[Mucinous breast carcinomas with neuroendocrine differentiation]

Mucinous breast carcinomas, denominated also gelatinous, mucoid and colloid (collomas), represent a heterogeneous group of neoplasms. More than half of them exhibit signs of neuroendocrine differentiation. Eighteen mucus producing carcinomas of the breast are subjected to morphological study. On the ground of demonstrating argyrophilia by the methods of Grimelius and Churukian--Shenk, and presence of secreting granules during electron microscopic study, they are assigned under the heading apudomas, i.e. tumors of the diffuse endocrine system, or the so-called APUD-system. The important practical implications of demonstrating neuroendocrine cells with a special reference to the biological patterns of this particular type of tumors are discussed.