Diffusion-based virtual MR elastography for predicting recurrence of solitary hepatocellular carcinoma after hepatectomy.

Background: To explore the capability of diffusion-based virtual MR elastography (vMRE) in the preoperative prediction of recurrence in hepatocellular carcinoma (HCC) and to investigate the underlying relevant histopathological characteristics.

Methods: Between August 2015 and December 2016, patients underwent preoperative MRI examination with a dedicated DWI sequence (b-values: 200,1500 s/mm) were recruited. The ADC values and diffusion-based virtual shear modulus (μ) of HCCs were calculated and MR morphological features were also analyzed. The Cox proportional hazards model was used to identify the risk factors associated with tumor recurrence. A preoperative radiologic model and postoperative model including pathological features were built to predict tumor recurrence after hepatectomy.

Results: A total of 87 patients with solitary surgically confirmed HCCs were included in this study. Thirty-five patients (40.2%) were found to have tumor recurrence after hepatectomy. The preoperative model included higher μ and corona enhancement, while the postoperative model included higher μ, microvascular invasion, and histologic tumor grade. These factors were identified as significant prognostic factors for recurrence-free survival (RFS) (all p < 0.05). The HCC patients with μ values > 2.325 kPa showed poorer 5-year RFS after hepatectomy than patients with μ values ≤ 2.325 kPa (p < 0.001). Moreover, the higher μ values was correlated with the expression of CK19 (3.95 ± 2.37 vs. 3.15 ± 1.77, p = 0.017) and high Ki-67 labeling index (4.22 ± 1.63 vs. 2.72 ± 2.12, p = 0.001).

Conclusions: The μ values related to the expression of CK19 and Ki-67 labeling index potentially predict RFS after hepatectomy in HCC patients.