Metaplastic carcinoma of the breast with neuroglial differentiation.

We present a case of a 34-year-old female who had a rapidly enlarging right breast mass. Biopsy results were consistent with a neuroblastic neoplasm of the breast. Neoadjuvant chemotherapy for a neuroblastoma was performed followed by a modified radical mastectomy was performed. Final pathology revealed small foci of poorly differentiated carcinoma randomly distributed within extensive areas of neuroglial differentiation. Such a lesion has not been described in the current literature to our knowledge, and we propose that this neoplasm is a metaplastic carcinoma with a novel heterogeneous differentiation. Subsequent therapy consisted of standard adjuvant breast cancer chemotherapy and radiation therapy.