The incidence of ductal carcinoma in situ (DCIS) has steadily increased with widespread screening and advances in breast imaging.
1 Despite its excellent prognosis relative to invasive breast cancer, DCIS remains a heterogeneous disease for which optimal treatment management is commonly debated. The use of whole-breast radiotherapy (WBRT) for DCIS is supported by level 1 data from randomized trials that consistently demonstrate an approximately 50% reduction in relative risk for ipsilateral breast tumor recurrence (IBTR), with very limited in-breast treatment failures with long-term follow-up.
2-5 Because the benefit of WBRT is apparent in all DCIS subgroups, consistently defining subsets in which RT can be omitted remains a challenge.
2-5 More recently, the use of WBRT in patients with higher-risk DCIS has been suggested to be associated with a statistically significant improvement in survival.
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