The use offine-needle aspiration biopsy or percutaneous core needle biopsy to diagnose breast lesions has increased during the past few decades. Although the benefits of these procedures are well known, controversies remain about the management of certain categories of breast lesions detected by these methods. This article discusses the management issues in categories of breast lesions, including papillary lesions, atypical lobular hyperplasia and lobular carcinoma in situ, and mucinous lesions diagnosed by the preoperative techniques of aspiration or core biopsy.