Value of diffusion?weighted imaging in the evaluation of therapeutic effect of cyber knife on hepatocellular carcinoma / 中华放射学杂志

ABSTRACT

Objective To investigate the value of DWI in the evaluation of the therapeutic effect of cyber knife in the treatment of hepatocellular carcinoma.Methods Ninety patients who were clinically diagnosed with hepatocellular carcinoma (95 lesions) in the 5th Medical Center of General Hospital of PLA from February 2011 to December 2013 were retrospectively analyzed. All 90 patients underwent pre‐treatment dynamic contrast‐enhanced MRI scans of liver. Fourty six of them underwent liver MRI scan 3 months after treatment with cyber knife, and 49 patients underwent liver MRI scans 6 months after treatment. According to the evaluation criteria of solid tumor effect, complete necrosis tumor lesions and postoperative residual active lesions were determined. The ADC values of residual active tissue lesion, necrosis lesion in tumor and normal liver were measured. Paired sample t test was used to compare the difference of ADC values of tumor necrosis lesions and normal liver tissues between 3 and 6 months after treatment and before treatment, and ROC was used to evaluate the efficacy of ADC values in predicting complete tissue necrosis after treatment. Results In the 95 lesions, 91 lesions were completely necrotic, and active tissues were found in 4 lesions after treatment. There were statistically significant differences in the ADC values of the lesions at 3 and 6 months after treatment and before treatment (P<0.05),and the ADC values of the tissues after treatment were higher than those before treatment. There was no statistically significant difference in ADC values between 3 and 6 months after treatment and before treatment in normal liver tissue (P>0.05). The area under the ROC of using ADC value to predict the complete necrosis after treatment with cyber knife was 0.767, and the ADC value was 1.23×10‐3 mm2/s as the diagnostic cutoff value. The sensitivity and specificity of the diagnosis were 76.5% and 70.6%, respectively. Conclusion ADC values can distinguish the necrotic component from the active component of hepatocellular carcinoma after treatment, and can be used to evaluate the therapeutic effect of cyber knife in hepatocellular carcinoma.