直肠癌弥散峰度成像与D2-40、CD31、S-100及肿瘤细胞增殖指数的相关性研究

目的探讨弥散峰度DKI参数(diffusion-kurtosis image,DKI)参数与直肠癌免疫组化D2-40、CD31及Ki-67之间的关系。能够在术前评估其表达程度,从而能够间接反映肿瘤细胞的增殖指数等,为临床提供直肠癌术前恶性程度评估的依据。材料与方法搜集2016年1月至9月经病理证实的直肠癌患者69例,所有病例经常规扫描加DKI,得到DKI与扩散张量成像(diffusion tensor imaging,DTI)参数:各向异性指数(fractional anisotropy,FA),垂直扩散张量(radial diffusivity,D⊥)、平均扩散系数(mean diffusivity,MD)、轴向扩散张量(axial diffusivity,D//),平均峰度(mean kurtosis,MK)、径向峰度(radial kurtosis,K⊥)、轴向峰度(axial kurtosis,K//)。免疫组化D2-40、CD31、S-100及Ki-67由Ultra View-DAB染色进行处理得到。D2-40、CD31根据表达分为阴性与阳性组,采用独立样本t检验进行各参数间的对比。用ROC曲线评判各参数对两组的诊断效度,分析各MK等值与Ki-67的关系采用Pearson相关分析法。结果 MK、K⊥在D2-40、CD31阳性组参数值高于阴性对照组,MD在阳性参数组低于阴性参数组,差异有统计学意义(P0.05)。Pearson相关分析法得出Ki-67与D⊥、D//、MD之间呈负相关,而与MK、K⊥、K//之间呈正相关性。应用ROC曲线分析各参数对直肠癌D2-40、CD31表达阴性与阳性的诊断鉴别能力。结论 DKI成像可反映直肠癌组织的复杂程度,可在术前无创地评估免疫组化D2-40、CD31、S-100及Ki-67的表达水平,从而可间接反映肿瘤细胞增殖程度。

Rectal cancer on MRI diffusion-kurtosis imaging and correlation between DKI parameters and D2-40, CD31, S-100 and Ki-67 in rectal tumors

Objective: To evaluate the potential association between DKI parameters and D2-40, CD31, S-100 and Ki-67 with immunohistochemical analysis of rectal cancer. Materials and Methods: Data from 69 patients who were confirmed by surgical pathology from January to September in 2016. All cases were performed by regular sequence and DKI and DTI (diffusion tensor imaging) examination. The following parameters were acquired from the entire tumors. Respectively as Dax, Dmean, Drad, Fa, Kax, Kmean, Krad. D2-40, CD31, S-100 and Ki-67 were detected by Ben CHMARK-XT machine and Mul-timer system. D2-40 and CD31 were divided into two groups according to the expression of positive or negative and independent-sample t test was used for statistical analysis. Receiver operating characteristic curves and Pearson correlation were used for statistical analysis. Results: The levels of MK, K⊥ value in D2-40, CD31 positive group were significant higher than negative group. The differences were statistically significant (P<0.05). Whereas MD in D2-40, CD31, positive group were significantly lower than negative group, the differences were statistically significant (P<0.05). Pearson correlation analysis showed Ki-67 was significant positive correlation with MK, K⊥, K// parameters, whereas Ki-67 showed negative correlation with D⊥, D//, MD. ROC curve was applied to analysis of DKI parameters in D2-40, CD31 positive group and negative group. Conclusions: MK can reflect the tissue microenvironment including its component organelles, cell membranes, and water compartments, maybe preoperative noninvasive assessment of D2-40, CD31, S-100 and Ki-67 expression level, indirectly reflect the degree of tumor cell proliferation, provide a reference for colorectal malignant degree and prognosis of preoperative evaluation basis.