体素内不相干运动成像及微血管密度与宫颈癌病理分级的相关性研究

The correlation between intravoxel incoherent motion and microvessel density and pathological differentiation of cervical cancer

目的分析体素内不相干运动成像(intravoxel incoherent motion,IVIM)各成像参数和肿瘤微血管密度(microvessel density,MVD)在宫颈癌分级中的诊断价值,并探讨IVIM各参数与MVD的相关性。材料与方法回顾性分析26例经病理证实为宫颈癌的患者,根据宫颈癌分化程度分为高分化(G1)组、中分化(G2)组及低分化(G3)组。患者均行IVIM-MR检查且具有手术病理蜡块存储的条件,IVIM参数包括慢扩散系数(D)、快扩散系数(D*)、灌注分数(f);用CD34免疫组化染色剂标记宫颈癌肿块内微血管密度;Kruskal-Wallis H检验比较各参数在三组间的差异,应用Spearman秩相关分析研究IVIM各参数、MVD与病理分级的相关性、IVIM参数和MVD间的相关性。结果 IVIM各参数中,D值、D*值在不同分化程度的宫颈癌比较中差异有统计学意义(P=0.009、P=0.003),其中D值在组内两两比较差异有统计学意义(G1与G2组间比较,P=0.032;G1与G3组间比较,P=0.008,G2与G3组间比较P=0.047),D*值在G1及G3分化组间(P=0.003)、G2及G3分化组间比较中差异具有统计学意义(P=0.004),D值随分化级别增高数值减低,D*值随分化级别增高数值逐渐减低。MVD在三组组间比较差异皆具有统计学意义(G1与G2组间比较P=0.002,G1与G3组间比较,P=0.001,G2与G3组间比较P=0.004),IVIM各参数仅D*值与MVD呈直线相关(r~2=-0.554),差异具有统计学意义(P<0.05)。结论 IVIM和MVD对宫颈癌分级具有一定的诊断价值,IVIM参数D*可以用于对肿瘤MVD的评估。

Objective:To analyse the value of intravoxel incoherent motion(IVIM)diffusion weighted imaging and histological microvessel density(MVD)in grading of cervical cancer and to investigate their correlation.Materials and Methods:Twenty-six patients with pathologically proved cervical cancer were analysed retrospectively.They were divided into G1 group(highly differentiated),G2 group(moderately differentiated)and G3 group(poorly differentiated)according to pathology grading of cervical cancer.All patients underwent IVIM MRI.The IVIM parameters(ADC,D,D*,f,fD*)were assessed.And these parameters were correlated with MVD.The MVD were determined with the CD34 stain.Kruskal-Wallis H test was used to compare differences of parameters among three groups.Spearman’s rank correlation analysis was used to evaluate the correlation of parameters and pathology grading and the correlation between IVIM parameters and MVD.Results:IVIM parameters,like D value and D*value,showed statistical difference among three groups(P=0.009、P=0.003).Pairwise comparison showed that D had significant difference(P<0.05).Comparing with G1 and G3,G2 and G3,D*value showed significant difference.D value decreased with the increase of differentiation level(that is,the lowest median value of D value in the low-differentiation group).While the value of D*decreased gradually with the increase of differentiation level.The MVD was statistically significant among the three groups(P<0.05).The correlation between IVIM parameters D*value and MVD was statistically significant(P<0.05),showing a linear correlation(r~2=-0.554).Conclusions:IVIM parameters(D、D*)and MVD have certain diagnostic value for cervical cancer grading.Besides,D*might be used in the noninvasive evalution of MVD.