Epithelial displacement in surgical breast specimens following needling procedures.

Lesional breast tissue is often subjected to various needling procedures prior to resection and formal histologic examination. In this article, we describe a series of 29 surgical breast specimens in which histologic examination revealed fragments of benign or malignant epithelium displaced in breast stroma or in lymphovascular channels, associated with the traumatic effects of a needling procedure. Follow-up revealed that a variety of different interventions, including needle localization, fine-needle aspiration, infiltration with local anesthetic, core biopsy, and suture placement, preceded the surgical resection in these instances. The displaced epithelial fragments mimic stromal invasion to a variable degree and may represent a potential source of misdiagnosis. The incidence and biological significance of epithelial displacement in this context are as yet unknown.