Improving Pancreas RT Plans using Respiration-driven Anatomic Deformation

利用呼吸驱动的解剖变形改进胰腺 RT 计划

• 批准号: 8606447
• 负责人: Wensha Yang
• 金额: $ 7.77万
• 依托单位: CEDARS-SINAI MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8606447
• 关键词: Abdomen; Adverse effects; Algorithms; Anatomy; Breathing; Clinical Trials; Data; Disease; Dose; Dose-Limiting; Duodenum; Excision; Failure; Future; Gastrointestinal tract structure; Geometry; Goals; Grant; Image; Intestines; Intra-abdominal; Lead; Learning; Magnetic Resonance; Magnetic Resonance Imaging; Malignant Neoplasms; Malignant neoplasm of pancreas; Maps; Methods; Motion; Normal tissue morphology; Operative Surgical Procedures; Organ; Pancreas; Pancreatic Adenocarcinoma; Patients; Pilot Projects; Positioning Attribute; Progression-Free Survivals; Radiation; Radiation therapy; Relative (related person); Research; Resectable; Respiration; Respiratory Diaphragm; Risk; Stomach; Stomach Part; Structure; Techniques; Testing; Toxic effect; Treatment Effectiveness; Tumor Tissue; Unresectable; Work; X-Ray Computed Tomography; base; expiration; gastrointestinal; image registration; improved; irradiation; novel; novel strategies; pancreatic neoplasm; public health relevance; respiratory; success; treatment planning; treatment strategy; tumor

DESCRIPTION (provided by applicant): Pancreatic adenocarcinoma is a lethal cancer, with more than 85% of patients presenting with either locally advanced or metastatic disease. Current treatment of locally advanced pancreatic cancer (LAPC) with regular fractionated radiation therapy (RT) results in local failure rates of 40-70%. While local progression free survival approached 100% when stereotactic body radiation therapy (SBRT) with a single dose of 25 Gy was used, the GI toxicities were significant, thus requiring hypo-fractionated (3 to 5 fraction) SBRT for future trials. SBRT treatment requires plans to satisfy stringent normal tissue constraints that are difficult to achieve with conventional planning strategy due to the close proximity of tumor and critical organs. Treatment planning is further complicated by respiration-induced organ motion which forces large margins around tumor, increasing the volume of the normal tissue irradiated and thus increasing the risk of GI toxicity. New treatment planning strategies are clearly needed to overcome these problems. Goals: To gather preliminary dosimetric data for a novel strategy which makes use of respiration-driven anatomic deformation in a "dual instance" method to improve pancreatic treatment plans. The long-term objective is to use the information learned from this pilot grant to screen and treat patients that can potentially benefit from the Dual Instance planning method. Methods: (1) Use magnetic resonance (MR) and computed tomography (CT) imaging to quantify geometric motions and deformations in abdominal structures as patients hold their breath at deep inspiration (INSP) and expiration (EXP). (2) Use an advanced deformation image registration algorithm to map the distortions between INSP and EXP states, so treatment plan dose distributions can be mapped and analyzed. (3). Optimize plans using free breathing, EXP-only, INSP-only, and a novel dual-instance combination of EXP and INSP to study potential improvements in pancreatic tumor dose which can be achieved in one or more of these instances, taking advantage of relative shifts in tumor and critical organ positions. Impact: Success of this pilot study will lay the groud work necessary for use of the improved technique(s) in the follow-on clinical trials which escalate dose to patients with LAPC without increasing toxicity.

描述（由申请人提供）：胰腺腺癌是一种致命的癌症，其中85％以上患有局部晚期或转移性疾病。定期分离放射治疗（RT）的当前治疗局部晚期胰腺癌（LAPC）的局部故障率为40-70％。当使用单剂量为25 Gy的立体定向体放射疗法（SBRT）时，无局部进展生存率接近100％，但GI毒性很大，因此需要进行较低分数（3至5个分数）SBRT进行以后的试验。 SBRT治疗需要计划满足严格的正常组织约束，这些限制因肿瘤和关键器官的近距离而难以实现常规计划策略。呼吸诱导的器官运动进一步复杂化的治疗计划，该运动迫使肿瘤周围的较大边缘增加，从而增加了受辐照的正常组织的体积，从而增加了胃肠道毒性的风险。显然需要新的治疗计划策略来克服这些问题。目标：收集初步的剂量学数据以进行新的策略，该策略在“双重实例”方法中利用呼吸驱动的解剖变形，以改善胰腺治疗计划。长期目标是使用从该试点赠款中学到的信息进行筛查和治疗可能有可能的患者 受益于双实例计划方法。方法：（1）使用磁共振（MR）和计算机断层扫描（CT）成像来量化腹部结构的几何运动和变形，因为患者以深层灵感（INSP）和到期（EXP）呼吸。 （2）使用先进的变形图像登记算法来绘制INSP和Exp状态之间的扭曲，因此可以映射和分析治疗计划剂量分布。 （3）。使用自由呼吸，仅exp-thly，Insp-andly和INSP的新型双构度组合来优化计划，以研究胰腺肿瘤剂量的潜在改进，在其中一个或多个情况下，可以利用肿瘤和关键器官位置的相对转移来实现。影响：这项试验研究的成功将在后续临床试验中使用改进的技术使用所必需的工作，该试验将剂量升级给LAPC患者而不会增加毒性。