Comparison of cone beam and fan beam (tomotherapy) adaptive radiotherapy: physical and clinical developments and evaluation of new approaches of intensity modulated raditotherapy

断层治疗是一种新的放射治疗形式。虽然仍处于临床初期，但初步结果令人鼓舞。将临床上级辐射输送装置的潜力与目前的线性加速器辐射输送以及质子和重离子辐射所承诺的临床治疗可能性进行比较。应根据临床需求提供治疗方式的排序。断层治疗结合了计算机断层扫描与放射输送系统。该设备将治疗计划、患者定位和治疗交付集成到一个系统中。它有可能显着改善患者护理凭借其提高精度的治疗交付，这可能会导致减少毒性和剂量递增。虽然临床医生对这些潜在的临床获益持乐观态度，但这一点尚未确定。此外，在临床中引入断层治疗所导致的实践变化可能会影响目前的组织结构。例如，提高精度可能会减少分数的数量，图像引导的患者定位的影响可能会导致越来越多的虚拟模拟取代立体定向treatment.The的目的是评估未来的作用，断层放射治疗在放射肿瘤学。断层治疗，特别是以螺旋形式提供的断层治疗，代表了一种向任意形状的目标体积提供放射治疗的新方式。我们想证明断层放射治疗的潜在优势，如更高的剂量适形性，以更快的治疗时间更好地保留正常结构在临床条件下保持真实。在线成像的可能性允许校正日常设置不确定性，甚至可以考虑分次内移动。断层治疗需要一个全新的治疗单元，包括治疗计划和实施。目前，正在开发使用配备有多叶准直器的传统线性加速器的治疗递送的不同方法。因此，断层治疗方法的系统评价似乎是合理的。我们建议比较一组参数，其中包括医学物理特性，治疗计划参数，放射生物学实验，社会经济考虑和应用的安全性，以及断层治疗方法与有经验的用户手中的直线加速器和离子束的IMRT的临床结果。临床研究将集中在乳腺癌，前列腺癌，肺癌（包括间皮瘤），上胃肠道肿瘤、前列腺癌和CNS肿瘤。患者将被纳入I/II期和随机化II期研究。其目的是确定将从一种或另一种形式的放射治疗中受益的患者的特征，并预测这些患者的最佳模式。最后，应该估计最终需要的断层治疗单位的数量。

Tomotherapy is a new form of radiation delivery. Although still in its clinical infancy, preliminary results are encouraging. The potential of a clinical superior radiation delivery device is to be compared with the present day linear accelerator radiation delivery and the clinical treatment possibilities promised by proton and heavy ion irradiation. A ranking of treatment modalities depending on the clinical demands should be provided. Tomotherapy combines computed tomography with a radiation delivery system. The unit integrates treatment planning, patient positioning, and treatment delivery into one system. It has the potential to significantly improve patient care by virtue of its increased precision in treatment delivery, which may result in reduced toxicity and dose escalation. While clinicians are optimistic about these potential clinical benefits, this has not yet been established. Further, changes in practice resulting from the introduction of tomotherapy in the clinic would likely impact the current organizational structure. For example, increased precision may allow a reduction in the number of fractions, the impact of image guided positioning of the patient may lead to a rising number of virtual simulations replacing stereotatic treatments.The aim of this proposal is to evaluate the future role of tomotherapy in radiation oncology. Tomotherapy especially delivered in its helical form represents a new way to deliver radiation therapy to arbitrarily shaped target volumes. We want to show if potential advantages of tomotherapy such as higher dose conformality to the target volume and better sparing of normal structures at faster treatment time hold true under clinical conditions. The possibility of online imaging allows for correction of daily setup uncertainties and even may allow to take into account intrafractional movement. The tomotherapy requires a whole new treatment unit which includes the treatment planning and delivery. Currently different approaches of treatment delivery with conventional linearaccelerators equipped with multileafcollimators are being developed. Therefore a systematic evaluation of the tomotherapy approach seems to be justified. We propose to compare one set of parameters which includes medical physics characteristics, treatment planning parameters, radiobiological experiments, socioeconomical considerations and the safety of application and also clinical results of the tomotherapy approach to that of IMRT with linacs and ion beams in the hands of experienced users.The clinical studies will focus on breast cancer, prostate cancer, lung cancer including mesothelioma, upper gastrointestinal tract tumors, prostate cancer and CNS tumors. Patients will be included in phase I/II and in randomized phase II studies. The aim is to identify the characteristics of patients who will benefit from one or the other form of radiation therapy and to predict the best modality for these patients. Finally the number of tomotherapy units which would be eventually necessary should be estimated.