Department of Radiation Oncology, Institut Curie, Paris, France.
University of Versailles St Quentin, Paris, France.
Acta Oncol. 2023 Dec;62(12):1791-1797. doi: 10.1080/0284186X.2023.2267170. Epub 2023 Nov 25.
Ultra-hypofractionation breast radiotherapy is a safe alternative to moderate hypofractionation. This study reports the results of two ultrahypofractionated regimens used in clinical practice in a high-volume radiotherapy center in terms of efficacy and of tolerance.
we included all patients treated in an adjuvant setting with five fractions after breast conserving surgery (BCS), for a histologically-confirmed invasive or breast carcinoma. Radiotherapy regimens after BCS were either a 5-week schedule with 5 weekly fractions of 5,7 Gy or a one-week schedule with 5 daily fractions of 5,2 Gy. Adverse events were recorded and local-relapse free survival (LRFS), locoregional-relapse free survival (LRRFS), metastasis-free survival (MFS), for breast-cancer specific survival (BCSS) and overall survival (OS) were evaluated.
Between December 2014 and December 2022, 396 patients (400 breasts) were treated with ultrahypofractionated radiotherapy. Five-year LRFS was 98.8% (95% confidence interval: 97.1%-100%), and 5-year OS was 96.0% (95%CI: 92.6-99.5%). Age was statistically associated with OS in univariate analysis (HR: 1.16, 95%CI: 1.04-1.42, = .01). Four patients (1.0%) experienced acute grade 3 radiation-induced adverse events, and 8 patients (2.3%) acute grade 2 toxicities. Twenty-three patients (5.8%) experienced late toxicity, all of them being graded as grade 1. The use of the 5.7 Gy-weekly-fraction regimen and the delivery of a tumor bed boost were significantly associated with acute radiodermatitis ( < .01; = .02; respectively) and late fibrosis ( < .01; = .049; respectively).
ultrahypofractionated radiotherapy was associated with an excellent tumor control rate in our 'real-life' cohort with low-risk breast cancer patients. However, delivery of a tumor bed boost and using weekly 5.7-Gy fractions were associated with an increased risk of acute and late cutaneous toxicities.
超分割乳房放疗是一种替代中度分割的安全选择。本研究报告了在一个大容量放射治疗中心，两种超分割方案在疗效和耐受性方面的临床实践结果。
我们纳入了所有接受保乳手术后（BCS）辅助治疗的患者，这些患者均接受了五个疗程的治疗，病理确诊为浸润性或乳腺浸润性癌。BCS 后的放疗方案为 5 周方案，每周 5 次，每次 5.7Gy，或 1 周方案，每日 5 次，每次 5.2Gy。记录不良反应，评估局部无复发生存率（LRFS）、局部区域无复发生存率（LRRFS）、无远处转移生存率（MFS）、乳腺癌特异性生存率（BCSS）和总生存率（OS）。
2014 年 12 月至 2022 年 12 月，396 例（400 例乳房）患者接受了超分割放疗。5 年 LRFS 为 98.8%（95%可信区间：97.1%-100%），5 年 OS 为 96.0%（95%CI：92.6-99.5%）。单因素分析显示，年龄与 OS 统计学相关（HR：1.16，95%CI：1.04-1.42， = .01）。4 例（1.0%）患者发生急性 3 级放射性不良事件，8 例（2.3%）患者发生急性 2 级毒性。23 例（5.8%）患者发生晚期毒性，均为 1 级。每周 5.7Gy 分次方案的应用和肿瘤床加量与急性放射性皮炎（ < .01； = .02；分别）和晚期纤维化（ < .01； = .049；分别）显著相关。
在我们的低危乳腺癌患者的“真实生活”队列中，超分割放疗与优异的肿瘤控制率相关。然而，肿瘤床加量和每周 5.7Gy 分次方案的应用与急性和晚期皮肤毒性风险增加相关。
