Nomoto Yoshihito, Ii Noriko, Murashima Shuichi, Yamashita Yasufumi, Ochiai Satoru, Takada Akinori, Toyomasu Yutaka, Kawamura Tomoko, Sakuma Hajime
Department of Radiation Oncology, Graduate School of Medicine, Mie University, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.
Department of Radiation Oncology, Mie University Hospital, 2-174 Edobashi, Tsu, Mie 514-8507, Japan.
J Radiat Res. 2017 Nov 1;58(6):849-853. doi: 10.1093/jrr/rrx031.
Endobronchial brachytherapy (EBB) is an effective treatment for endobronchial tumors. However, bronchial toxicity caused by over-irradiation remains problematic. To decrease bronchial toxicity, we developed a source-centralizing applicator for EBB. The purpose of the present study was to assess the efficacy and safety of EBB with varying reference dose points according to the bronchial diameter, using a source-centralizing applicator. We reviewed 15 patients with endobronchial carcinoma who were treated with curative intent using a combination of external beam radiotherapy (EBRT) and high-dose-rate EBB between 2005 and 2014. During each EBB session, we used a source-centralizing applicator that maintained the source-delivering catheter in the center of the bronchial lumen. Reference dose points were 5-7 mm from the source axis, depending on the bronchial diameter. The median radiation doses of EBRT and EBB were 40 Gy in 20 fractions and 18 Gy in 3 fractions, respectively. The median observation period was 36 months. The 3-year overall survival, progression-free survival and local control rates were 79%, 77% and 100%, respectively. Grade 2 radiation pneumonitis was observed in two cases. Bronchial toxicities, such as hemoptysis or the symptoms of chronic bronchitis, were not observed. EBB with varying reference dose points according to bronchial diameter, using a source-centralizing applicator, is a promising procedure that may be effective for tumor elimination and reducing toxicity to the bronchial wall.
支气管内近距离放射疗法（EBB）是治疗支气管内肿瘤的一种有效方法。然而，过度照射引起的支气管毒性仍然是个问题。为了降低支气管毒性，我们开发了一种用于EBB的源集中式施源器。本研究的目的是使用源集中式施源器，评估根据支气管直径设置不同参考剂量点的EBB的疗效和安全性。我们回顾了2005年至2014年间15例接受根治性治疗的支气管内癌患者，这些患者接受了外照射放疗（EBRT）和高剂量率EBB联合治疗。在每次EBB治疗期间，我们使用了一种源集中式施源器，该施源器将源输送导管保持在支气管腔的中心。根据支气管直径，参考剂量点距离源轴5 - 7毫米。EBRT和EBB的中位放射剂量分别为20次分割共40 Gy和3次分割共18 Gy。中位观察期为36个月。3年总生存率、无进展生存率和局部控制率分别为79%、77%和100%。2例患者出现2级放射性肺炎。未观察到咯血或慢性支气管炎症状等支气管毒性。使用源集中式施源器，根据支气管直径设置不同参考剂量点的EBB是一种有前景的方法，可能对消除肿瘤和降低对支气管壁的毒性有效。
