Recent advances in the diagnosis and management of B3 lesions

Lesions of uncertain malignant potential (B3 lesions) comprise a number of diagnostic entities; some of which are associated with atypia. These lesions can be challenging diagnostically and management wise. Traditionally, diagnostic surgical excision was performed for those lesions. More recently, vacuum assisted excision has been adopted for adequate sampling of those lesions. The last couple of years has witnessed advances in the understanding of the biology and outcome of B3 lesions with relevant guidelines produced to guide the multidisciplinary teams managing patients with B3 diagnoses. This review covers the histological and radiological features of B3 lesions, updates on the current evidence and new management guidelines and provides practical tips for pathologists involved in the diagnosis and multidisciplinary team discussion of those difficult lesions.