Multiple markers presented differences in between-sample divergence between pure DCIS and synchronous DCIS samples, with the latter showing increased divergence for GLUT1 (p = 0.01), FOXP3 (p = 0.01), and HER2 (p = 0.04) staining, but decreased divergence of ER (p = 0.01) staining (Fig. 3B, Supplementary Fig. S3, Pairwise Mann–Whitney U tests, unadjusted p values). Here, ERBB2 is linked to ductal breast carcinoma in situ.