Is excision alone adequate for low-risk DCIS of the breast treated with breast conserving therapy Reevaluating the role of adjuvant radiation therapy

摘要

Background Ductal carcinoma in situ (DCIS) represents a quarter of newly diagnosed breast neoplasms, with the majority of cases detected on routine screening mammography in asymptomatic women. Currently, most women with newly diagnosed DCIS are eligible for breast conserving therapy (BCT); however, significant controversy exists regarding whether or not to add radiation treatment (RT) after surgical excision in low-risk patients. Results While four older prospective randomized clinical trials have shown that the addition of RT after lumpectomy reduces the risk of ipsilateral breast tumor recurrence (IBTR) by approximately 50 %, recent studies have continued to attempt to identify a subset of patients with favorable risk DCIS who are at a sufficiently low-risk of IBTR that omitting RT might be reasonable. While a number of smaller studies have shown promising results, recent prospective data have consistently affirmed the increased risk of IBTR with the omission of RT, with no subset of patients consistently identified that can be safely observed without RT. While radiation after lumpectomy remains the "standard of care," even in these low-risk patients, future directions include improvements in genetic assays to better identify low-risk patients and new RT techniques and schedules that can potentially reduce the duration of therapy and toxicity while improving quality of life for patients.Conclusion Based on the data available, we continue to recommend radiation therapy for low-risk patients with DCIS as no discernible subset has been identified that does not benefit from radiation therapy.