Hepatobiliary versus Extracellular MRI Contrast Agents in Hepatocellular Carcinoma Detection: Hepatobiliary Phase Features in Relation to Disease-free Survival.

Background MRI with hepatobiliary contrast material is more sensitive than MRI with extracellular contrast material in the detection of hepatocellular carcinoma (HCC). Purpose To determine whether postsurgical outcomes differ between patients who undergo MRI with hepatobiliary contrast material and those who undergo MRI with extracellular contrast material by analyzing disease-free survival (DFS) rates after curative resection of HCC. Materials and Methods From January 2014 to December 2015, 170 treatment-naïve patients who underwent contrast-enhanced preoperative liver MRI and curative hepatic resection for HCC were retrospectively included and observed until September 2018. DFS rates were compared between the two groups, which were classified based on the type of MRI contrast agent used. The MRI with hepatobiliary contrast material group was further divided into a hypointense nodule-positive group and a hypointense nodule-negative group according to the presence of residual hepatobiliary phase (HBP) hypointense nodules without arterial phase hyperenhancement (APHE) after surgery. DFS rates were calculated by using the Kaplan-Meier method and were compared among the three groups by using a log-rank test. Results Patients were included in either the MRI with extracellular contrast material group (n = 53; mean age, 60 years ± 9 [standard deviation]) or the hepatobiliary contrast material group (n = 117; mean age, 60 years ± 8; 26 patients were in the hypointense nodule-positive group). Over a median follow-up period of 34.1 months, median DFS rates did not differ between the extracellular contrast material group (35.8 months) and the hepatobiliary contrast material group (43.5 months) (P = .46). However, median DFS in the extracellular contrast material group was longer than that in the hypointense nodule-positive group (35.8 months vs 25.8 months, P < .001) and shorter than that in the hypointense nodule-negative group (35.8 months vs 48.6 months, P = .02). Conclusion Patients who undergo preoperative MRI with hepatobiliary contrast material and resection of hepatobiliary phase hypointense nodules without arterial phase hyperenhancement may show better disease-free survival. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Motosugi in this issue.