Cytological analysis and immunocytochemical expression of Ki67 and Bcl-2 in breast proliferative lesions.

Fine needle aspiration cytology (FNAC) is considered a reliable method for the diagnosis of breast diseases. However, in some cases, cytological diagnosis may be difficult because of the presence of certain cytological parameters, which suggest a proliferative/indeterminate epithelial lesion, ie. a cytological "gray zone" In this retrospective study we considered 37 cases with an uncertain cytological diagnosis and compared the cytological parameters with the histological diagnosis. Furthermore, each case was evaluated with cellular markers such as Ki67 and bcl-2, in order to be able to differentiate the benign from the malignant proliferative breast lumps. Our study showed a correlation between Ki67 expression and malignancy (p<0.001), whereas, no association was observed with decreased or increased bcl-2 activity. Therefore, in our opinion, immunocytochemical Ki67 expression may be helpful in the differentiation of cytologically suspicious/indeterminate breast lesions.