SDC1 and breast ductal adenocarcinoma: Our study determined that the stroma of the metastatic IDC showed an overall Sdc1 expression in 53.4% of the lymph nodes (i.e., it was absent in almost half of them or 46.7% (Table 3)), which is lower (but not statistically significant) than the expression in the stroma of the primary ductal carcinomas (73.3%).