Ductal Breast Carcinoma In Situ: MammographicFeatures and Its Relation to Prognosis and TumourBiology in a Population Based Cohort

Casting-type calcifications and a histopathological picture with cancer-filled duct-like structures have been presented as breastcancer with neoductgenesis. We correlated mammographic features and histopathological neoductgenesis with prognosis in aDCIS cohort with long follow-up. Mammographic features were classified into seven groups according to Tab ́ar. Histopathologicalneoductgenesis was defined by concentration of ducts, lymphocyte infiltration, and periductal fibrosis. Endpoints were ipsilateral(IBE) in situ and invasive events. Casting-type calcifications and neoductgenesis were both related to high nuclear grade, ER- andPR-negativity, and HER2 overexpression but not to each other. Casting-type calcifications and neoductgenesis were both related toa nonsignificant lower risk of invasive IBE, HR 0.38 (0.13–1.08) and 0.82 (0.29–2.27), respectively, and the HR of an in situ IBE was0.90 (0.41–1.95) and 1.60 (0.75–3.39), respectively. Casting-type calcifications could not be related to a worse prognosis in DCIS.We cannot explain why a more aggressive phenotype of DCIS did not correspond to a worse prognosis. Further studies on how theprogression from in situ to invasive carcinoma is driven are needed.