Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada; Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario, Canada.
Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada; Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario, Canada.
Clin Lung Cancer. 2018 Jul;19(4):e529-e532. doi: 10.1016/j.cllc.2018.04.001. Epub 2018 Apr 18.
Lung stereotactic body radiotherapy (SBRT) is considered a standard curative treatment for medically inoperable early stage non-small-cell lung cancer (NSCLC). Patients with ultracentral tumors (signifying tumors whose planning target volume touches or overlaps the central bronchial tree, esophagus, or pulmonary artery) may be at higher risk of serious toxicities such as bronchial stricture and collapse, esophageal strictures, tracheal-esophageal fistula, and hemorrhage. The primary objective of the study is to determine the maximum tolerated dose of radiotherapy for ultracentral NSCLC.
This multicenter phase 1 dose-escalation study will use a time-to-event continual reassessment method (TITE-CRM). Accrual will start at level 1 (60 Gy in 8 fractions delivered daily). The model will use all available information from previously accrued patients to assign the highest dose with a predicted risk of grade 3-5 toxicity of 30% or less. All patients with newly diagnosed stage T1-3 N0M0 NSCLC (International Union Against Cancer, 8th edition) with tumor size ≤ 6 cm and meeting the criteria for ultracentral location (ie, tumors whose planning target volume touches or overlaps the central bronchial tree, esophagus, pulmonary vein, or pulmonary artery) will be eligible for this study.
It is important to identify a safe dose-fractionation regimen for treating ultracentral tumors with SBRT. In addition, the data from this study may be informative in guiding future studies on the use of SBRT in treating malignancies within the mediastinum-for example, for salvage treatment of mediastinal lymph nodes for recurrent NSCLC or mediastinal oligometastases.
立体定向体部放疗（SBRT）被认为是无法手术的早期非小细胞肺癌（NSCLC）的标准治疗方法。超中央肿瘤（表示肿瘤的计划靶区接触或重叠中央支气管树、食管或肺动脉）的患者可能有更高的严重毒性风险，如支气管狭窄和塌陷、食管狭窄、气管食管瘘和出血。该研究的主要目的是确定超中央 NSCLC 的最大耐受放疗剂量。
这项多中心 1 期剂量递增研究将使用时间事件连续再评估方法（TITE-CRM）。入组将从第 1 级（60Gy，每天 8 次）开始。该模型将利用以前入组患者的所有可用信息，预测毒性等级为 3-5 的风险为 30%或更低的最高剂量。所有新诊断为 T1-3N0M0 NSCLC（国际抗癌联盟，第 8 版）的患者，肿瘤大小≤6cm，且符合超中央位置标准（即肿瘤的计划靶区接触或重叠中央支气管树、食管、肺静脉或肺动脉），均符合本研究的条件。
确定 SBRT 治疗超中央肿瘤的安全剂量分割方案非常重要。此外，这项研究的数据可能有助于指导未来 SBRT 治疗纵隔恶性肿瘤的研究，例如复发性 NSCLC 或纵隔寡转移的纵隔淋巴结挽救治疗。
