Abstract: |
Purpose of Review: Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive breast cancer. Despite numerous studies investigating the progression from in situ to invasive disease, there is still controversy as to the mechanisms by which a DCIS comes to become an invasive cancer. Here, we reviewed the state-of-the-art of the pathologic and molecular characterization of DCIS. Recent Findings: DCIS displays intra-lesion genetic heterogeneity. Single-cell sequencing studies have demonstrated that progression from DCIS to invasive breast cancer is a complex phenomenon, which can vary from lesion to lesion. While in some DCIS, multiple clones have the ability to invade, in others, clonal selection likely takes place. Summary: The fact that DCIS displays intra-lesion genetic heterogeneity and that progression varies from patient to patient poses formidable challenges for the development of biomarkers to define the risk of progression to invasive breast cancer. © 2019, Springer Science+Business Media, LLC, part of Springer Nature. |