High-risk nodules detected in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MR imaging in cirrhosis or chronic hepatitis: incidence and predictive factors for hypervascular transformation, preliminary results.

PURPOSE

To evaluate the incidence and predictive factors of hypervascular transformation during follow-up of "high-risk nodules" detected in the hepatobiliary phase of initial Gd-EOB-DTPA-enhanced MRI in chronic liver disease patients.

MATERIALS AND METHODS

A total of 109 patients with chronic liver disease who underwent Gd-EOB-DTPA-enhanced MRI several times were investigated. Of these, 43 patients had 76 high-risk nodules with both hypointensity in the hepatobiliary phase and hypovascularity in the arterial phase of initial MRI. These nodules were observed until hypervascularity was detected. MRI and clinical findings were compared to assess the incidence and potential predictive factors for hypervascular transformation between the group showing hypervascular transformation and the group not showing hypervascularization.

RESULTS

The median observation period was 242.5 ± 203.2 days (range, 47-802 days). Overall, 24 of 76 high-risk nodules (31.6%) showed hypervascular transformation during follow-up (median observation period, 186.0 ± 190.3 days). The growth rate of the nodules (P < 0.001), the presence of fat within nodules (P = 0.037), and hyperintensity on T1-weighted images (P = 0.018) were significantly correlated with hypervascularization.

CONCLUSION

Subsets of high-risk nodules tended to show hypervascular transformation during follow-up, with an increased growth rate, the presence of fat, and hyperintensity on T1-weighted images as predictive factors.