Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Japan.
Department of Radiation Oncology, Japanese Red Cross Wakayama Medical Center, Wakayama, Japan.
Radiother Oncol. 2022 Jul;172:18-22. doi: 10.1016/j.radonc.2022.04.028. Epub 2022 May 2.
This study aimed to evaluate the safety and efficacy of dynamic tumor tracking-stereotactic body radiotherapy (DTT-SBRT) for lung tumors.
Patients with cStage I primary lung cancer or metastatic lung cancer with an expected range of respiratory motion of ≥10 mm were eligible for the study. The prescribed dose was 50 Gy in four fractions. A gimbal-mounted linac was used for DTT-SBRT delivery. The primary endpoint was local control at 2 years.
Forty-eight patients from four institutions were enrolled in this study. Forty-two patients had primary non-small-cell lung cancer, and six had metastatic lung tumors. DTT-SBRT was delivered for 47 lesions in 47 patients with a median treatment time of 28 min per fraction. The median respiratory motion during the treatment was 13.7 mm (range: 4.5-28.1 mm). The motion-encompassing method was applied for the one remaining patient due to the poor correlation between the abdominal wall and tumor movement. The median follow-up period was 32.3 months, and the local control at 2 years was 95.2% (lower limit of the one-sided 85% confidence interval [CI]: 90.3%). The overall survival and progression-free survival at 2 years were 79.2% (95% CI: 64.7%-88.2%) and 75.0% (95% CI: 60.2%-85.0%), respectively. Grade 3 toxicity was observed in one patient (2.1%) with radiation pneumonitis. Grade 4 or 5 toxicity was not observed.
DTT-SBRT achieved excellent local control with low incidences of severe toxicities in lung tumors with respiratory motion.
本研究旨在评估动态肿瘤跟踪立体定向体放射治疗（DTT-SBRT）治疗肺部肿瘤的安全性和有效性。
本研究纳入了预期呼吸运动范围≥10mm的 cStage I 期原发性肺癌或转移性肺癌患者。处方剂量为 50Gy，分 4 次给予。采用带有万向节的直线加速器进行 DTT-SBRT 治疗。主要终点为 2 年局部控制率。
本研究共纳入了来自 4 家机构的 48 例患者。42 例患者患有原发性非小细胞肺癌，6 例患者患有转移性肺癌。47 例患者的 47 个病灶接受了 DTT-SBRT 治疗，每个病灶的治疗时间中位数为 28 分钟。治疗过程中，呼吸运动的中位数为 13.7mm（范围：4.5-28.1mm）。由于腹壁与肿瘤运动之间相关性较差，1 例患者采用了包绕运动范围的方法。中位随访时间为 32.3 个月，2 年局部控制率为 95.2%（单侧 85%置信区间下限：90.3%）。2 年总生存率和无进展生存率分别为 79.2%（95%CI：64.7%-88.2%）和 75.0%（95%CI：60.2%-85.0%）。1 例患者（2.1%）出现 3 级放射性肺炎。未观察到 4 级或 5 级毒性。
DTT-SBRT 治疗肺部肿瘤具有出色的局部控制效果，且在呼吸运动的情况下，严重毒性反应发生率较低。
