BENIGN AND MALIGNANT PAPILLARY LESIONS OF THE BREAST - A CYTOMORPHOLOGIC STUDY

Fine-needle aspiration cytology of benign and malignant papillary lesi ons of the breast has been infrequently described. To define the cytol ogic features of benign and malignant papillary breast lesions better, the authors retrospectively reviewed the fine-needle aspiration cytol ogy of five cases of histologically proven intracystic papillary carci noma (IPC) and six cases of histologically proven papilloma. Clinical information was obtained from the medical records in each case. Intrac ystic papillary carcinoma tended to present as a larger tumor (average , 5 cm) in older women (average, 65.4 years). Papilloma, however, tend ed to present as a smaller tumor (average, 1.5 cm) in younger women (a verage, 43 years). Eighty percent of the IPC cases (4/5) and 50% of th e papilloma cases (3/6) yielded highly cellular aspirates with complex vascular papillae and single columnar cells. Macrophages were a const ant feature of IPC and were present in all but one case of papilloma. Although cellular atypia was not a prominent feature in either IPC or papilloma, moderate atypia was noted in one case of IPC and two cases of papilloma. Severe atypia was noted in a single case of IPC. Althoug h IPC tended to yield a harvest with higher cellularity and single int act cells, no single feature or constellation of findings was consiste ntly reliable in distinguishing IPC from papilloma. The authors found that papillary lesions of the breast demonstrate a distinct cytomorpho logy characterized by complex vascular papillae, columnar cells, and m acrophages. They concluded, however, that, in the absence of overt cyt ologic malignancy, distinguishing between benign and malignant papilla ry breast lesions is difficult, if not impossible.