Neuroendocrine carcinoma of the breast is a rare neoplasm that accounts for only about 2% to 5% of all mammary cancers. This tumor variant usually occurs in elderly women who are in their sixth or seventh decade of life. The prognostic significance of neuroendocrine differentiation is still unclear. The histological grade seems to be the most important parameter with respect to prognosis. We report a 69-years-old woman with invasive neuroendocrine carcinoma of the right breast. Immunostaining to detect synaptophycin and chromogranin played an integral role in making the correct diagnosis.