Al-Hallaq Hania A, Chmura Steven, Salama Joseph K, Winter Kathryn A, Robinson Clifford G, Pisansky Thomas M, Borges Virginia, Lowenstein Jessica R, McNulty Susan, Galvin James M, Followill David S, Timmerman Robert D, White Julia R, Xiao Ying, Matuszak Martha M
Department of Radiation and Cellular Oncology, University of Chicago, Chicago, Illinois.
Department of Radiation and Cellular Oncology, University of Chicago, Chicago, Illinois.
Pract Radiat Oncol. 2016 Nov-Dec;6(6):e291-e298. doi: 10.1016/j.prro.2016.05.004. Epub 2016 May 20.
In 2014, the NRG Oncology Group initiated the first National Cancer Institute-sponsored, phase 1 clinical trial of stereotactic body radiation therapy (SBRT) for the treatment of multiple metastases in multiple organ sites (BR001; NCT02206334). The primary endpoint is to test the safety of SBRT for the treatment of 2 to 4 multiple lesions in several anatomic sites in a multi-institutional setting. Because of the technical challenges inherent to treating multiple lesions as their spatial separation decreases, we present the technical requirements for NRG-BR001 and the rationale for their selection.
Patients with controlled primary tumors of breast, non-small cell lung, or prostate are eligible if they have 2 to 4 metastases distributed among 7 extracranial anatomic locations throughout the body. Prescription and organ-at-risk doses were determined by expert consensus. Credentialing requirements include (1) irradiation of the Imaging and Radiation Oncology Core phantom with SBRT, (2) submitting image guided radiation therapy case studies, and (3) planning the benchmark. Guidelines for navigating challenging planning cases including assessing composite dose are discussed.
Dosimetric planning to multiple lesions receiving differing doses (45-50 Gy) and fractionation (3-5) while irradiating the same organs at risk is discussed, particularly for metastases in close proximity (≤5 cm). The benchmark case was selected to demonstrate the planning tradeoffs required to satisfy protocol requirements for 2 nearby lesions. Examples of passing benchmark plans exhibited a large variability in plan conformity.
NRG-BR001 was developed using expert consensus on multiple issues from the dose fractionation regimen to the minimum image guided radiation therapy guidelines. Credentialing was tied to the task rather than the anatomic site to reduce its burden. Every effort was made to include a variety of delivery methods to reflect current SBRT technology. Although some simplifications were adopted, the successful completion of this trial will inform future designs of both national and institutional trials and would allow immediate clinical adoption of SBRT trials for oligometastases.
2014年，NRG肿瘤学小组发起了首个由美国国立癌症研究所资助的1期立体定向体部放射治疗（SBRT）临床试验，用于治疗多器官部位的多发转移瘤（BR001；NCT02206334）。主要终点是在多机构环境中测试SBRT治疗多个解剖部位2至4个多发病变的安全性。由于随着多个病变空间距离减小，治疗存在固有的技术挑战，我们介绍了NRG-BR001的技术要求及其选择依据。
患有乳腺癌、非小细胞肺癌或前列腺癌且原发肿瘤得到控制的患者，如果其全身7个颅外解剖部位存在2至4个转移瘤，则符合入选条件。处方剂量和危及器官剂量由专家共识确定。资质要求包括：（1）使用SBRT对影像与放射肿瘤学核心体模进行照射；（2）提交图像引导放射治疗病例研究；（3）规划基准病例。讨论了处理具有挑战性的计划病例的指南，包括评估复合剂量。
讨论了在对相同危及器官进行照射时，对接受不同剂量（45 - 50 Gy）和分割次数（3 - 5次）的多个病变进行剂量规划的问题，特别是对于相邻（≤5 cm）转移瘤。选择基准病例以展示满足两个相邻病变方案要求所需的计划权衡。通过基准计划的示例显示计划适形性存在很大差异。
NRG-BR001是基于从剂量分割方案到最小图像引导放射治疗指南等多个问题的专家共识而制定的。资质认定与任务相关而非解剖部位，以减轻负担。尽一切努力纳入各种递送方法以反映当前的SBRT技术。尽管采用了一些简化措施，但该试验的成功完成将为未来国家和机构试验的设计提供参考，并将使SBRT治疗寡转移瘤的试验能够立即应用于临床。
