Liver Transplantation Criteria for Hepatocellular Carcinoma, Including Posttransplant Management

The effectiveness of exercise prehabilitation on aerobic capacity, muscle strength and body composition in patients with cirrhosis awaiting liver transplantation: a systematic review and meta-analysis protocol

INTRODUCTION

Cirrhosis is the main cause of morbidity and mortality globally, accounting for approximately 1.2 million deaths annually. Impaired aerobic capacity, muscle wasting and reduced muscle strength are significant complications in patients with cirrhosis. Preoperative exercise intervention "prehabilitation" has been recognised as a potential approach to optimise muscle strength, aerobic capacity and body composition as well as quality of life in patients awaiting abdominal surgery. However, there is little evidence on the effects of preoperative exercise on older adults with cirrhosis and awaiting liver transplant. Thus, the primary objective of this systematic review and meta-analysis will be to assess the effects of exercise interventions in improving aerobic capacity, muscle strength and body composition of older adults with cirrhosis and awaiting liver transplant.

METHODS AND ANALYSIS

This systematic review and metaanalysis protocol was designed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This systematic review will include all peer-reviewed randomised controlled trials (RCTs), including cluster RCTs, controlled (non-controlled), complex clinical trials (CCTs) or cluster trials, cohort, observational studies published in English from inception until July 2024. The following electronic databases will be searched: MEDLINE (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL (EBSCO) and Scopus (Elsevier) and supplemented by a secondary screening of the reference lists of all included articles. Searches will involve studies with both male and female participants aged ≥ 18 years with cirrhosis and awaiting liver transplant. Primary outcomes will include muscle strength, and aerobic capacity. The secondary outcomes include body composition (e.g. body mass index, and thigh circumference). The Cochrane Collaboration Risk of Bias Tool will be used to evaluate quality of the studies and Review Manager (RevMan) V.5.3 (Copenhagen, Denmark: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Effect sizes will be expressed as a standardised mean difference, and their 95% confidence intervals will be calculated and presented as a forest plot. The standard χ2 and I2 tests will be used to test heterogeneity.

CONCLUSION

This systematic review and meta-analysis is anticipated to provide meaningful and contemporary evidence on the effects of preoperative exercise in older adults living with cirrhosis and awaiting liver transplant. In addition, the findings will help clinicians with developing safe and effective preoperative exercise regimens for these patients.

Validation of Japanese indication criteria for deceased donor liver transplantation for hepatocellular carcinoma: Analysis of US national registry data

AIM

The Japanese indication criteria for liver transplantation (LT) for hepatocellular carcinoma (HCC) have been updated based on living donor LT data to include either the Milan criteria (MC) or the 5-5-500 rule, which requires a nodule size of ≤5 cm, ≤5 nodules, and an alpha-fetoprotein (AFP) level ≤500 ng/mL. We aimed to validate the 5-5-500 rule and the MC for deceased donor LT (DDLT).

METHODS

Using national registry data from the United States from 2010 to 2014, we separated DDLT patients into four groups based on the MC and the 5-5-500 rule. The AFP values were stratified into categories: ≤100, 101-300, 301-500, and >500 ng/mL.

RESULTS

The 5-year survival rate was significantly lower for patients in the groups within MC/beyond 5-5-500 (56.3%) or beyond MC/5-5-500 (60.7%) than for patients in the groups within MC/5-5-500 (76.2%) and beyond MC/within 5-5-500 (72.3%) (p < 0.01). Hepatocellular carcinoma recurrence at 5 years was highest for the within MC/beyond 5-5-500 (25.4%) group, followed by the beyond MC/within 5-5-500 (13.1%), beyond MC/5-5-500 (9.6%), and within MC/5-5-500 (7.4%) groups. The stratified 5-year survival rates after DDLT were 76.5%, 72.4%, 58.4%, and 55.6% in the AFP ≤100, 101-300, 301-500, and >500 categories, respectively (p < 0.01).

CONCLUSION

The 5-5-500 rule guides the appropriate selection of patients with HCC for DDLT. Patients with AFP levels from 300 to 500 ng/mL had inferior outcomes even when they met the 5-5-500 rule, so further investigation is needed to guide their treatment.

