Clayton Ravinder, Liu Hong-Wei, Khan Rao, Udowicz Mona, Bayliss Yvette, Krobutschek Krista, Herring Colleen, Lau Harold
Department of Radiation Oncology, University of Calgary, Calgary, AB, Canada.
Department of Radiation Oncology, University of Calgary, Calgary, AB, Canada.
J Med Imaging Radiat Sci. 2012 Dec;43(4):245-252. doi: 10.1016/j.jmir.2012.05.003. Epub 2012 Jul 19.
For patients with inoperable Stage I (T1-T2, N0, M0) non-small-cell lung cancer, stereotactic ablative radiotherapy (SABR), also known as stereotactic body radiation therapy (SBRT), has demonstrated survival outcomes similar to surgery. Lung SABR is a technically challenging means of delivering precise, high-dose radiation to a small tumor volume. At many cancer centres, the widespread use of SABR is impeded by the complexity of the implementation process. This study will aim to provide a detailed guide to the steps involved in delivering lung SABR in a reliable and efficient manner.
The execution of this intricate treatment program at our cancer centre required the collaboration of a multidisciplinary team. Input from several professionals within radiation oncology was necessary, including medical physicists, dosimetrists, radiation therapists, nurses, and radiation oncologists. Expert guidelines have been developed which give careful consideration to each step of the process, including 1) reliable and reproducible patient immobilization, 2) a method to account for tumor and organ motion, 3) the use of multiple treatment fields to deliver highly conformal radiation dose with a rapid dose fall off, 4) daily imaging that allows for repositioning from simulation to treatment, 5) accurate and precise dose-calculation algorithms, and 6) a vigorous quality assurance program. Lung SABR was introduced at our centre in 2007 and thus far 92 patients have been treated. There are currently three treatment machines capable of performing this procedure.
BENEFITS/CHALLENGES: Patient immobilization through the use of body cushions, accurate tumor and organ delineation via the use of four-dimensional computed tomography simulation, development of firm treatment planning guidelines, treatment verification using cone beam computed tomography, and a robust quality assurance program have all been instrumental in ensuring the safe and effective delivery of lung SABR. However, the process was laden with challenges, from delineating the optimum immobilization technique that balances patient comfort and motion, to introducing ways of making novice staff comfortable with a new method for treatment verification.
There are outcome and toxicity data being collected on patients undergoing lung SABR at our cancer centre. This will serve as a self-assessment tool for our implementation process. Moreover, as future indications for SABR change, this initial implementation step will serve as a framework on which to continue building comprehensive guidelines.
对于无法手术的Ⅰ期（T1-T2，N0，M0）非小细胞肺癌患者，立体定向消融放疗（SABR），也称为立体定向体部放疗（SBRT），已显示出与手术相似的生存结果。肺部SABR是一种技术上具有挑战性的方法，用于向小肿瘤体积输送精确的高剂量辐射。在许多癌症中心，SABR的广泛应用受到实施过程复杂性的阻碍。本研究旨在提供一份详细指南，介绍以可靠且高效的方式实施肺部SABR所涉及的步骤。
在我们的癌症中心执行这个复杂的治疗方案需要多学科团队的协作。放射肿瘤学领域的几位专业人员的投入是必要的，包括医学物理学家、剂量师、放射治疗师、护士和放射肿瘤学家。已经制定了专家指南，对该过程的每一步都进行了仔细考虑，包括1）可靠且可重复的患者固定；2）一种考虑肿瘤和器官运动的方法；3）使用多个治疗野以快速剂量下降方式输送高度适形的辐射剂量；4）每日成像以便从模拟到治疗进行重新定位；5）准确且精确的剂量计算算法；6）严格的质量保证计划。肺部SABR于2007年在我们中心引入，迄今为止已治疗了92名患者。目前有三台治疗机器能够执行此程序。
益处/挑战：通过使用身体垫进行患者固定、通过使用四维计算机断层扫描模拟精确描绘肿瘤和器官、制定严格的治疗计划指南、使用锥形束计算机断层扫描进行治疗验证以及强大的质量保证计划，所有这些都有助于确保肺部SABR的安全有效实施。然而，这个过程充满了挑战，从确定平衡患者舒适度和运动的最佳固定技术，到引入让新手工作人员适应新的治疗验证方法的方式。
我们癌症中心正在收集接受肺部SABR患者的疗效和毒性数据。这将作为我们实施过程的自我评估工具。此外，随着SABR未来适应症的变化，这一初始实施步骤将作为继续构建综合指南的框架。
