Using the second validation set of samples composed of 120 cases of DCIS and invasive carcinoma (60 cases in each), difference in CXCL10 mRNA expression was examined between DCIS and invasive carcinoma in the whole groups, in HR-positive subgroup, as well as in HR-negative subgroup (Fig. 1A). The gene discussed is CXCL10; the disease is ductal breast carcinoma in situ.