Primary Neuroendocrine Carcinoma of Breast.

Neuroendocrine differentiation can be identified in a subset of human breast carcinomas, either as scattered cells or as a predominant neuroendocrine component. Clinically, there are no notable or specific differences in presentation from other type of breast tumors. The diagnosis of neuroendocrine breast carcinoma relies mainly on histopathological examination and immunohistochemistry marker study.