The Study On The Value Of DKI Quantitative Parameters In The Differential Diagnosis Of Benign And Malignant Ovarian Tumors And Correlation With Ki-67

Objective:To analyze the value of diffusion kurtosis imaging（DKI）and diffusion weighted imaging（DWI）in differentiating benign and malignant ovarian tumors,and the correlation between its parameters and Ki-67 expression level。Methods:48 consecutive patients with pathologically confirmed ovarian tumors,including 23ovarian benign tumors（25 lesions）and 25 malignant tumors（30 lesions）,total 55 lesions.Patients under went pelvic MRI scan,DKI and DWI sequence scan before surgery to obtain the mean diffusivity（MD）value,fractional anisotropy（FA）value,mean kurtosis（MK）value,apparent diffusion coefficient（ADC）value And Ki-67 antigen expression levels of the tumor.Ki-67 immunohistochemical staining was performed on the postoperative pathological specimens.The independent sample t test was used to compare the difference of MK value,MD value,FA value,ADC value and Ki-67between the groups.The ROC curve was used to evaluate the diagnostic efficacy of each parameter in the differential diagnosis of benign and malignant ovarian tumors.Spearman Correlation analysis of each parameter value and Ki-67 correlation。Results:The MK value was significantly higher inmalignant tumor group（0.85±0.1）than in benign tumor group（0.62±0.11）,and the difference was statistically significant（P<0.001）.while the MD and ADC values were significantly lower in malignant tumors group than in benign tumor group(1.54±0.34×10^-3mm²/s vs 1.1±0.29×10^-3mm²/s;1.23±0.19×10^-3mm²/s vs 1.0±0.15×10^-3mm²),the difference was statistically significant（P<0.001）.There was no significant difference in FA values between the benign and malignant groups（P=0.422）.The expression level of Ki-67 in malignant tumor was significantly higher than that in benign tumor group（55.93%±22.12%vs10.04%±5.12%）,The difference was statistically significant（P<0.001）.The area under the ROC curve（AUC）,sensitivity and specificity of MK values were the highest,0.88,0.81 and 0.84,respectively.MK value was positively correlated with Ki-67（r=0.62,P<0.001）.MD value and ADC value was negative correlation with Ki-67（r=-0.55,-0.50,P<0.001）.There was no significant correlation between FA value and Ki-67。Conclusion:DKI and DWI quantitative parameters can reflect the proliferative activity of ovarian tumors,and can be used as an effective biological indicator to identify benign and malignant ovarian tumors.