分段读出扩散峰度成像与前列腺癌Gleason评分相关性的初步研究

A Preliminary Study in Prostate Cancer:the Correlation Between Quantitative Parameters of RESOLVE-Based Diffusional Kurtosis Imaging and Gleason Score

目的探讨分段读出扩散峰度成像(RESOLVE-DKI)定量参数在前列腺癌不同Gleason评分(GS)组间的差异及其相关性。方法搜集经直肠超声引导下前列腺系统穿刺活检病理证实的前列腺癌35例(48个癌灶),在各参数图上分别测出癌灶的DKI定量参数(K值和D值)及表观扩散系数(ADC)值。应用单因素方差分析(ANOVA)比较不同Gleason评分组癌灶的DKI定量参数K值和D值及ADC值间的差异,各Gleason评分组两两间的差异,采用LSD-t检验,P<0.05为差异有统计学意义。采用Pearson相关分析评价癌灶的DKI定量参数K值和D值及ADC值与Gleason评分的相关性。采用受试者工作特征曲线(ROC)比较上述各参数鉴别高分化组(GS≤6)与中低分化组(GS≥7)前列腺癌的诊断效能。结果 K值和D值及ADC值在各GS组癌灶中的差异均有统计学意义(P<0. 05),其中K值的差异有显著统计学意义(P<0.001)。K值在高分化组(GS≤6)与低分化组(GS≥8)、中分化组(GS=7)与低分化组(GS≥8)癌灶间的差异均有统计学意义(P<0.05);而D值和ADC值仅在高分化组(GS≤6)与低分化组(GS≥8)癌灶间有统计学差异(P<0.05)。K值与Gleason评分呈正相关,相关系数为0.823(P<0.001)。ROC曲线得出K值的曲线下面积(AUC)最大,值为0.905,敏感度为95.2%,特异度为81.8%。结论 RESOLVE-DKI定量参数K值对前列腺癌侵袭性的评估和预测具有潜在的临床应用价值。

Objective To explore the difference and correlation of quantitative parameters of readout segmentation of long variable echo-trains(RESOLVE)-based diffusional kurtosis imaging(DKI)in different Gleason scores of prostate cancer.Methods A total of 35 patients(48 lesions)with prostate cancer confirmed by pathology were included in this study.All patients underwent pelvis 1.5-T magnetic resonance imaging,including conventional DWI(b=800 s/mm^2)and RESOLVE-DKI.ROIs were drawn on ADC and DKI maps to measure ADC、D and K values.Apparent diffusion coefficient(ADC)value was derived using a monoexponential model,while diffusion coefficient(D)value and kurtosis(K)value were determined with DKI model.Parameters of prostate cancer zone were compared with ANOVA and LSD-t test,Pearson test was used to evaluate the association among different Gleason scores.The receiver operating characteristic(ROC)curve was used to compare the diagnostic efficacy of the above parameters between highly differentiated group(GS≤6)and moderately poorly differentiated group(GS≥7).Results The difference of K value,D value and ADC value between the GS groups were statistically significant(P<0.05),among which the K value was significantly different(P<0.001).The K values were significantly different between the well-differentiated group(GS≤6)and poorly differentiated group(GS≥8),moderately differentiated group(GS=7)and poorly differentiated group(GS≥8)(P<0.05);D and ADC values were only statistically different between the well-differentiated group(GS≤6)and the poorly-differentiated group(GS≥8)(P<0.05).The K value was positively correlated with the Gleason score,and the correlation coefficient was 0.823(P<0.001).while the D and ADC values were negatively correlated with the Gleason score(r=0.461,r=0.620).The area under the curve(AUC)obtained by the ROC curve of K value was the highest,with a value of 0.905,a sensitivity of 95.2%,and a specificity of 81.8%.Conclusion The K value of RESOLVE-DKI has potential clinical value in evaluating and predicting the invasiveness of prostate cancer.