Ductal Carcinoma In Situ: Review of the Role of Radiation Therapy and Current Controversies

Despite a lack of randomized trials comparing breast-conserving therapy (BCT) and mastectomy, BCT represents a standard of care in the management of ductal carcinoma in situ (DCIS). Traditionally, BCT has consisted of breast-conserving surgery (BCS) followed by adjuvant radiotherapy (RT), with multiple randomized trials demonstrating an approximately 50% reduction in rates of local recurrence with adjuvant RT. However, over the past 2 decades, several trials have been performed to identify a low-risk cohort of patients for whom BCS alone would provide an acceptably low risk of local recurrence. Currently, patients who can forgo adjuvant RT without significantly increasing their chance of local recurrence have not been consistently identified. While future studies will look at tumor genetics to help identify low-risk cohorts, modern RT also allows for shortened courses of treatment to reduce the duration of adjuvant RT.