NKX2-1 and neoplasm: Based on the categories defined above, the expression status of NKX2.1 correlated significantly with age (P = 0.002), tumor size (P = 0.004), depth of tumor infiltration (T stage, P <0.001) and TNM stage (P <0.001) but not with gender (P = 0.861), local lymph node metastasis (N stage, P = 0.325) or distant metastases (M stage, P = 0.612).