Comparison of Magnetic Resonance Imaging Findings of Neuroendocrine and Non-neuroendocrine Ductal Carcinoma in Situ of the Breast

: Neuroendocrine ductal carcinoma in situ of the breast （ NE-DCIS ） was recently recognized as a special subtype of DCIS, although the diagnostic criteria for NE-DCIS are yet to be established. DCIS is defined as the immunohistochemical expression of neuroendocrine markers chromogranin A and / or synaptophysin in over 50 ％ of tumor cells. Here, we investigated whether there are significant differences in magnetic resonance imaging （ MRI ） findings between NE-DCIS and non-NE-DCIS. The study sample comprised 8 lesions in 7 patients with breast NE-DCIS and 71 lesions in 69 patients with non-NE-DCIS who underwent preoperative MRI and histopathological diagnosis at our hospital from June 2010 to June 2012. The patients were females aged 34 – 85 years. We examined the lesion type, pattern of time-signal intensity curve （ TIC ） on dynamic contrast-enhanced MRI （ DCE-MRI ） , presence or absence of bloody duct ectasia delineation, and presence or absence of calcification on mammography （ MMG ） . Mass-type lesions were significantly more common in breast NE-DCIS than in non-NE-DCIS on MRI. On DCE-MRI, the TIC washout pattern was more commonly observed in NE-DCIS than in non-NE-DCIS, and although there was no significant difference in the rate of bloody duct ectasia delineation, it was relatively more common in NE-DCIS. MMG revealed a significant difference in calcification between non-NE-DCIS （ 60.1 ％） and NE-DCIS （ 0 ％） . Mass-type lesions TIC washout pattern non-NE-DCIS on MRI and DCE-MRI.