Dynamic contrast-enhanced MRI analysis of perfusion changes in advanced hepatocellular carcinoma treated with an antiangiogenic agent: a preliminary study.

Abstract

To evaluate the perfusion changes in advanced hepatocellular carcinoma (HCC) treated with the antiangiogenic agent thalidomide, we used dynamic contrast-enhanced MRI. Dynamic contrast-enhanced MRI was performed before and during thalidomide treatment in seven patients with advanced unresectable HCC that had failed to respond to prior local therapy. A turbo fast low-angle shot sequence was performed in a 1.5-T MR scanner. An operator-defined region of interest was placed in the maximal enhancement region of the tumor site and adjacent tumor-free parenchyma of all patients. A time-intensity curve was plotted and analyzed. The peak enhancement in the first-pass study, the maximal enhancement, and the initial enhancement slope percentage in the first-pass study of the tumor and parenchyma were measured. The changes in these three perfusion parameters were estimated and correlated with clinical outcomes. The seven patients were categorized into two groups on the basis of their clinical outcomes: group A patients were those who had progressive disease, whereas group B patients were those who had stable disease or partial response. Four of the seven patients were classified as group A, and the other three were classified as group B patients. When comparing the MRI parameters for the tumors before and during treatment in group A and group B patients, we found a statistically significant difference for the peak enhancement in the first-pass study, the maximal enhancement, and the enhancement slope percentage in the first-pass study. When comparing the parenchymal parameters, we found a statistically significant difference in the maximal enhancement and borderline significance in the peak enhancement in the first-pass study (p = 0.057) between group A and group B patients. The dynamic MRI parameters showed significant differences between two groups of patients with different clinical outcomes.