MIF levels in both serum and plasma were not different between CIS patients and healthy controls (Fig. 4A and Supporting Information Fig. 3A) or high‐risk and low‐risk CIS subgroups (Fig. 4B and Supporting Information Fig. 3B), and did not correlate with CXCR4 and CD74 expression levels on B cells from the same individuals (Supporting Information Fig. 3C and D). This evidence concerns the gene MIF and in situ carcinoma.