We found an increase in staining intensity for SPP1 in DCIS samples compared to healthy controls, which confirms a study by Oyama et al., who detected positive staining of SPP1 using immunohistochemistry on paraffin-embedded tissues in most cases of low-grade cribiform and high-grade comedo-type ductal carcinoma in situ [31]. This evidence concerns the gene SPP1 and ductal breast carcinoma in situ.