[Cytological changes in breast carcinoma in situ].

Certain preinvasive stages precede invasive carcinoma of the breast. Our knowledge about diagnostics, development and prognosis of such preinvasive forms is poor, for it is not possible to observe them directly and continuously. Analysis of the fine needle aspirates of carcinomata in situ of the breast show suspicious apocrine metaplastic cells with nucleoli in 92% and foam cells in 75%, being in contrast to cytological findings on benign lesions. Those peculiarities are more obvious with CLIS than with intraductal CIS lesions. They can be interpreted as particular signs of increased cell proliferation, and, in cases of doubt, should lead to a surgical treatment of suspicious lesions of the breast.