ABSTRACT
Lobular neoplasia was first described as a pathological entity by Ewing in 1919,1 although it was a long time before much was known about the biology of the condition. This chapter provides an overview of the current definition, subtypes, diagnosis, and modern management of lobular neoplasia of the breast. Florid LCIS describes distended breast ducts by non-high-grade lobular cell nuclei. Lobular neoplasia is most frequently diagnosed in women aged between 40 and 50 years. Classical lobular neoplasia is regarded as a marker for an increased risk of subsequent malignancy, rather than a precursor. Since 2016, the UK NHS Breast Screening Clinical Guidelines recommended VAE of ‘B3 lesions showing classical lobular neoplasia. The American Society of Breast Surgeons advises no treatment following a core biopsy diagnosis, provided the imaging is concordant and no other lesions are present in the biopsy.
