BUB1 and neoplasm: By non-parametric Spearman rank correlation analysis, the frequency of BUB1 expression showed a significant correlation with tumor stage (p < 0.001, r = -0.295), nodal status (p = 0.027, r =-0.15), the presence of distant metastases (p = 0.006, r =-0.184), UICC stage (p < 0.001, r = -0.316) and resection margin (p = 0.038, r = -0.141) (Table 1).