Comparison of multi-slice spiral CT versus 3.0 T MR imaging in assessing tumor regression after radiofrequency ablation of hepatocellular carcinomas / 中华放射学杂志

ABSTRACT

Objective To assess the diagnostic value of MR imaging in follow-up evaluation of patients with hepatocellular carcinomas ( HCC ) treated with radiofrequency ablation ( RFA ) and to compare it with that of multi-slice CT.Methods From December 2009 to September 2011,there were 48 patients (56 HCCs) treated with RFA after transcatheter arterial chemoembolization (TACE). MR imaging and multi-slice CT were performed for follow-up.Two radiologists independently reviewed these images,detection of residual or recurrent tumor were assessed on a five-point scale and compared with Kappa test and with the method of receiver operating characteristic (ROC) curve analysis.Sensitivity,specificity and accuracy were evaluated.Results The observer agreement rate for MR imaging was higher ( 0.925 ) than for multi-slice CT (0.701,P ＜ 0.05).The area under the ROC curve (AUC)of MR imaging( 0.987 and 0.971 by two radiologists respectively) was significantly higher than that of CT( 0.674 and 0.598 by two radiologists respectively),P ＜0.05. The sensitivity, specificity and accuracy of detection rate for MRI [100％(22/22),95.5％ (86/90) and 95.5％ ( 107/112),respectively] were significantly different with that for multi-slice CT [40.9％ ( 9/22 ),57.8％ ( 52/90 ) and 60.7％ ( 68/112 ),respectively]. Conclusion Diagnostic accuracy and detection rate of residual or recurrent tumor were found to be superior with MR imaging than with multi-slice CT.