RAI2 and neoplasm: Though no association was found between RAI2 expression and clinical characteristics such as gender, TNM stage, lymph node metastasis, age, differentiation, tumor location, and size (P >0.05) (Table 1), Kaplan-Meier analysis indicated that low expression of RAI2 was significantly associated with poor 5-year RFS (P = 0.0029) and 5-year OS (P = 0.0102) (Figure 4B).