大鼠肝细胞癌演进过程中的MR成像研究

MRI Study on the Progression of Hepatocellular Carcinoma in Rats

目的 :探讨肝细胞癌 (HCC)演进过程中的MR信号变化及其与癌组织病理分级之间的关系。材料与方法 :用二乙基亚硝胺 (DEN)诱导大鼠HCC ,于不同时相行MR检查 ,并对癌组织作相应的病理分级。结果 :共诱发 5 1个HCC ,T2 WI均呈高信号 ,T1WI分别呈高 (19 6 % )、等 (17 6 % )、低 (6 2 7% )信号 ,其中高信号者于诱癌早期多见 ,病理上多为Ⅰ、Ⅱ级 ,低信号者以晚期多见 ,主要为Ⅲ、Ⅳ级。结论 :低剂量DEN诱导大鼠肝癌模型可作为研究肝癌MR成像的一种手段 ;在HCC的演进过程中其T1WI信号遵循由高到低的规律 ;从T1WI信号特征可间接判断HCC的恶性程度。

Purpose: To study the progression of HCC with MRI and pathology in rats. Materials and Methods: HCCs were induced in rats by diethylnitrosamine (DEN). MR examination as well as pathologic grading was performed on different time of the induction. Results: 51 lesions were detected. On T 2 weighted images all lesions appeared hyperintense. On T 1 weighted images, they showed various signal patterns, including hyperintensity (19.6%), isointensity (17.6%) or hypointensity (62.7%). The hyperintense lesions were found mostly in the early phases and pathologicaly graded as Edmonson Ⅰ～Ⅱ. The hypointense ones were found mostly in later phases, and account for most of those graded as Ⅲ～Ⅳ. Conclusion: The modle of HCC induced by low dose DEN is a helpful form for MRI study of HCC; The signal on T 1 weighted image changes from hyperintensity to hypointensity in the progression of HCC; The malignancy degree of HCC can be determined indirectly according to the signal pattern on T 1 weighted image.