PET/MR study of Metastatic Lymph Nodes in Head and Neck Cancer

描述(申请人提供)：头颈部癌症约占美国每年确诊的浸润性癌症(约55,000名患者)的3%。所有患者中约有三分之二患有局部晚期疾病。治愈头颈癌的最好机会通常是一开始就积极治疗，包括彻底的淋巴清扫。准确识别淋巴结转移是制定治疗计划和评估治疗反应的关键步骤。在手术前了解淋巴结转移的范围有助于避免不必要的淋巴结切除。然而，目前的成像方法不足以在诊断成像和治疗后评估中对转移结节进行可靠的评估。这项研究的主要目标是开发PET/MR技术，用于准确、非侵入性地检测淋巴结转移，用于治疗规划和评估治疗后转移结节中的残留肿瘤，从而可以最大限度地减少不必要的结节切除。一台最先进的PET/MR扫描仪将在一个疗程内同时获取PET和MRI数据。我们的中心假设是，FDG-PET和DCE-MRI测量的联合模型可以比单独使用FDG-PET或DCE-MRI更准确地检测转移淋巴结。当在一个环境中同时进行PET和MRI扫描时，这一假设可以得到最好的检验，因为它可以将单独的PET和MRI扫描之间在肿瘤微环境方面的任何生理差异降至最低，此外还可以减少参与扫描的患者的就诊次数。我们建议对50例计划行全淋巴结清扫手术的头颈部癌症患者进行动态PET/MR扫描，以便将切除结节的病理评估作为评估PET/MR测量准确性的参考标准。术中记录结节节段，用于PET/MR与病理对照。研究的第一阶段(目标1)是评估FDG-PET和DCE-MRI相结合的测量方法能够比单独使用FDG-PET或DCE-MRI更准确地识别转移结节的程度。目的2确定FDG-PET和DCE-MRI动力学参数之间的关系，并探讨两者的互补作用。联合分析的转运速率常数将与免疫组织化学染色的肿瘤细胞膜上葡萄糖转运体的表达水平进行比较。如果成功，这项提案中的研究将建立一种更可靠、更准确的方法来非侵入性地检测头颈部癌症的转移淋巴结。这种方法还可以扩展到评估其他类型癌症的诊断和治疗后评估的淋巴结转移。

DESCRIPTION (provided by applicant): Head and neck cancers represent approximately 3% of invasive cancers (about 55,000 patients) diagnosed annually in the United States. Approximately two thirds of all patients present with locally advanced disease. The best chance for cure of head and neck cancer is typically aggressive treatment at initial presentation including complete lymph node dissection. Accurate identification of nodal metastases is a crucial step for treatment planning and evaluation of therapy response. Knowledge of the extent of nodal metastases prior to surgery can help avoid unnecessary removal of lymph nodes. However, current imaging methods are not adequate for reliable assessment of metastatic nodes in both diagnostic imaging and post-treatment evaluation. The overarching goal of this study is to develop PET/MR techniques for accurate, non-invasive detection of nodal metastases for treatment planning and assessment of residual tumor in metastatic nodes after treatment, such that unnecessary removal of nodes can be minimized. A state-of-the-art PET/MR scanner will be utilized to acquire PET and MRI data simultaneously within one session. Our central hypothesis is that a combined model of FDG-PET and DCE-MRI measures can detect metastatic nodes more accurately than FDG-PET or DCE-MRI alone. This hypothesis can be best tested when both PET and MRI scans are simultaneously conducted in one setting, as it can minimize any physiological difference in tumor microenvironment between separate PET and MRI scans, in addition to the benefit of fewer visits for the participating patients. We propose to conduct dynamic PET/MR scans with head and neck cancer patients (n=50) scheduled for full node dissection surgery so that pathological evaluation of dissected nodes can be used as the reference standard to evaluate the accuracy of PET/MR measures. During the surgery, the level of nodes will be recorded for level- to-level comparison between PET/MR and pathology evaluation. The first phase of the study (Aim 1) is to assess the extent of which a combination of FDG-PET and DCE- MRI measures can identify metastatic nodes more accurately than FDG-PET or DCE-MRI alone. Aim 2 is to determine the association between the kinetic parameters of FDG-PET and DCE-MRI and investigate the complimentary roles of FDG-PET and DCE-MRI parameters. Transport rate constant from the proposed joint analysis will be compared with the expression level of glucose transporters on the tumor cell membrane using immunohistochemistry staining. If successful, the research in this proposal will establish a more reliable and accurate method to non-invasively detect metastatic lymph nodes in head and neck cancer. This method can then also be extended to evaluating nodal metastasis for diagnosis and post-treatment evaluation in other types of cancer.