Efficiency of regional functional liver volume assessment using Gd-EOB-DTPA-enhanced magnetic resonance imaging for hepatocellular carcinoma with portal vein tumor thrombus

A Novel Method Using Gadolinium-Ethoxybenzyl Diethylenetriamine Pentaacetate Acid-Enhanced Magnetic Resonance Imaging for Predicting Post-Hepatectomy Liver Failure in Hepatocellular Carcinoma Patients with a Major Portal Vein Tumor Thrombus

INTRODUCTION

The usefulness of gadolinium-ethoxybenzyl diethylenetriamine pentaacetate acid-enhanced magnetic resonance imaging (EOB-MRI) in assessing the functional future remnant liver volume (fFRLV) to predict post-hepatectomy liver failure (PHLF) has been previously reported. Herein, we evaluated the efficacy of this technique in patients with hepatocellular carcinoma (HCC) with a major portal vein tumor thrombus (PVTT).

METHODS

This study included 21 patients with PVTT in the ipsilateral first-order branch (Vp3) and 30 patients with PVTT in the main trunk/contralateral branch (Vp4). To evaluate fFRLV, the signal intensity (SI) of the remnant liver was determined on T1-weighted images, using both conventional and newly developed methods. The fFRLV was calculated using the SI of the remnant liver and muscle, remnant liver volume, and body surface area. Preoperative factors predicting PHLF (≥grade B) in HCC patients with Vp3/4 PVTT were evaluated.

RESULTS

In the Vp3 group, we found fFRLV area under the receiver-operating characteristic curves (AUCs) above 0.70 (AUC = 0.875, 0.750) using EOB-MRI results calculated using either the plot or whole method. None of the parameters in the Vp4 group had an AUC greater than 0.70.

CONCLUSION

The fFRLV calculated by EOB-MRI using the whole method can be as useful as the conventional method in predicting PHLF (≥grade B) for HCC patients with Vp3 PVTT.

Evaluation and Prediction of Post-Hepatectomy Liver Failure Using Imaging Techniques: Value of Gadoxetic Acid-Enhanced Magnetic Resonance Imaging

Despite improvements in operative techniques and perioperative care, post-hepatectomy liver failure (PHLF) remains the most serious cause of morbidity and mortality after surgery, and several risk factors have been identified to predict PHLF. Although volumetric assessment using imaging contributes to surgical simulation by estimating the function of future liver remnants in predicting PHLF, liver function is assumed to be homogeneous throughout the liver. The combination of volumetric and functional analyses may be more useful for an accurate evaluation of liver function and prediction of PHLF than only volumetric analysis. Gadoxetic acid is a hepatocyte-specific magnetic resonance (MR) contrast agent that is taken up by hepatocytes via the OATP1 transporter after intravenous administration. Gadoxetic acid-enhanced MR imaging (MRI) offers information regarding both global and regional functions, leading to a more precise evaluation even in cases with heterogeneous liver function. Various indices, including signal intensity-based methods and MR relaxometry, have been proposed for the estimation of liver function and prediction of PHLF using gadoxetic acid-enhanced MRI. Recent developments in MR techniques, including high-resolution hepatobiliary phase images using deep learning image reconstruction and whole-liver T1 map acquisition, have enabled a more detailed and accurate estimation of liver function in gadoxetic acid-enhanced MRI.

Four indices on Gd-EOB-DTPA-enhanced MRI can estimate liver functional reserve compared to ICG-R15: A systematic review and meta-analysis

AIMS

To evaluate the value of four indices of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced (Gd-EOB-DTPA) magnetic resonance as a potential imaging marker of liver functional reserve.

METHODS

PubMed/Medline, Embase, Cochrane Library, and Web of Science were searched for studies concerning the relationship between Gd-EOB-DTPA-enhanced MRI and liver functional reserve estimated by ICG-R15, Pooled correlation coefficient (r) and 95% confidence intervals (CIs) were calculated, Meanwhile, Sensitivity and subgroup analyses were performed along with Egger's test for the estimation of publication bias and potential heterogeneity.

