Hypofractionation with simultaneous boost in breast cancer patients receiving adjuvant chemotherapy: A prospective evaluation of a case series and review of the literature

Introduction: To evaluate acute toxicity and cosmetic outcomes of hypofractionated simultaneous integrated boost (SIB) as adjuvant treatment after breast-conserving surgery and adjuvant chemotherapy and to review the association of chemotherapy and short fractionation with boost. Materials and methods: Patients presenting early-stage breast cancer were enrolled in a phase II trial. All patients received VMAT-SIB technique to the whole breast and tumor bed in 15 fractions, for a total dose of 40.5 and 48 Gy. Acute and late skin toxicities and breast pain were recorded. Cosmetic outcomes were also assessed as excellent/good or fair/poor. Results: Between August 2010 and December 2015, 787 consecutive patients were treated and had at least 2 year follow-up. A subset of 175 patients underwent adjuvant chemotherapy (median age of 55 years) and was analysed. The median follow up was 39 months (range 24-80). At the end of RT treatment, skin toxicity was G1 in 51.1% of patients, G2 in 9.7%. At 2 years of follow up, it was G1 in 13.5% of patients, no cases >= G2; cosmetic outcome was excellent in 63.5% and good in 36.5% of the patients. No significant difference compared to the patients without systemic therapy was observed. Conclusion: Hypofractionated VMAT-SIB in patients who had undergone adjuvant systemic therapy was safe and well tolerated in terms of acute and early late settings and cosmesis. Our data confirmed the results of other studies published on the association of hypofractionation and chemotherapy or concomitant boost. (C) 2018 Elsevier Ltd. All rights reserved.