MAMMARY EPIDERMOID INCLUSION CYSTS AFTER WIDE-CORE NEEDLE BIOPSIES

Aims: To investigate the prevalence of squamous epidermoid inclusion c ysts after wide-core needle biopsy, Methods and results: Epidermoid in clusion cysts were found in five of 17 surgical excisions (29%) after preliminary wide-core needle biopsies in a 7-month period. Thereafter they were not seen in 26 subsequent postwide-core surgical excisions i n a period of 6 months, Conclusions: The cysts appear to be an iatroge nic complication of wide-core biopsy and need morphological recognitio n in order to avoid confusion with spontaneous squamous metaplasia of benign or malignant breast epithelium. Longer term implications are un known.