Department of Radiation Oncology, Seoul National University College of Medicine and Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea.
Cancer Research Institute, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea.
Radiat Oncol. 2021 Nov 18;16(1):222. doi: 10.1186/s13014-021-01948-6.
The purpose of this study was to compare the treatment efficacy and safety of re-irradiation (re-RT) using stereotactic ablative radiotherapy (SABR) and initial SABR for primary, recurrent lung cancer or metastatic lung tumor.
A retrospective review of the medical records of 336 patients who underwent lung SABR was performed. Re-RT was defined as the overlap of the 70% isodose line of second-course SABR with that of the initial radiotherapy, and 20 patients were classified as the re-RT group. The median dose of re-RT using SABR was 54 Gy (range 48-60 Gy), and the median fraction number was 4 (range 4-6). One-to-three case-matched analysis with propensity score matching was used, and 60 patients were included in the initial SABR group of the matched cohort.
The 1- and 2-year local control rates for the re-RT group were 73.9% and 63.3% and those for the initial SABR group in the matched cohort were 92.9% and 87.7%, respectively (P = 0.013). There was no difference in distant metastasis-free, progression-free, and overall survival rates. The crude grade ≥ 2 toxicity rates were 40.0% for the re-RT group and 25.0% for the initial SABR group (P = 0.318). Re-RT group had higher acute grade ≥ 2 toxicity rates (25.0% vs 5.0%, P = 0.031). One incident of grade 3 toxicity (pulmonary) was reported in the re-RT group; there was no grade 4‒5 toxicity.
The local control rate of the in-field re-RT SABR was lower than that of the initial SABR without compromising the survival rates. The toxicity of re-RT using SABR was acceptable.
本研究旨在比较立体定向消融放疗（SABR）再放疗（re-RT）和初始 SABR 治疗原发性、复发性肺癌或转移性肺肿瘤的疗效和安全性。
对 336 例接受肺部 SABR 治疗的患者的病历进行回顾性分析。re-RT 定义为第二疗程 SABR 的 70%等剂量线与初始放疗的重叠，其中 20 例患者被归类为 re-RT 组。再放疗 SABR 的中位剂量为 54Gy（范围 48-60Gy），中位分割次数为 4（范围 4-6）。采用倾向评分匹配的 1:3 病例匹配分析，在匹配队列中纳入 60 例初始 SABR 组患者。
re-RT 组 1 年和 2 年局部控制率分别为 73.9%和 63.3%，匹配队列中初始 SABR 组分别为 92.9%和 87.7%（P=0.013）。无远处转移、无进展和总生存率无差异。急性≥2 级毒性发生率 re-RT 组为 40.0%，初始 SABR 组为 25.0%（P=0.318）。re-RT 组急性≥2 级毒性发生率较高（25.0%比 5.0%，P=0.031）。re-RT 组发生 1 例 3 级毒性（肺部），无 4-5 级毒性。
场内 re-RT SABR 的局部控制率低于初始 SABR，但不影响生存率。SABR 再放疗的毒性是可以接受的。
