Liquid-Based Cytology and Cell Block in Breast Lesions

Liquid-based cytology (LBC) is a method of retrieving and processing cytologic material for assessment. First developed for cervical cytology screening in an effort to reduce inadequacy rates, the use of LBC has extended to FNAC as well. In LBC, cytologic material is placed in a fixative solution and, depending on the system, is then centrifuged or filtered to produce monolayers of cells on glass slides and this can enhance and facilitate interpretation. These monolayered preparations can also be subjected to adjunctive studies like immunohistochemistry. There are many ways of achieving monolayered cell preparations, which may be through automated platforms like ThinPrep and SurePath, or via alternative manual techniques that are less costly and that can produce similar monolayered preparations. Overall, the literature reports overlapping sensitivities and specificities between conventional smears and liquid-based cytology slides in the context of breast FNAC. Notably, however, one study found that monolayered preparations of breast aspirates gave definitive diagnoses significantly more often than aspirates subjected to conventional smear preparations (72.8% vs. 58.5%) and that this benefit was most frequently observed in malignant breast lesions.