Premalignant and pre-invasive lesions of the breast

Premalignant and pre-invasive lesions of the breast belong to a complex and heterogeneous group of lesions and represent a matter of remarkable interest from both clinical and biological standpoints. These frequent noninvasive alterations are related with an increased probability of breast cancer development. What is more, these breast abnormalities show extremely variable risks of progression toward invasive forms of disease. Indeed, while there are many histologically defined premalignant lesions in the breast, only a subset of them constitute true neoplastic precursors that will progress to invasive cancer. Disappointingly, it is currently not conceivable to identify a priori, with absolute certainty, which of these precursors will progress and which not. Therefore, classifying risk indicators, precursors, and non-obligate precursors of invasive breast cancer, and ultimately define robust protocols for their clinical management, is a hot topic in the multidisciplinary approach to breast cancer patients, that involves pathologists, radiologists, surgeons, and oncologists.