Usefulness of supplementary ultrasound surveillance in the detection of a second breast cancer in patients with ductal carcinoma in situ.

Introduction: Supplementary ultrasound surveillance in breast cancer patients can detect additional cancers but is associated with unnecessary biopsies and follow-ups. We aim to determine, in patients with ductal carcinoma in situ (DCIS), the prevalence and factors associated with second breast cancers and the usefulness of supplementary ultrasound surveillance. This is the first study which focused on the usefulness of ultrasound surveillance in DCIS patients.