Evaluation of the efficacy and the safety of a hypofractionated radiotherapy course with weekly concomitant boost for breast cancer patients treated with conservative breast surgery

doi:10.21608/secioj.2016.5681

Evaluation of the efficacy and the safety of a hypofractionated radiotherapy course with weekly concomitant boost for breast cancer patients treated with conservative breast surgery

Document Type : Original Article

10.21608/secioj.2016.5681

Abstract

Background: Radiation therapy after breast conserving surgery is a standard part of treatment for invasive breast
cancer. Based on radiobiological models, it was found that shorter hypofractiontaed radiation schedules had
equivalent local control to standard radiation therapy. Radiation boost to the tumor bed was evident to be associated
with significant improvement in local control.
Methods: This study included 50 female patients with operable invasive stage I-II breast cancer. Patients
underwent microscopic wide local excision of the primary tumor with axillary lymph node dissection. They
received adjuvant radiotherapy with 42.5 Gy total dose in 16 fractions for whole breast and additional boost dose to
tumor bed of 1Gy once weekly in three consecutive fractions for total boost dose of 3 Gy.
Results: Median age was 47 years: 60% of patients was the most common one. Invasive ductal carcinoma was reported in 94% and hormone receptors were positive in
70% of patients. After median follow-up of 29 months, 2 year DFS was 94%, all patients were alive and ipsilateral
local recurrence was reported in 2% only. Grade III-IV radiation toxicities were not observed. 36% and 12% had
Grade I and II acute skin toxicity respectively. At 12 months, grades (I-II) were reported as (20%-8%)
telangiectasia, (18%-2%) hyperpigmentation, (18%-4%) subcutaneous fibrosis, and (14%-8%) lymphedema
respectively while at 24 months grade II only reported as 2% lymphedema. Acute radiation pneumonitis reported as
8%grade I and 4% grade II while chronic pulmonary fibrosis reported as 6% grade I and 2% grade II. Only 2
patients (7.6%) developed more than 10% drop in the left ventricular ejection fraction (LVEF).
Conclusion: The results of our study suggest there are no increased acute or late toxicities with comparable DFS
and local control rates affiliated with the hypofractionated adjuvant breast radiotherapy schedule with once weekly
concomitant boost as prescribed. Large randomized trials and long-term follow-up are needed to confirm these
favorable findings

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