4:12 PMAbstract No. 77 - Does lesion enhancement pattern correlate between baseline MR and follow-up CT in patients with hepatocellular carcinoma (HCC) treated using conventional transarterial chemoembolization (cTACE)? A quantitative, multi-modality analysis

Purpose

An indicator of successful Lipiodol deposition is the matching of enhancement patterns on follow-up CT with baseline MR. To date, this comparison has largely been done on a qualitative basis. Recent quantitative approaches measure enhancement regionally, losing spatial localization. Our study measures the enhancement patterns observed inside targeted HCC lesions and correlates them on a voxel-wise basis between baseline multi-phasic MR, where enhancement is indicative of viable tumor, and

Materials

In our retrospective single center study, 20 patients with a total of 27 HCC lesions (who received conventional TACE in 2014 and 2015) were included. Each patient underwent multi-phasic MR imaging within 4 weeks prior to TACE, and CT imaging 24 hours afterwards. The MR and CT images corresponding to each patient were registered with the transformation generated by the robust point matching algorithm (BioImage Suite, Yale School of Medicine, New Haven, CT) which optimally aligned the liver

Results

For each lesion, the fraction of tumor voxels which exhibited consistent inter-modality enhancement showed positive correlation with the DSC. Linear regression analysis demonstrated a statistically significant (p = 0.003) positive correlation between these quantities (slope = 0.57 ± 0.17). Well registered tumors (DSC>0.8) contained a majority (average=70.8%) of voxels which individually showed a consistent enhancement behavior on both MR and CT imaging.

Conclusions

We showed that baseline enhancement on MR as measured by voxel-wise analysis correlates with Lipiodol deposition on follow-up CT. This can enable a 3D quantitative approach to predict tumor response and drug uptake.

References

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