Although the rate of DCIS recurrence was higher for cases with HER2/neu+/Ki67+ DCIS (13/51 (26%) compared with 13/162 (8%) for cases without this profile, P=0.0009), we could not determine the effect of Ki67 positivity in the presence of HER2/neu positivity, because the majority (51/58) of HER2/neu+ cases were Ki67+. This evidence concerns the gene MKI67 and ductal breast carcinoma in situ.