Down-regulation of DMBT1 expression in the cancerous lesions compared to the normal and/or hyperplastic epithelium was statistically significant for both, ductal carcinoma in situ (DCIS) (1/10 versus 33/42 normal and/or hyperplastic epithelia; p = 0.0001) and invasive carcinoma (IC) (2/45 versus 33/42 normal and/or hyperplastic epithelia; p < 0.0001). Here, DMBT1 is linked to ductal breast carcinoma in situ.