MMP11 and ductal breast carcinoma in situ: Only the expression of COL10A1 and MMP11 was found to progress from ‘low expression’ in pDCIS, to ‘intermediate expression’ in DCIS and ‘high expression’ in the corresponding IBC, the difference between pDCIS and DCIS (of DCIS/IBC mixed tumours) being significant (P < 0.05; Fig. 4).