RESULTS

14 publications with 1285 patients were included. The pooled r between relative liver enhancement (RLE), reduction rate of T1 relaxation time of the liver (rrT1), liver-to-spleen ratio (LSR), liver-to-muscle ratio (LMR), and ICG-R15 were -0.49 (95% CI, -0.56 to -0.41, p < 0.05), -0.47 (95% CI, -0.57 to -0.36, p < 0.05), -0.45 (95% CI, -0.55 to -0.34, p < 0.05), -0.50 (95% CI, -0.61 to -0.38, p < 0.05). moderate heterogeneity was observed between studies on rrT1, LSR, LMR, and ICG-R15 (p ≤ 0.05), but no significant heterogeneity was observed between RLE and ICG-R15. Further analysis shows that there was a notable heterogeneity between subgroup analysis of LSR and ICG-R15 stratified by years of publication, as well as rrT1 and LMR stratified by total patients and study design, the distribution funnel plots and the results of Egger's test showed no evidence of publication bias.

CONCLUSIONS

RLE, LSR, LMR, and rrT1 all correlated significantly with ICG-R15-estimated hepatic functional reserve. The four indices represent a promising imaging biomarker in the prediction of liver functional reserve.

Prediction with functional liver volume assessment to achieve the resection limit after portal vein embolization in patients scheduled major hepatectomy

BACKGROUND

Preoperative portal vein embolization (PVE) stimulates liver hypertrophy and improves the safety of major hepatectomy. It is essential to predict the future remnant liver volume (FRLV) and resection limit following PVE. Previously, we reported that evaluating functional FRLV (fFRLV) using EOB-MRI could predict post-hepatectomy liver failure. In this study, we investigated the usefulness of fFRLV in predicting the achieving of adequate resection limit for safe hepatectomy following PVE.

METHODS

We included 55 patients who underwent PVE and were scheduled for major hepatectomy. We calculated the liver-to-muscle ratio in the remnant liver and fFRLV using EOB-MRI. We investigated the pre-PVE variables in determining the nonachievement of the resection limit.

RESULTS

The median observation period between PVE and the first evaluation was 21 days, and the median growth rate of FRLV was 26.4%. In 54.5% of patients, the resection limit of fFRLV (615 mL/m²) was achieved. In logistic regression and receiver-operating characteristic analyses, pre-PVE fFRLV (p < 0.001, area under the curve: 0.852) was the reliable predictor of achieving the resection limit; the cutoff value of pre-PVE fFRLV was 446 mL/m².

CONCLUSION

Pre-PVE fFRLV can be useful in predicting the achievement of adequate resection limit following PVE.

Evaluation of Threshold Dose of Damaged Hepatic Tissue After Carbon-Ion Radiation Therapy Using Gd-EOB-DTPA-Enhanced Magnetic Resonance Imaging

Purpose

To evaluate the threshold dose and associated factors using signal-intensity changes in the irradiated area after carbon-ion radiation therapy (C-ion RT) for patients with liver cancer.

Methods and Materials

Patients treated for the first time with C-ion RT for malignant liver tumors and followed up with 3-Tesla gadoxetic acid (Gd-EOB-DTPA)–enhanced magnetic resonance imaging (MRI) 3 months after treatment completion were retrospectively enrolled. The volume of focal liver reaction (FLR), a low-intensity area in the hepatobiliary phase of Gd-EOB-DTPA after treatment, was measured. Corrected FLR (cFLR) volume, defined as FLR corrected for changes in tumor volume from before to after treatment, was calculated, and the threshold dose was determined by applying the cFLR volume in the dose-volume histogram. To evaluate potential mismatch in fusion images of planning computed tomography and follow-up MRI, the concordance coefficient (CC) was measured, and patients with a CC < 0.7 were excluded. Sixty patients were included. Multiple regression analysis was performed with the threshold dose as the objective variable and the age, dose, number of fractionations, Child-Pugh score, pretreatment liver volume, and pretreatment tumor volume as explanatory variables. The Student t test or Mann-Whitney U test was used as required.

Results

The median threshold doses for each number of dose fractionations (4 fractions, 12 fractions, and overall) were 51.6, 51.9, and 51.8 Gy (relative biological effectiveness [RBE]), respectively, in patients categorized as Child-Pugh class A and 27.0, 28.8, and 27.0 Gy (RBE), respectively, in patients categorized as Child-Pugh class B. In the multiple-regression analysis, only the Child-Pugh score was significant (P < .001). The number of dose fractionations was not statistically significant.

Conclusions

Although few patients in the study had decreased liver function, baseline liver function was the only factor significantly associated with the median threshold dose. These findings facilitate appropriate patient selection to receive C-ion RT for malignant hepatic tumors.

