Kawasaki et al. reported that the Ki-67 labeling index of nonneuroendocrine DCIS (8.1%) was significantly higher than that of neuroendocrine DCIS (4.3%), and they concluded that a low Ki-67 labeling index is correlated with a good prognosis in patients with neuroendocrine DCIS [20]. This evidence concerns the gene MKI67 and ductal breast carcinoma in situ.