ABSENCE OF NEUROENDOCRINE CELLS IN FETAL AND ADULT MAMMARY-GLANDS - ARE NEUROENDOCRINE BREAST-TUMORS REAL NEUROENDOCRINE TUMORS

Some human breast carcinomas show features of neuroendocrine different iation. The histogenesis of these tumours is debated especially becaus e of the difficulty in locating neuroendocrine cells in normal mammary glands. The aim of this study was to search for neuroendocrine cells in two series of adult and fetal normal mammary glands. Eight female f etus breasts of gestational age between 24 and 37 weeks and 27 cases o f normal adult breast tissues were investigated. Paraffin sections of formalin fixed samples were studied by Grimelins stain and immunohisto chemistry using the monoclonal antibody anti-chromogranin A. An ultras tructural study was performed on a fetal mammary gland at the 37th wee k of gestation. Our results showed no histochemical, immunohistochemic al and ultrastructural evidence of neuroendocrine differentiation in n ormal cells of fetal and adult mammary glands. The absence of neuroend ocrine cells during mammary gland development indicates that the neuro endocrine part of a mammary cancer does not originate from a normal co unterpart but that it is the result of a neuroendocrine differentiatio n during neoplastic progression.