Current clinical and pathological parameters are important predictors of recurrence in breast ductal carcinoma in situ (DCIS) but they are insufficient to reflect its molecular heterogeneity. Biological characterisation has the potential for individualising therapy for DCIS. Aurora Kinase A (AURKA), located on 20q13.2, shows copy number alteration in DCIS and is a key regulator of cell cycle progression. High expression of AURKA is associated with poor outcome in invasive breast cancer (IBC), however it is not confirmed in the pre-invasive stage. This study aims to assess the role of AURKA in DCIS behaviour.