell, is a predictor of patient survival following surgery for lung SCC.