CCNB1 and ductal breast carcinoma in situ: The expression of Ki67 (P = 0.010), CCNB1 (P = 0.007) and MYBL2 (P = 0.023) in the proliferation group and the expression of MMP11 (P < 0.001) and CTSL2 (P = 0.010) in the invasion group were all significantly lower in the IDC/DCIS group than in the IDC group.