The role of cytology in differentiation of breast lesions.

The introduction of cytologic examination in to the diagnostic procedure has made it possible to define breast lesions better as early as the preoperative stage. However, there are interpretative problems depending on the nature of the lesions that make a histologic examination necessary. The cytology of nipple discharge or FNA of breast lesions would permit the best possible selection of the cases, indicating not only whether surgery is necessary, but also the basis on which it should be performed (outpatient under local anesthesia or inpatient under general anesthesia). The definitive histologic diagnosis of 447 cases submitted to surgery under general anesthesia and of 379 who were operated under local anesthesia has been correlated with the relative cytologic examination. The sensitivity and specificity of the cytologic examination are respectively 97.7% and 98.8%.