DKI技术在肝外胆管癌分级中的应用价值

Application value of DKI in grading of extrahepatic cholangiocarcinoma

目的探讨扩散峰度成像(diffusion kurtosis imaging,DKI)相关参数D、K值与肝外胆管癌(extrahepatic cholangiocarcinoma,EHCC)病理分级的相关性,并比较参数的诊断效能。材料与方法搜集临床疑诊EHCC患者,行MRI检查(包括常规平扫和DKI序列)及手术治疗,选择满足条件患者35例,经软件处理获得DKI参数D、K值,对照病理结果,评价上述参数值与高、中、低分化肝外胆管腺癌病理分级的相关性,采用ROC曲线来比较参数诊断效能。结果 35例EHCC病理结果包括:Ⅰ级11例,Ⅱ级11例,Ⅲ级13例。Ⅰ级即高分化组病灶相关参数D、K值分别为(1.56±0.08)×10^(–3) mm^2/s、0.38±0.07;Ⅱ级中分化组相关参数值分别为(1.47±0.09)×10^(–3) mm^2/s、0.51±0.08,Ⅲ级低分化组参数值分别为(1.39±0.07)×10^(–3) mm^2/s、0.66±0.08。D、K值在不同分化程度EHCC中存在统计学差异(P<0.001,<0.001),随着病理分化程度的降低,D值逐渐降低,K值则逐渐增加,相关系数分别为0.672、0.848。ROC曲线方法得到D、K值曲线下面积分别为0.860和0.951,且差异存在统计学意义(P<0.001)。结论 K值与病理分化程度相关性好,有助于病理分化程度的术前诊断。

Objective： To evaluate the application value of diffusion kurtosis imaging（DKI） based D, K parameters in grading extrahepatic cholangiocarcinoma（EHCC）and compare their diagnostic potential. Materials and Methods： Thirty-five consecutive patients surgically resected and pathologically confirmed EHCC were included in this study. All patients underwent upper abdomen magnetic resonance imaging, including traditional magnetic resonance imaging and diffusion kurtosis imaging. The DKI derived parameters D, K were calculated by using post-processing software. Compared with histologic grade（well-differentiated, moderately differentiated and poorly differentiated adenocarcinoma）, evaluating the association and compare the diagnostic potential of parameters by using receiver operating characteristic（ROC） analysis. Results： Thirty-five cases of EHCC include： gradeⅠ（well-differentiated adenocarcinoma） 11 cases, grade Ⅱ（moderately differentiated adenocarcinoma） 11 cases and grade Ⅲ（poorly differentiated adenocarcinoma） 13 cases. Grade Ⅰ group lesions parameter D, K values were（1.56±0.08） ×10^–3 mm^-2/s,0.38±0.07. Grade Ⅱ group were（1.47±0.09） ×10^–3 mm^-2/s, 0.51±0.08. Grade Ⅲ group were（1.39±0.07） ×10^–3 mm^-2/s, 0.66±0.08. D and K values were significantly different in well, moderately and poorly differentiated adenocarcinoma（P〈0.001,〈 0.001）.With the reduction of histological differentiation degree, D value decreased, while K value increased（r=0.672, 0.848）. ROC analysis demonstrated a higher area under the ROC curve value for K than for D for differentiating different pathological grade of EHCC（0.860 VS 0.951）. Conclusions： K value of EHCC showed significantly diagnostic performance in differentiating different grade EHCC, and are helpful of pathologic degree in preoperative diagnosis.