PDF(Pubmed)
Abstract：
OBJECTIVE: Pencil-beam scanning (PBS) is a modern delivery technique used in proton beam therapy (PBT) to reduce normal tissue reactions. No dosimetric correlation between dermatitis and PBS has been reported for breast cancer. The current study aimed to investigate the factors associated with grade 2 or higher dermatitis in patients with breast cancer undergoing PBT using PBS.
METHODS: The medical data of 42 patients with breast cancer who underwent adjuvant radiotherapy between December 2019 and September 2023 were reviewed. All patients received hypofractionated radiotherapy (HFRT), either 26 Gy (relative biological effectiveness [RBE])/five fractions or 40.05 or 43.5 Gy (RBE)/15 fractions, for the whole breast/chest wall with or without nodal irradiation. The duration of acute radiation dermatitis was defined as within 90 days from the start of radiotherapy. The Kaplan-Meier method and Cox proportional hazards model were used for univariate and multivariate analyses of the actuarial rates of grade 2-3 dermatitis.
RESULTS: Twenty-two (52.4%) and 20 (47.6%) patients were diagnosed with grade 1 and 2 dermatitis, respectively. Multivariate analysis revealed a clinical target volume (CTV) ≥ of 320 cc (p = 0.035) and a skin dose of D10cc ≥ 38.3 Gy (RBE) (p = 0.009) as independent factors of grade 2 dermatitis. The 10-week cumulative grade 2 dermatitis rates were 88.2%, 39.4%, and 8.3% (p < 0.001) for patients with both high, either high, and neither high CTV and D10cc, respectively.
CONCLUSIONS: To the best of our knowledge, this is the first study on dosimetric correlations for dermatitis in patients with breast cancer who underwent hypofractionated PBT using PBS. In the era of HFRT, skin dose modulation using PBS may reduce the incidence of dermatitis.
METHODS: The medical data of 42 patients with breast cancer who underwent adjuvant radiotherapy between December 2019 and September 2023 were reviewed. All patients received hypofractionated radiotherapy (HFRT), either 26 Gy (relative biological effectiveness [RBE])/five fractions or 40.05 or 43.5 Gy (RBE)/15 fractions, for the whole breast/chest wall with or without nodal irradiation. The duration of acute radiation dermatitis was defined as within 90 days from the start of radiotherapy. The Kaplan-Meier method and Cox proportional hazards model were used for univariate and multivariate analyses of the actuarial rates of grade 2-3 dermatitis.
RESULTS: Twenty-two (52.4%) and 20 (47.6%) patients were diagnosed with grade 1 and 2 dermatitis, respectively. Multivariate analysis revealed a clinical target volume (CTV) ≥ of 320 cc (p = 0.035) and a skin dose of D10cc ≥ 38.3 Gy (RBE) (p = 0.009) as independent factors of grade 2 dermatitis. The 10-week cumulative grade 2 dermatitis rates were 88.2%, 39.4%, and 8.3% (p < 0.001) for patients with both high, either high, and neither high CTV and D10cc, respectively.
CONCLUSIONS: To the best of our knowledge, this is the first study on dosimetric correlations for dermatitis in patients with breast cancer who underwent hypofractionated PBT using PBS. In the era of HFRT, skin dose modulation using PBS may reduce the incidence of dermatitis.
摘要：
目的：铅笔束扫描（PBS）是质子束治疗（PBT）中用于减少正常组织反应的现代递送技术。对于乳腺癌,没有报道皮炎和PBS之间的剂量学相关性。本研究旨在探讨使用PBS进行PBT的乳腺癌患者与2级或更高级别皮炎相关的因素。
方法：回顾性分析了2019年12月至2023年9月期间接受辅助放疗的42例乳腺癌患者的医学资料。所有患者均接受大分割放疗(HFRT),26Gy（相对生物有效性[RBE]）/5个分数或40.05或43.5Gy（RBE）/15个分数，对于有或没有淋巴结照射的整个乳房/胸壁。急性放射性皮炎的持续时间定义为放疗开始后90天内。使用Kaplan-Meier方法和Cox比例风险模型对2-3级皮炎的精算率进行单变量和多变量分析。
结果：22例（52.4%）和20例（47.6%）患者被诊断为1级和2级皮炎，分别。多因素分析显示，临床目标体积（CTV）≥320cc（p=0.035）和皮肤剂量D10cc≥38.3Gy（RBE）（p=0.009）是2级皮炎的独立因素。10周累计2级皮炎率为88.2%,39.4%,8.3%(p<0.001)的患者，要么高，和高CTV和D10cc，分别。
结论：据我们所知，这是首次使用PBS对接受大分割PBT的乳腺癌患者的皮炎剂量学相关性进行研究.在HFRT时代,使用PBS的皮肤剂量调节可以减少皮炎的发生率。
方法：回顾性分析了2019年12月至2023年9月期间接受辅助放疗的42例乳腺癌患者的医学资料。所有患者均接受大分割放疗(HFRT),26Gy（相对生物有效性[RBE]）/5个分数或40.05或43.5Gy（RBE）/15个分数，对于有或没有淋巴结照射的整个乳房/胸壁。急性放射性皮炎的持续时间定义为放疗开始后90天内。使用Kaplan-Meier方法和Cox比例风险模型对2-3级皮炎的精算率进行单变量和多变量分析。
结果：22例（52.4%）和20例（47.6%）患者被诊断为1级和2级皮炎，分别。多因素分析显示，临床目标体积（CTV）≥320cc（p=0.035）和皮肤剂量D10cc≥38.3Gy（RBE）（p=0.009）是2级皮炎的独立因素。10周累计2级皮炎率为88.2%,39.4%,8.3%(p<0.001)的患者，要么高，和高CTV和D10cc，分别。
结论：据我们所知，这是首次使用PBS对接受大分割PBT的乳腺癌患者的皮炎剂量学相关性进行研究.在HFRT时代,使用PBS的皮肤剂量调节可以减少皮炎的发生率。
