Aspiration cytology of apocrine carcinoma of the breast

In order to elucidate the cytologic characteristics of apocrine carcinoma of the breast, cytologic specimens obtained by needle aspiration were analyzed in 9 histologically confirmed apocrine carcinomas. For comparison, 15 benign lesions with apocrine metaplasia were also studied. Cytologic features of cancer cells from apocrine carcinoma were as follows: 1. Carcinoma cells showed abundant fine granular, eosinophilic cytoplasm similar to that seen in benign metaplastic cells. 2. A tendency for the cancer cells to overlap or to break loose from the cluster was apparent. 3. Cytoplasmic vacuolization was found in some cancer cells, and cell borders were often indistinct. 4. Cancer cells showed more cellular and nuclear atypism with prominent nucleoli than did benign metaplastic cells.