DIFFUSION MRI AS BIOMARKER FOR THERAPY RESPONSE IN BREAST CANCER METASTASES

描述（由申请人提供）：21世纪对肿瘤学家的挑战将是患者护理的个性化。在某些癌症中，治疗决策已经基于患者的生化指标以及这些指标对治疗的反应。显然，开发非侵入性和稳健的方法来监测治疗反应将有助于个体化癌症治疗的整体护理。如果这种方法被开发出来，患者可以继续接受成功的治疗，并从被证明无效的治疗中改变过来。我们假设，扩散MRI，测量组织水的表观扩散系数（ADC），有很大的潜力成为一个有效的癌症化疗的非侵入性标记。大量的临床前数据表明，成功的抗癌化疗后，肿瘤水的ADC会升高。基于这些数据的强度，已提出ADC的变化作为临床环境中缓解的定量生物标志物。来自一些研究小组的初步人体数据支持这一假设，即ADC的早期增加可以预测最终的临床获益。我们小组通过关注转移性乳腺癌为这一奋进做出了贡献。我们关注这种疾病的背景主要是因为有治疗选择，因此，患者可以从应答（或无应答）的知识中受益。在初步的数据中，我们观察到治疗相关的ADC值的变化，扩散MR图像从常见的转移部位的肝脏和骨的乳腺癌患者。该提案的目的是扩展这项工作，以确定ADC的早期变化是否可以定量预测乳腺癌肝（Aim 1）、骨（Aim 2）和脑（Aim 3）转移的临床反应。第四个目标是专注于开发更复杂的图像分析工具，目标是从DWMRI数据集中提取最多的信息。当前方案将使用具有已知缓解率的获批治疗，以验证弥散MRI作为缓解生物标志物。如果本研究证明合理，将在一项多中心试验中进行进一步验证，该试验旨在测试弥散MRI是否可用于监测常规临床实践以及实验性治疗试验中的治疗反应。

DESCRIPTION (provided by applicant): A challenge to oncologists in the 21st century will be the individualization of patient care. Already in some cancers, treatment decisions are based on patients' biochemical indicators at presentation and the response of these indicators to therapy. Clearly, the development of non-invasive and robust methods to monitor therapeutic response would be helpful to the overall care of individualizing cancer treatment. If such methods were developed, patients could be continued on successful therapies and changed from therapies that are proving ineffective. We hypothesize that diffusion MRI, which measures the apparent diffusion coefficient (ADC) of tissue water, has great potential to be a non-invasive marker for effective cancer chemotherapy. A significant amount of pre-clinical data indicates that the ADC of tumor water becomes elevated after successful anti-cancer chemotherapy. Based on the strength of these data, changes in ADC have been proposed as a quantitative biomarker for response in a clinical setting. Preliminary human data from a few research groups supports the hypothesis that early increases in ADC can predict ultimate clinical benefit. Our group has contributed to this endeavor by focusing on metastatic breast cancer. We have focused on this disease setting primarily because there are therapeutic choices, and hence, patients could benefit from knowledge of response (or non response). In preliminary data, we have observed therapy related changes in ADC in diffusion MR images from the common metastatic sites of liver and bone from breast cancer patients. The purpose of this proposal is to expand on this work to determine if early changes in the ADC can quantitatively presage clinical response in liver (Aim 1), bone (Aim 2) and brain (Aim 3) metastases of breast cancer. A fourth aim is focused on developing more sophisticated image analysis tools with the goal of extracting the most information from DWMRI datasets. The current protocol will use approved therapies with known response rates in order to validate diffusion MRI as a response biomarker. If justified from this study, further validation will be pursued in a multicenter trial designed to test if diffusion MRI will be useful to monitor therapeutic responses in routine clinical practice as well as in trials of experimental therapies.