[Lobular carcinoma of the breast with neuroendocrine differentiation. Study of a case]

A breast tumor with morphologic features of neuroendocrine differentiation and containing large amounts of estrogen receptor protein was associated with areas of typical infiltrating lobular carcinoma. The neuroendocrine areas were argyrophilic, NSE positive and ultrastructurally did not show dense granules. Results of flow cytometric analysis revealed aneuploid nuclear DNA.