Quantitative MRI for structural and functional characterization of head and neck cancer for outcome prediction and biological individualization of MR-guided radiotherapy

该研究项目的重点是使用混合1.5 T MR-Linac系统对头颈癌（HNC）患者进行定量磁共振成像（MRI），以进行结构和功能肿瘤表征。将开发成像方案和序列，以允许在MR-Linac分次放疗（RT）期间评估HNC患者中基于MR的定量成像生物标志物（QIB），例如表观扩散系数（ADC）、T1、T2和T2* 标测。将启动一项重测患者研究，以评估所有QIB以及RT之前和期间肿瘤体积的稳健性、再现性和变异性。此外，将研究定量MRI测量与最先进诊断MR扫描仪的可比性。在后续临床研究的背景下，该项目的最终目标是确定QIB对RT结局的潜在预后价值，以便整合创建一种新型肿瘤控制概率（TCP）模型，该模型将基于MR的QIB与结局联系起来，作为未来外部验证和后续干预措施（如局灶剂量递增（生物增强，剂量涂抹））的基础。最后，定量MRI技术的方法学结果以及本项目中获得的有关基于MR的反应评估和TCP建模的知识将转移到该联合申请的其他项目中，包括MR引导RT背景下的不同癌症类型和临床应用。

This research project focusses on quantitative magnetic resonance imaging (MRI) for structural and functional tumour characterisation using a hybrid 1.5 T MR-Linac system in head and neck cancer (HNC) patients. Imaging protocols and sequences will be developed to allow the assessment of MR-based quantitative imaging biomarkers (QIB) such as Apparent Diffusion Coefficient (ADC), T1-, T2- and T2*-mapping in HNC patients during fractionated radiotherapy (RT) at the MR-Linac. A test-retest patient study will be initiated to assess robustness, reproducibility and variability of all QIB as well as tumour volume before and during the course of RT. Furthermore, comparability of quantitative MRI measurements with state-of-the-art diagnostic MR scanners will be investigated. In the context of a subsequent clinical study, the ultimate goal of this project is to determine the QIB’s potential prognostic value with respect to RT outcome in order to be integrated to create a novel tumour control probability (TCP) model which links MR-based QIB with outcome as the basis for future external validation and subsequent interventions such as focal dose escalation (bio-boost, dose painting). Finally, methodological results on quantitative MRI techniques as well as knowledge gained in this project on MR-based response assessment and TCP modelling will be transferred to other projects of this joint application including different cancer types and clinical applications in the context of MR-guided RT.