Automated liver volumetry and hepatic steatosis quantification with magnetic resonance imaging proton density fat fraction

BACKGROUND

Preoperative imaging evaluation of liver volume and hepatic steatosis for the donor affects transplantation outcomes. However, computed tomography (CT) for liver volumetry and magnetic resonance spectroscopy (MRS) for hepatic steatosis are time consuming. Therefore, we investigated the correlation of automated 3D-multi-echo-Dixon sequence magnetic resonance imaging (ME-Dixon MRI) and its derived proton density fat fraction (MRI-PDFF) with CT liver volumetry and MRS hepatic steatosis measurements in living liver donors.

METHODS

This retrospective cross-sectional study was conducted from December 2017 to November 2022. We enrolled donors who received a dynamic CT scan and an MRI exam within 2 days. First, the CT volumetry was processed semiautomatically using commercial software, and ME-Dixon MRI volumetry was automatically measured using an embedded sequence. Next, the signal intensity of MRI-PDFF volumetric data was correlated with MRS as the gold standard.

RESULTS

We included the 165 living donors. The total liver volume of ME-Dixon MRI was significantly correlated with CT (r = 0.913, p < 0.001). The fat percentage measured using MRI-PDFF revealed a strong correlation between automatic segmental volume and MRS (r = 0.705, p < 0.001). Furthermore, the hepatic steatosis group (MRS ≥5%) had a strong correlation than the non-hepatic steatosis group (MRS <5%) in both volumetric (r = 0.906 vs. r = 0.887) and fat fraction analysis (r = 0.779 vs. r = 0.338).

CONCLUSION

Automated ME-Dixon MRI liver volumetry and MRI-PDFF were strongly correlated with CT liver volumetry and MRS hepatic steatosis measurements, especially in donors with hepatic steatosis.

[Liver transplantation for treatment of nonresectable primary and secondary liver malignancies : Hepatocellular and cholangiocellular carcinomas and colorectal liver metastases]

BACKGROUND

With the increasing efficacy of systemic therapy, liver transplantation plays an important role not only for hepatocellular carcinoma (HCC) but also for nonresectable intrahepatic cholangiocellular carcinoma (iCC), perihilar cholangiocellular carcinoma (phCC) and colorectal liver metastases (CRLM).

AIM

To review the current state of knowledge regarding the indications, patient selection and expected outcomes of liver transplantation for HCC, iCC, phCC and CRLM.

RESULTS

When combined with neoadjuvant locoregional therapy (LRT) and/or systemic therapy, patients with nonresectable HCC, iCC, pCC and CRLM confined to the liver can be successfully transplanted with 5‑year survival rates exceeding 65%. The key to success is strict patient selection, which includes oncogenetic (e.g., BRAFV600E mutation status) and clinical criteria indicative of individual tumor biology (tumor markers: alpha-fetoprotein, AFP/carbohydrate antigen 19‑9, CA19-9/carcinoembryonic antigen, CEA, stable response to neoadjuvant therapy) in addition to morphometric criteria.

CONCLUSION

Liver transplantation offers the possibility of curative treatment even for nonresectable hepatic malignancies. A major limitation of this treatment is the lack of donor organs. Crucial for success is patient selection based on individual tumor biology.

Analytical validation and algorithm improvement of HepatoPredict kit to assess hepatocellular carcinoma prognosis before a liver transplantation

Objectives

To verify the analytical performance of the HepatoPredict kit, a novel tool developed to stratify Hepatocellular Carcinoma (HCC) patients according to their risk of relapse after a Liver Transplantation (LT).

Methods

The HepatoPredict tool combines clinical variables and a gene expression signature in an ensemble of machine-learning algorithms to forecast the benefit of a LT in HCC patients. To ensure the accuracy and reliability of this method, extensive analytical validation was conducted to verify its specificity and robustness. The experiments were designed following the guidelines for multi-target genomic assays such as ISO201395-2019, MIQE, CLSI-MM16, CLSI-MM17, and CLSI-EP17-A. The validation process included reproducibility between operators and between RNA extractions and RT-qPCR runs, and interference of input RNA levels or varying reagent levels. A recently retrained version of the HepatoPredict algorithms was also tested.

