Hepatobiliary MRI as novel selection criteria in liver transplantation for hepatocellular carcinoma

Abstract

Background & aims: Hepatobiliary magnetic resonance imaging (MRI) provides additional information beyond the size and number of tumours, and may have prognostic implications. We examined whether pretransplant radiological features on MRI could be used to stratify the risk of tumour recurrence after liver transplantation (LT) for hepatocellular carcinoma (HCC).

Methods: A total of 100 patients who had received a liver transplant and who had undergone preoperative gadoxetic acid-enhanced MRI, including the hepatobiliary phase (HBP), were reviewed for tumour size, number, and morphological type (e.g. nodular, nodular with perinodular extension, or confluent multinodular), satellite nodules, non-smooth tumour margins, peritumoural enhancement in arterial phase, peritumoural hypointensity on HBP, and apparent diffusion coefficients. The primary endpoint was time to recurrence.

Results: In a multivariable adjusted model, the presence of satellite nodules [hazard ratio (HR) 3.07; 95% confidence interval (CI) 1.14-8.24] and peritumoural hypointensity on HBP (HR 4.53; 95% CI 1.52-13.4) were identified as independent factors associated with tumour recurrence. Having either of these radiological findings was associated with a higher tumour recurrence rate (72.5% vs. 15.4% at three years, p <0.001). When patients were stratified according to the Milan criteria, the presence of these two high-risk radiological findings was associated with a higher tumour recurrence rate in both patients transplanted within the Milan criteria (66.7% vs. 11.6% at three years, p <0.001, n = 68) and those who were transplanted outside the Milan criteria (75.5% vs. 28.6% at three years, p <0.001, n = 32).

Conclusions: Radiological features on preoperative hepatobiliary MRI can stratify the risk of tumour recurrence in patients who were transplanted either within or outside the Milan criteria. Therefore, hepatobiliary MRI can be a useful way to select potential candidates for LT.

Lay summary: High-risk radiological findings on preoperative hepatobiliary magnetic resonance imaging (either one of the following features: satellite nodule and peritumoural hypointensity on hepatobiliary phase) were associated with a higher tumour recurrence rate in patients transplanted either within or outside the Milan criteria.

Keywords: Gadoxetic acid; Liver transplantation; Magnetic resonance imaging; Microvascular invasion; Recurrence.