Ben Amor Raouia, Bohli Meriem, Naimi Zeineb, Aissaoui Dorra, Mejri Nesrine, Yahyaoui Jamel, Hamdoun Awatef, Kochbati Lotfi
Faculty of Medicine, University of Tunis El Manar, 1007, Tunis, Tunisia.
Department of Radiation Oncology, Abderrahmen Mami Hospital, 2080, Ariana, Tunisia.
Strahlenther Onkol. 2023 Jan;199(1):48-54. doi: 10.1007/s00066-022-01985-4. Epub 2022 Aug 9.
The purpose of this study was to evaluate acute skin toxicity in early breast cancer patients treated with hypofractionated radiotherapy (HFRT) after breast-conserving surgery and to identify factors predictive for grade ≥ 2 acute skin toxicity.
A monocentric retrospective study was carried out using cases treated between December 2017 and November 2020. We analyzed data from 202 patients with early breast cancer treated with 3D hypofractionated RT (40.05 Gy in 15 fractions) to the whole breast with or without regional lymph nodes, followed by 13.35 Gy in 5 fractions to the tumor bed. Acute skin toxicity was monitored during RT according to CTCAE (common toxicity criteria for adverse events) scale. Univariate and multivariate analyses were performed to assess predictive factors of acute skin toxicity.
Overall, there was no erythema in 9%, grade 1 erythema in 64.5%, grade 2 in 24%, and grade 3 in 2.5%. No grade 4 erythema was seen. Median delay between RT initiating and maximum skin reaction was 22 days (range 4-44 days). No patient interrupted treatment. In univariate analysis, the rate of acute skin toxicity grade 2---3 (G2-3) was significantly higher for patients with larger tumor size (p = 0.02), body mass index > 27 (p = 0.04), and time between chemotherapy (CT) and RT less than 20 days (p = 0.01). Dosimetric risk factors for acute skin toxicity G2‑3 were breast volume > 800 cc (p = 0.000), boost volume > 18 cc (p = 0.002), V105% > 40 cc (p = 0.03), and Dmax > 56 Gy (p = 0.007). CT, trastuzumab, regional lymph node radiation, and age were not correlated with increased skin toxicity. In multivariate analysis, acute skin toxicity correlated with T stage (p = 0.032), breast volume > 800 cc (p = 0.012), boost volume > 18 cc (p = 0.04), and Dmax > 56 Gy (p = 0.035).
Our results confirm that whole breast with or without lymph nodes hypofractionated RT is safe and well tolerated. The factors strongly associated with a decreased risk of G2‑3 skin toxicity are T1, breast volume < 800 c, boost volume < 18 cc, and Dmax < 56 Gy. Long-term follow-up is needed to evaluate late toxicity.
本研究旨在评估保乳手术后接受大分割放疗（HFRT）的早期乳腺癌患者的急性皮肤毒性，并确定预测≥2级急性皮肤毒性的因素。
进行了一项单中心回顾性研究，使用2017年12月至2020年11月期间治疗的病例。我们分析了202例早期乳腺癌患者的数据，这些患者接受了全乳三维大分割放疗（15次分割，共40.05 Gy），照射范围包括或不包括区域淋巴结，随后对瘤床进行5次分割，共13.35 Gy。放疗期间根据不良事件通用毒性标准（CTCAE）量表监测急性皮肤毒性。进行单因素和多因素分析以评估急性皮肤毒性的预测因素。
总体而言，9%的患者无红斑，64.5%的患者为1级红斑，24%的患者为2级红斑，2.5%的患者为3级红斑。未见4级红斑。放疗开始至皮肤最大反应的中位延迟时间为22天（范围4 - 44天）。无患者中断治疗。在单因素分析中，肿瘤体积较大（p = 0.02）、体重指数>27（p = 0.04）以及化疗（CT）与放疗之间的时间间隔小于20天（p = 0.01）的患者，2 - 3级（G2 - 3）急性皮肤毒性发生率显著更高。急性皮肤毒性G2 - 3的剂量学危险因素包括乳房体积>800 cc（p = 0.000）、瘤床增量体积>18 cc（p = 0.002）、V105%>40 cc（p = 0.03）以及Dmax>56 Gy（p = 0.007）。CT、曲妥珠单抗、区域淋巴结放疗和年龄与皮肤毒性增加无关。在多因素分析中，急性皮肤毒性与T分期（p = 0.032）、乳房体积>800 cc（p = 0.012）、瘤床增量体积>18 cc（p = 0.04）以及Dmax>56 Gy（p = 0.035）相关。
我们的结果证实，全乳无论是否包括淋巴结的大分割放疗是安全且耐受性良好的。与G2 - 3皮肤毒性风险降低密切相关的因素是T1期、乳房体积<800 c、瘤床增量体积<18 cc以及Dmax<56 Gy。需要进行长期随访以评估晚期毒性。
