3.0T高分辨磁共振成像在直肠癌T分期及分化程度差异分析中的应用

Application of 3.0T High Resolution Magnetic Resonance Imaging in the Analysis of Difference of T Stage and Degree of Differentiation of Rectal Carcinoma

目的探究高分辨磁共振成像在直肠癌肿瘤T分期及分化程度差异分析中的意义。方法回顾性分析48例直肠癌病人的临床和影像学资料。将磁共振单纯T2加权像(T2WI)与T2WI结合弥散加权成像(diffusion weighted imaging,DWI)两种成像方式确诊直肠癌T分期的正确率进行比较,分析直肠癌DWI的指数化表观扩散系数(exponential apparent diffusion coeffcient,eADC)、表观扩散系数(apparent diffusion coeffcient,ADC)与T分期的关联性;分析eADC值、ADC值与直肠癌有无远处转移及其分化程度是否相关。结果单独T2WI与T2WI结合DWI两种成像方式确诊直肠癌T分期正确率分别为77.1%、85.4%,两种方法的结果具用关联性(χ~2=22.693,P<0.01,C=0.956),两种方法检出正确率差异无统计学意义(P=0.125)。直肠癌在DWI图像上(b=1000s·mm^(-2)),均表现为高信号,病理T1、T2、T3和T4分期直肠癌平均ADC值依次减低,eADC值依次升高(P<0.05)。不同分化程度的直肠癌患者的ADC值、eADC值差异有统计学意义(b=1000s·mm^(-2)),(χ~2=8.256,P=0.016;F=4.915,P=0.012)。无转移组和有转移组直肠癌患者病灶ADC值和eADC值差异均无统计学意义(P均>0.05)。结论 DWI可在某种程度上提高常规T2WI序列对于直肠癌T分期的确诊;ADC值及eADC值与肿瘤的T分期及分化程度有关。

Objective To investigate the significance of high-resolution magnetic resonance imaging in the analysis of difference of the T stage and degree of differentiation of rectal cancer.Methods The clinical and imaging data of 48 patients with rectal cancer was retrospectively analyzed.The diagnostic accuracy of T staging of rectal cancer was compared between pure T2 weighted imaging(T2WI)and diffusion weighted imaging(DWI).The correlation between exponential apparent diffusion coeffcient(eADC),apparent diffusion coeffcient(ADC)and T staging of rectal cancer was analyzed.Whether eADC value and ADC value were correlated with distant metastasis and differentiation of rectal cancer were analyzed.Results The T2WI and T2WI combined with DWI imaging methods for the diagnosis of rectal cancer T-stage coincidence rates were 77.1%and 85.4%,respectively.After paired four table chi-square tests,the results of the two methods were correlated(χ^2=22.693,P=0.000),but the detection accuracy of the two methods was not statistically significant(P>0.05).Rectal cancer showed high signal on DWI images(b=1000s·mm^-2).The average ADC value of rectal cancer in pathological T1,T2,T3 and T4 stages gradually decreased,and the average eADC value gradually raised,and the difference was statistically significant(P<0.01 or<0.05).The difference in ADC value and eADC value between patients with different degrees of differentiation was statistically significant(b=1000 s·mm^-2),(χ^2=8.256,P=0.016;F=4.915,P=0.012).There was no statistical significance on ADC and eADC values between the presence or absence of rectal cancer distant metastasis(P>0.05).Conclusion DWI can improve the diagnosis of rectal cancer T staging by increasing the conventional T2WI sequence to some extent.The ADC value and eADC value are closely related to the T stage and differentiation of the tumor.