DCE-MRI药代动力学定量分析与乳腺导管内癌发生与转归机制的相关性研究

The relationship between atypical ductal hyperplasia (ADH), invasive ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS) is complicated, not simply following a linear evolution as ADH-DCIS-IDC. How to identify the ADH and DCIS lesions that have potential to progress into IDC is crucial for appropriate treatment of DCIS. The pharmacokinetics parameters of DCE-MRI, including Ktrans、Kep、Ve can be used to quantify the distribution and clearance of contrast medium. These parameters can reflect the tightness of junction between vascular endothelial cells. Researches on molecular genetics have revealed that there were chromosomal changes in patients with ADH or DCIS that have been progressed. Therefore, the aim of this research is to study the correlation between imaging characteristics and the mechanism of genesis and outcome of DCIS by analyzing the correlation between pharmacokinetics parameters of DCE-MRI (Ktrans、Kep、Ve) and chromosomal changes, and to provide reliable imaging information for the early diagnosis and appropriate prevention, treatment of DCIS.

乳腺导管内癌（DCIS）与不典型增生（ADH）、浸润性导管癌（IDC）之间关系复杂，并非仅仅遵循ADH-DCIS-IDC的线性演变进程，如何识别哪些ADH和DCIS会进展为IDC，对于DCIS的合理治疗至关重要。DCE-MRI药代动力学指标Ktrans、Kep、Ve可以定量分析对比剂在体内的分布和清除，反映血管内皮细胞间连接的紧密程度，与肿瘤新生血管及其浸润性具有相关性，而分子遗传学研究表明ADH和DCIS发生浸润者染色体会发生改变。因此，我们通过分析DCE-MRI药代动力学指标Ktrans、Kep、Ve与染色体改变的关系来进一步研究其与DCIS的发生与转归机制的相关性，为乳腺癌的预防、早期诊断和合理治疗提供可靠的影像学依据。

本研究使用CDT-VIBE序列，首先通过调整动态扫描参数，确定最佳标准扫描序列，以此为基础观察药代动力学参数Ktrans、Kep、Ve 在乳腺良恶性病鉴别诊断中的价值，及其与IDC、DCIS和ADH患者染色体改变的相关性，并试图通过组间比较寻找相关性，并通过随访、复查等方法纵向观察DCIS病变的发生和转归机制。结果发现，扫描时长及时间分辨率的选择对Ktrans、kep及ve具有显著的影响：扫描时长在5min以上、时间分辨率短于24s时获得的药代动力学参数及其诊断能力可能不会存在明显差异，否则各参数在乳腺良恶性病变之间的区分度及其诊断能力将显著降低。Ktrans及kep在鉴别ADH、DCIS 和IDC中均具有较高的诊断价值，而且kep的准确性要优于Ktrans，但要体现出kep的这些优势必须使用足够的扫描时长。ve值并无明确的诊断价值。研究并未发现药代动力学参数与IDC、DCIS和ADH患者染色体异常之间具有显著的相关性。由于研究时间较短，未能收集到足够的数据观察DCIS的发生与转归机制。