That study showed that the Oncotype DCIS recurrence score was significantly associated with the risk of ipsilateral breast recurrence in ER+ patients [hazard ratio (HR), 2.3; 95% CI, 1.41-3.59; p<0.001] and in the full cohort (including both ER positive and negative patients, 95% of whom were ER+) (HR=2.2; 95% CI, 1.43-3.22; p<0.001). Here, ESR1 is linked to ductal breast carcinoma in situ.