Correlation of liver enhancement in gadoxetic acid-enhanced MRI with liver functions: a multicenter-multivendor analysis of hepatocellular carcinoma patients from SORAMIC trial

OBJECTIVES

To evaluate the correlation between liver enhancement on hepatobiliary phase and liver function parameters in a multicenter, multivendor study.

METHODS

A total of 359 patients who underwent gadoxetic acid-enhanced MRI using a standardized protocol with various scanners within a prospective multicenter phase II trial (SORAMIC) were evaluated. The correlation between liver enhancement on hepatobiliary phase normalized to the spleen (liver-to-spleen ratio, LSR) and biochemical laboratory parameters, clinical findings related to liver functions, liver function grading systems (Child-Pugh and Albumin-Bilirubin [ALBI]), and scanner characteristics were analyzed using uni- and multivariate analyses.

RESULTS

There was a significant positive correlation between LSR and albumin (rho = 0.193; p < 0.001), platelet counts (rho = 0.148; p = 0.004), and sodium (rho = 0.161; p = 0.002); and a negative correlation between LSR and total bilirubin (rho = -0.215; p < 0.001) and AST (rho = -0.191; p < 0.001). Multivariate analysis confirmed independent significance for each of albumin (p = 0.022), total bilirubin (p = 0.045), AST (p = 0.031), platelet counts (p = 0.012), and sodium (p = 0.006). The presence of ascites (1.47 vs. 1.69, p < 0.001) and varices (1.55 vs. 1.69, p = 0.006) was related to significantly lower LSR. Similarly, patients with ALBI grade 1 had significantly higher LSR than patients with grade 2 (1.74 ± 0.447 vs. 1.56 ± 0.408, p < 0.001); and Child-Pugh A patients had a significantly higher LSR than Child-Pugh B (1.67 ± 0.44 vs. 1.49 ± 0.33, p = 0.021). Also, LSR was negatively correlated with MELD-Na scores (rho = -0.137; p = 0.013). However, one scanner brand was significantly associated with lower LSR (p < 0.001).

CONCLUSIONS

The liver enhancement on the hepatobiliary phase of gadoxetic acid-enhanced MRI is correlated with biomarkers of liver functions in a multicenter cohort. However, this correlation shows variations between scanner brands.

KEY POINTS

• The correlation between liver enhancement on the hepatobiliary phase of gadoxetic acid-enhanced MRI and liver function is consistent in a multicenter-multivendor cohort. • Signal intensity-based indices (liver-to-spleen ratio) can be used as an imaging biomarker of liver function. • However, absolute values might change between vendors.

Volumetric assessment and clinical predictors of cirrhosis in patients undergoing hepatectomy for hepatocellular carcinoma with presumed normal liver function

AIM

Indocyanine green retention rate at 15 min (ICGR15) is a frequently used indicator of liver function. Herein, clinicopathological characteristics of cirrhotic patients with normal ICGR15 value (< 10%) were investigated, as these patients have risk of postoperative liver insufficiency when receiving a major hepatic resection.

METHODS

Patients undergoing hepatectomy for hepatocellular carcinoma were divided into three groups: non-cirrhotic livers (Group A, n = 112): cirrhotic livers with ICGR15 < 10% (Group B, n = 71): and cirrhotic livers with ICGR15 > 10% (Group C, n = 296). Background characteristics and surgical outcomes were compared between groups. Functional liver volume (FLV) was computed using total liver volume and signal intensity ratio. Liver parenchymal cell volume ratio was measured in non-cancerous tissue obtained from resected specimens. Univariate and multivariate analyses were performed to detect clinical characteristics correlating with cirrhotic liver pathology with normal ICGR15.

RESULTS

There was no significant difference between groups in TLV. FLV was gradually reduced from Group A toward Group C. Liver parenchymal cell volume ratio was also gradually reduced from Group A toward Group C. Multivariate analysis revealed that platelet count (< 12 × 10⁴/mm³) (p = 0.001) and prothrombin time (< 80%) (p = 0.025) were significantly associated with cirrhotic liver pathology among patients with normal ICGR15.

CONCLUSION

Our results suggested that cirrhotic liver pathology despite normal liver function was characterized by slightly decreasing liver parenchyma as well as slight degree of fibrosis. Platelet count and PT% are useful for predicting liver cirrhosis with normal ICGR15.