Results

The validation process demonstrated that the HepatoPredict kit met the required standards for robustness (p > 0.05), analytical specificity (inclusivity of 95 %), and sensitivity (LoB, LoD, linear range, and amplification efficiency between 90 and 110 %). The operator, equipment, input RNA, and reagents used had no significant effect on the HepatoPredict results. Additionally, the testing of a recently retrained version of the HepatoPredict algorithm, showed that this new version further improved the accuracy of the kit and performed better than existing clinical criteria in accurately identifying HCC patients who are more likely to benefit LT.

Conclusions

Even with the introduced variations in molecular and clinical variables, the HepatoPredict kit's prognostic information remains consistent. It can accurately identify HCC patients who are more likely to benefit from a LT. Its robust performance also confirms that it can be easily integrated into standard diagnostic laboratories.

Expanding the Boundaries for Liver Transplantation for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, which was the third most common cause of cancer death worldwide in 2020. Transplantation remains the preferred treatment for cure in otherwise unresectable HCC. There are several areas of active research that have led to expansion of eligibility criteria for transplantation including local-regional therapy for downstaging patients presenting outside of the Milan criteria and identification of tumor biomarkers aiding in the early diagnosis, determining prognosis and likelihood of recurrence after transplantation for HCC. New neoadjuvant therapies and post-transplant immunosuppression regimens may also result in expansion of transplant eligibility criteria for HCC.

Downstaging Techniques for Hepatocellular Carcinoma in Candidates Awaiting Liver Transplantation

During the last decade, downstaging for hepatocellular carcinoma has expanded the pool of patients eligible for liver transplantation. The literature is rife with attempts to elucidate best treatment strategies with novel locoregional and systemic therapies continuing to emerge. Several trials have confirmed the large-scale success of downstaging protocols, with equitable long-term survival and recurrence rates after liver transplant. We review the currently available techniques used for downstaging, including their indications, complications, and efficacies. New frontiers have focused on the potential role of immunotherapy in the neoadjuvant setting, although more research is needed to delineate its role in current treatment paradigms.

Downstaging Hepatocellular Carcinoma before Transplantation: Role of Immunotherapy Versus Locoregional Approaches

Hepatocellular carcinoma (HCC) continues to be a leading cause of cancer-related death in the United States. With advances in locoregional therapy for unresectable HCC during the last 2 decades and the recent expansion of transplant criteria for HCC, as well as ongoing organ shortages, patients are spending more time on the waitlist, which has resulted in an increased usage of locoregional therapies. The plethora of molecularly targeted therapies and immune checkpoint inhibitors under investigation represent the new horizon of treatment of HCC not only in advanced stages but also potentially at every stage of diagnosis and management.

Effects of CYP3A5 Genotypes on Thrombocytopenia in Liver Transplantation Patients Treated with Tacrolimus

BACKGROUND

Thrombocytopenia is a complication after liver transplantation. This study's aims were to evaluate the role of CYP3A5 genotypes on tacrolimus-induced thrombocytopenia after orthotopic liver transplantation.

METHODS

In this retrospective case-control study, data from 100 patients who underwent deceased-donor liver transplantation (DDLT) were divided into CYP3A5*3 genotype (donor/recipient) tacrolimus fast- (A*/A*, n = 22), intermediate- (A*/GG, n = 20; GG/A*, n = 31) and slow-metabolizer (GG/GG, n = 27) groups. Platelet count changes and prognosis for 180 days after surgery were compared.

RESULTS

Platelet counts declined significantly after DDLT, especially on postoperative day (POD) 3, and continued at low levels for a week thereafter in all groups. In the GG/GG group, platelet counts on POD3 (50.29 ± 5.44 × 109/L) were the lowest among the groups (A*/A*, 71.00 ± 6.22 × 109/L; A*/GG, 57.95 ± 6.21 × 109/L; GG/A*, 75.90 ± 5.56 × 109/L) (p = 0.006). Compared with the A*/A* genotype, tacrolimus nadir levels were significantly higher in GG/GG genotype patients, who also exhibited a higher incidence of hemorrhage (22.2%, p = 0.011). A combination of a nadir blood concentration of tacrolimus ≥ 4.74 ng/mL and spleen size ≥ 165.5 mm was a risk factor for increased thrombocytopenia after DDLT on POD3, with an AUC of 0.735 (sensitivity, 77.2%; specificity, 41.7%).

