Ductal carcinoma in situ (DCIS) breast cancer treated with 3-week accelerated hypofractionated whole-breast radiation therapy and concomitant boost

Abstract

Introduction: In patients with ductal carcinoma in situ (DCIS), the clinical outcomes with hypofractionated (HF) whole-breast radiation (WBRT), as well as the role of lumpectomy boost, continue to be evaluated. In this paper, we report our experience on DCIS patients treated with HF WBRT with concomitant boost (CB). Method(s): Early-stage (DCIS, stages I and II) breast cancer patients were treated on an IRB-approved prospective single-arm study with HF WBRT and CB. This study includes only the DCIS subset of patients prescribed a dose of 40.5 Gy x 2.7 Gy per fraction to WB with CB of 4.5 Gy x 0.3G y per fraction over 15 fractions. A total of 107 breasts in 104 patients met the study criteria. Result(s): All patients underwent lumpectomy with negative margins. Median age was 59 years. DCIS nuclear grade distribution was 9.3% grade 1, 50.5% grade 2, and 37.4% grade 3. Majority (86%) were ER positive. 41.1% received endocrine therapy. With median follow-up of 74 months (range, 12-158), 5-year actuarial overall survival was 97.2%. At the time of this report, no patient has experienced local relapse. The CTCAE grades 1 and 2 acute skin toxicity was 66.4% and 3.7%, respectively. No patients experienced grade 3 or higher skin toxicity, breast pain, and fatigue. Conclusion(s): The HF schedule with CB in DCIS patients is well tolerated and associated with excellent clinical outcomes. This schedule affords the benefit of delivering higher dose to the lumpectomy site without protracting overall treatment time.Copyright © 2019, The Author(s).