A new imaging approach to radiotherapy planning for lung cancer

 描述(申请人提供)：非小细胞肺癌(NSCLC)占肺癌病例的85%-90%。在其他治疗方法中，非小细胞肺癌通常采用放射治疗(RT)。近年来，在治疗室中，通过适形剂量技术的发展，放射治疗得到了实质性的改善，允许根据目标体积的方向进行空间靶向和调制辐射。然而，这些创新还没有与规划阶段的相应进展充分匹配，规划阶段确定了放射治疗剂量的确切分布。这一生物工程研究伙伴关系应用程序寻求通过结合新的成像数据来增强RT计划过程。NSCLC的放射治疗面临着双重挑战：(A)使剂量的空间和强度与肿瘤的位置、转移潜能和放射抵抗相匹配，以及(B)将剂量限制在具有重要功能的肺组织上，因为辐射可能会对肺组织造成不可修复的损害。目前，靶体积和功能区的定义是使用通过计算机断层扫描(CT)产生的解剖图像，最近从正电子发射断层扫描(PET)获得的代谢图像已经开始被结合。然而，可用于非小细胞肺癌RT计划的肺部数据仍然有限。因此，拟议的研究将超极化磁共振(HP MR)成像/光谱学应用于规划过程。Hp 13C MR能够提供代谢组织对比，包括乳酸生成和pH，这可以指示癌症的存在、侵袭性和辐射抗性。在非小细胞肺癌和放射治疗的情况下，HP气体MR提供了肺功能和微结构的定量数据，可以比单独使用CT更详细地反映区域气体交换的质量。以精炼和评估基于HP-MR的RT规划为最终目标，拟议的项目将追求三个目标。首先，我们将使用HP MR参数来评估辐射对肺的代谢、功能和微结构的影响。其次，我们将建立非小细胞肺癌的大鼠模型，用HP MR成像，然后分成接受不同剂量RT的队列；然后再对每个队列进行成像，以确定辐射剂量、HP MR参数和NSCLC结果之间的相关性。最后，利用前两个目标的结果，我们将为包含HP MR数据的NSCLC模型创建自定义RT计划，并纵向比较它们与传统基于CT的计划在控制肿瘤生长和避免辐射诱导的肺损伤方面的有效性。

 DESCRIPTION (provided by applicant): Non-small cell lung cancer (NSCLC) makes up 85-90% of lung cancer cases. NSCLC is frequently treated with radiation therapy (RT), among other approaches. In the treatment room, RT has been substantially improved in recent years through developments in conformal dosage technology, allowing radiation to be spatially targeted and modulated according to the orientation of the target volume. However, these innovations have not been adequately matched by corresponding advancements in the planning phase, which determines exactly where RT dose will be distributed. This Bioengineering Research Partnership application seeks to enhance the RT planning process through the incorporation of novel imaging data. Radiation therapy for NSCLC faces the twin challenges of (a) matching the spatiality and intensity of dosage to the location, metastatic potential, and radioresistance of malignancy, and (b) constraining dosage to functionally important lung tissue, which can be irreparably damaged by irradiation. Currently, the target volume and functional areas are defined using anatomical images produced via computed tomography (CT), and recently metabolic images derived from positron emission tomography (PET) have begun to be incorporated. However, the pulmonary data available for NSCLC RT planning remains limited. As such, the proposed research applies hyperpolarized magnetic resonance (HP MR) imaging/spectroscopy to the planning process. HP 13C MR is capable of providing metabolic tissue contrasts including lactate production and pH, which can indicate the presence, aggressiveness, and radioresistance of cancer. HP gas MR supplies quantitative data on lung function and microstructure in the presence of NSCLC and irradiation, which can provide a much more detailed reflection of regional gas exchange quality than the use of CT alone. With the ultimate goals of refining and evaluating HP-MR-based RT planning, the proposed project will pursue three aims. First, we will assess the metabolic, functional, and microstructural effect of irradiation on the lung using HP MR parameters. Second, we will induce rat models of NSCLC, which will be imaged with HP MR and subsequently split into cohorts receiving varying levels of RT dose; each cohort will then be imaged again to ascertain correlations between radiation dose, HP MR parameters, and NSCLC outcomes. Finally, using the results of the first two aims, we will create custom RT plans for NSCLC models incorporating HP MR data and longitudinally compare their effectiveness to conventional CT-based plans in terms of their ability to control tumor growth and avoid radiation-induced pulmonary damage.