CONCLUSIONS

A high blood concentration of tacrolimus after the early stage of DDLT is a major risk factor for hemorrhage. For the CYP3A5 genotype (GG/GG), controlling the blood concentration of tacrolimus below the target concentration until POD3 can avoid thrombocytopenia-related complications.

Racial Disparities in Liver Transplantation for Hepatocellular Carcinoma in the United States: An Update

BACKGROUND

Previous studies have demonstrated a disparity in liver transplantation (LT) for hepatocellular carcinoma (HCC) among races in the United States (U.S.).

AIMS

We aimed to update the literature on the odds, trends, and complications of LT in the treatment of hepatocellular carcinoma (HCC), among individuals of different racial backgrounds.

METHODS

This is a nationwide study of adult individuals admitted for LT with a primary diagnosis of HCC. Using weighted data from the National Inpatient Sample (NIS) database, we compared the odds of LT among different races from 2016 to 2020, using a multivariate regression analysis. We further assessed the trends and outcomes of LT among races.

RESULTS

A total of 112,110 adult were hospitalized with a primary diagnosis of HCC. 3020 underwent LT. When compared to Whites, the likelihood of undergoing LT for HCC was significantly reduced in Blacks (OR = 0.60, 95% CI = 0.46-0.78). Further, Blacks had increased mortality rates (7% in Blacks vs. 1% in Whites, p < 0.001), sepsis (11% in Blacks vs. 3% in Whites, p = 0.015), and acute kidney injury (AKI) (54% in Blacks vs. 31% in Whites, p < 0.001) following LT.

CONCLUSIONS

Individuals identifying as Blacks were less likely to undergo LT for HCC, and more likely to develop complications. Further initiatives are warranted to mitigate the existing disparities among racial groups.

Immunotherapy and Liver Transplantation: A Narrative Review of Basic and Clinical Data

Immune checkpoint inhibitors (ICIs) have improved the management of patients with intermediate- and advanced-stage HCC, even making some of them potential candidates for liver transplantation. However, acute rejection has been observed after ICI therapy, challenging its safety in transplant settings. We summarize the key basic impact of immune checkpoints on HCC and liver transplantation. We analyze the available case reports and case series on the use of ICI therapy prior to and after liver transplantation. A three-month washout period is desirable between ICI therapy and liver transplantation to reduce the risk of acute rejection. Whenever possible, ICIs should be avoided after liver transplantation, and especially so early after a transplant. Globally, more robust prospective data in the field are required.

Liver Transplantation: Protocol for Recipient Selection, Evaluation, and Assessment

Liver transplantation (LT) is the definitive therapy for patients with end-stage liver disease, acute liver failure, acute-on-chronic liver failure, hepatocellular carcinoma, and metabolic liver diseases. The acceptance of LT in Asia has been gradually increasing and so is the expertise to perform LT. Preparing a patient with cirrhosis for LT is the most important aspect of a successful LT. The preparation for LT begins with the first index decompensation for a patient with cirrhosis. Patients planned for LT should undergo a thorough screening for infections, and a complete cardiac, pulmonology, and psychosocial evaluation pre-LT. In this review, we discuss the indications and contraindications of LT and the evaluation and assessment of patients with liver disease planned for LT.

Nonalcoholic fatty liver disease and hepatocellular carcinoma:Insights in epidemiology, pathogenesis, imaging, prevention and therapy

Hepatocellular carcinoma (HCC) is estimated to be the third leading cause of cancer-related mortality and is characterized by low survival rates. Nonalcoholic fatty liver disease (NAFLD) is emerging as a leading cause of HCC, whose rates are increasing, owing to the increasing prevalence of NAFLD. The pathogenesis of NAFLD-associated HCC is multifactorial: insulin resistance, obesity, diabetes and the low-grade hepatic inflammation, which characterizes NAFLD, seem to play key roles in the development and progression of HCC. The diagnosis of NAFLD-associated HCC is based on imaging in the presence of liver cirrhosis, preferably computerized tomography or magnetic resonance imaging, but liver biopsy for histological confirmation is usually required in the absence of liver cirrhosis. Some preventive measures have been recommended for NAFLD-associated HCC, including weight loss, cessation of even moderate alcohol drinking and smoking, as well as the use of metformin, statins and aspirin. However, these preventive measures are mainly based on observational studies, thus they need validation in trials of different design before introducing in clinical practice. The treatment of NAFLD should be tailored on an individual basis and should be ideally determined by a multidisciplinary team. In the last two decades, new medications, including tyrosine kinase inhibitors and immune checkpoints inhibitors, have improved the survival of patients with advanced HCC, but trials specifically designed for patients with NAFLD-associated HCC are scarce. The aim of this review was to overview evidence on the epidemiology and pathophysiology of NAFLD-associated HCC, then to comment on imaging tools for its appropriate screening and diagnosis, and finally to critically summarize the currently available options for its prevention and treatment.

