Value of multi-phase enhanced MRI combined with histogram analysis of apparent diffusion coefficient in differential diagnosis of intrahepatic biliary cystadenoma and intrahepatic biliary cystadenocarcinoma / 中华放射学杂志

ABSTRACT

Objective To investigate the value of quantitative multi-phase enhanced MRI combined with histogram analysis of ADC in differential diagnosis of intrahepatic biliary cystadenoma (HBCA) and intrahepatic biliary cystadeno carcinoma (HBCAC). Methods Twenty-five patients with pathologically confirmed intrahepatic biliary cystic tumor (HBCT), including 16 cases of HBCA and 9 cases of HBCAC, were retrospectively analyzed. All the patients underwent upper abdominal MR plain scan and multi-phase enhanced scan. The MRI findings of the lesions were observed. The peak contrast enhancement ratio (pCER) of the lesions in the arterial phase, portal venous phase and delayed phase was calculated. ADC histogram analysis was performed and the quantitative parameters were acquired, including the average,standard deviation, median, kurtosis, skewness, and the 10th, 30th,70th, 90th percentile. Qualitative parameters were compared using Fisher exact test. The continuous variables with normal distribution and homogeneous variance were compared by independent sample t test. The continuous variables with skewed distribution were compared by Mann-Whitney U test. The ROC curve analysis was used to evaluate the differential diagnostic ability of the variables with significant differences between HBCA and HBCAC patients.Results There was a statistically significant difference between HBCA and HBCAC in terms of gender, age and whether there was bile duct dilatation or mural nodules (all P<0.05). However, the maximum diameter, high signal intensity of the cystic fluid on T1WI and septa of the lesions were not statistically significant (all P>0.05). The pCER of arterial phase, portal venous phase and delayed phase of HBCAC patients were higher than those of HBCA patients (all P<0.05).The standard deviation of ADC value of HBCAC group was higher than that of HBCA group, while the kurtosis and the 10th percentile were lower than those of HBCA group, and the differences were statistically significant between the two groups (all P<0.05). When the 10th percentile value of ADC histogram was≤ 2.060 × 10-3 mm2/s, the area under the ROC curve of discriminating between HBCA and HBCAC was the largest (0.861), and the diagnostic accuracy, sensitivity and specificity were 84.0 % and 77.8 % and 87.5 %, respectively. Conclusion Quantitative multi-phase enhanced MRI combined with histogram analysis of ADC had certain value for the differential diagnosis of HBCA and HBCAC, and the 10th percentile of the ADC histogram had the best diagnostic efficiency.