Primary Neuroendocrine Carcinoma of the Breast: A Report of Three Cases.

Primary neuroendocrine carcinoma of the breast is extremely rare. More than 97% of neuroendocrine tumors occur in the gastrointestinal and respiratory tracts. Three cases that have been operated in our clinic and had a diagnosis of primary neuroendocrine carcinoma of the breast were assessed, along with literature data. Histopathological diagnoses were obtained by preoperative core needle biopsy. Breast-conserving surgery was performed in two cases, and modified radical mastectomy in one. In all cases, immunohistochemical studies were positive for neuron-specific enolase and synaptophysin. All patients received adjuvant chemotherapy (CT) and one patient received additional radiotherapy (RT). Recurrence or distant metastasis was not detected during long-term follow-up after surgery.