Abstract
Apocrine carcinoma of the breast is occurring with increased frequency in Japan. We report a 72-year-old woman who was admitted for a painless tumor in the left breast. An excisional biopsy was performed, and histological examination of the tumor specimen revealed as breast apocrine carcinoma. In the imprint specimen, cell clusters with slight overlapping or flattened sheets and individually scattered atypical cells around the clusters were observed. Atypical cells showed striking pleomorphism and large nuclei with increased chromatin and one or two distinct nucleoli. The cytoplasm was abundant and had very fine eosinophilic granules. Multivacuolated (globoid) cells were mixed. Immunohistochemical staining for and-gross cystic disease fluid protein 15 (GCDFP-15), carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), macrophages, αl-antitrypsin, α1-antichymotrypsin and lysozyme was performed. Tumor cells showed distinct differentiation of apocrine epithelium because of mosaic positive staining for anti-GCDFP-15. Multivacuolated cells showed positive staining for anti-GCDFP-15, CEA and EMA and negative staining for anti-macrophage and lysozyme. Therefore, the results of immunohistochemical staining suggested that multivacuolated cells did not originate from the macrophages, but from the epithelium.
