多b值DWI在肾透明细胞癌Fuhrman核级诊断中的应用研究

Application of DWI with various b values in diagnosis of clear cell renal cell carcinoma Fuhrman grades

背景与目的:肾细胞癌是成人最常见的肾脏恶性肿瘤,而Fuhrman核级系统是得到广泛认可的肾细胞癌预后判断的独立指标之一。本文旨在探讨多b值磁共振弥散加权成像(diffusion weighted imaging,DWI)与肾透明细胞癌clear cell renal cell carcinoma,CCRCC)Fuhrman核级的相关性,评价各指标在鉴别Fuhrman核级高级别与低级别肿瘤中的诊断效能。方法:选取经病理证实为CCRCC的患者33例,后处理选择不同b值组合测量肿瘤ADC值,分析其与Fuhrman核级相关性。应用受试者操作特征性曲线评价不同b值组合所得ADC值在鉴别Fuhrman核级低级别(1、2级)及高级别(3、4级)CCRCC中的诊断效能。通过约登指数得出各参数的灵敏度和特异度。结果:在33例CCRCC患者中,Fuhrman核级1级1例、2级14例、3级16例、4级2例,不同b值所得肿瘤ADC值(ADC_(0-800)ADC_(0-400-800)ADC_(0-600-1200)、ADC_(0-400-800-1200)及ADC_(tatal))与肿瘤Fuhrman核级均为负相关,相关系数分别为-0.553、-0.511、-0.603、-0.645、-0.610,其中ADC_(0-400-800-1200)的相关系数绝对值最高。Fuhrman高级别组CCRCC的ADC值均明显低于低级别组,差异有统计学意义(P<0.05)。各ADC值的受试者工作特征性曲线(receiver operator characteristic curve,ROC曲线)的曲线下面积(area under the curve,AUC)分别为0.789、0.757、0.813、0.844、0.835,以ADC_(0-400-800-1200)最大,但是各AUC差异无统计学意义(P>0.05)。各ADC值鉴别CCRCC高、低级别的灵敏度分别为86.7%、73.3%、60.0%、86.7%和86.7%;特异度分别为66.7%、77.8、72.2%、77.8%和72.2%。结论:ADC_(0-800)、ADC_(0-400-800)、ADC_(0-600-1200)、ADC_(0-400-800-1200)、ADC_(tatal)与肿瘤Fuhrman核级均具有显著相关性,并在鉴别Fuhrman核级高级别与低级别肿瘤中具有较高的诊断效能。

Background and purpose：Renal cell carcinoma is the most common type of adult renal cancer, and the Fuhrman grading system is the most widely accepted independent indicator for the prognosis of kidney tumors. This study aimed to explore the correlation between the conventional diffusion weighted imaging （DWI） with various b values and Fuhrman grade of clear cell renal cancer, and assess the diagnostic efifciency of ADC values at different b values in differentiating Fuhrman low- and high-grade tumor. Methods：Thirty-three patients with pathologically proved clear cell renal cell cancer （CCRCC） and qualiifed images were included for the research. The diagnostic efif-ciency of ADC values at different b values for differentiating Fuhrman low-（1 and 2） and high-grade （3 and 4） tumor were also assessed and compared by receiver operator characteristic curve （ROC）, and the optimum sensitivity, speciifc-ity and accuracy were selected using Youden index. Results：The 33 patients consist one tumor of Fuhrman grade 1, 14 of grade 2, 16 of grade 3 and 2 of grade 4. A negative correlation was found between the ADC0-800, ADC0-400-800, ADC0-600-1 200, ADC0-400-800-1 200 and ADCtotal with Fuhrman grade （r：-0.553,-0.511,-0.603,-0.645,-0.610, respectively）, among these the ADC0-400-800-1200 showed the strongest correlation. The AUCs [area under the （receiver operator characteristic curve） ROC curve] of those parameters for differentiating the low-and high-grade tumor were 0.789, 0.757, 0.813, 0.844 and 0.835, among which the ADC0-400-800-1 200 reveal the best result, but the difference was not statistically signif-icant （P〉0.05）. The sensitivity of the ADC values were 86.7%, 73.3%, 60.0%, 86.7%and 86.7%;The speciifcity were 66.7%, 77.8, 72.2%, 77.8%and 72.2%. Conclusion：ADC0-800, ADC0-400-800, ADC0-600-1 200, ADC0-400-800-1 200 and ADCtotal re-vealed signiifcant correlation with the Fuhrman grade of clear cell renal cancer, and providing high diagnostic efifciency in differentiating Fuhrman low-and high-grade tumor.