Outcome of split liver transplantation vs living donor liver transplantation: A systematic review and meta-analysis

BACKGROUND

The outcomes of liver transplantation (LT) from different grafts have been studied individually and in combination, but the reports were conflicting with some researchers finding no difference in both short-term and long-term outcomes between the deceased donor split LT (DD-SLT) and living donor LT (LDLT).

AIM

To compare the outcomes of DD-SLT and LDLT we performed this systematic review and meta-analysis.

METHODS

This systematic review was performed in compliance with the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. The following databases were searched for articles comparing outcomes of DD-SLT and LDLT: PubMed; Google Scholar; Embase; Cochrane Central Register of Controlled Trials; the Cochrane Database of Systematic Reviews; and Reference Citation Analysis (https://www.referencecitationanalysis.com/). The search terms used were: "liver transplantation;" "liver transplant;" "split liver transplant;" "living donor liver transplant;" "partial liver transplant;" "partial liver graft;" "ex vivo splitting;" and "in vivo splitting."

RESULTS

Ten studies were included for the data synthesis and meta-analysis. There were a total of 4836 patients. The overall survival rate at 1 year, 3 years and 5 years was superior in patients that received LDLT compared to DD-SLT. At 1 year, the hazard ratios was 1.44 (95% confidence interval: 1.16-1.78; P = 0.001). The graft survival rate at 3 years and 5 years was superior in the LDLT group (3 year hazard ratio: 1.28; 95% confidence interval: 1.01-1.63; P = 0.04).

CONCLUSION

This meta-analysis showed that LDLT has better graft survival and overall survival when compared to DD-SLT.

First-Line Targeted Therapy for Hepatocellular Carcinoma: Role of Atezolizumab/Bevacizumab Combination

Hepatocellular carcinoma (HCC) is an aggressive malignancy accounting for 90% of primary liver malignancies. Therapeutic options for HCC are primarily based on the baseline functional status, the extent of disease at presentation and the underlying liver function that is clinically evaluated by the Barcelona-Clinic Liver Cancer system and Child−Pugh score. In patients with advanced HCC, the United States Food and Drug Administration (US-FDA) approved systemic therapies include the combination of atezolizumab−bevacizumab, sorafenib, and lenvatinib in the first line setting while cabozantinib, regorafenib, ramucirumab (in patients with alfa-fetoprotein [AFP] > 400 ng/mL), pembrolizumab, nivolumab, and nivolumab-ipilimumab combination are reserved for patients who progressed on sorafenib. European Medical Agency (EMA) approved the use of atezolizumab−bevacizumab, sorafenib, and lenvatinib in the first line setting, while cabozantinib, regorafenib, and ramucirumab (in patients with alfa-fetoprotein [AFP] > 400 ng/mL) are approved for use in patients that progressed on first-line therapy. In the first line setting, sorafenib demonstrated a median overall survival (OS) benefit of 3 months as compared to that of best supportive care in randomized phase III trials, while lenvatinib was shown to be non-inferior to sorafenib. Recently, phase 3 studies with immunotherapeutic agents including atezolizumab plus a bevacizumab combination and tremelimumab plus durvalumab combination demonstrated a better OS and progression free survival (PFS) compared to sorafenib in the first-line setting, making them attractive first-line options in advanced HCC. In this review, we outlined the tumorigenesis and immune landscape of HCC in brief and discussed the role and rationale of combining immunotherapy and anti-VEGF therapy. We further expanded on potential limitations and the future directions of immunotherapy in combination with targeted agents in the management of advanced HCC.