To this effect, pure DCIS samples had significantly higher FOXP3+ CA9+ colocalization (p = 0.0007, Fig. 4a) as well as abundance of CA9+ (p = 2.3e–9) and FOXP3+ cells (p = 4.4e–6, Fig. 4c), compared to synchronous DCIS regions. This evidence concerns the gene CA9 and ductal breast carcinoma in situ.