Serum Tumor Markers Provide Refined Prognostication in Selecting Liver Transplantation Candidate for Hepatocellular Carcinoma Patients Beyond the Milan Criteria. Ann Surg. 2016;263:842-850. [PMID: 26779979 DOI: 10.1097/sla.0000000000001578]

Role of protein induced by vitamin-K absence-II in transplanted patients with HCC not producing alpha-fetoprotein

Elevated Protein Induced by Vitamin-K Absence-II (PIVKA-II) has been shown to be an adverse prognostic factor in HCC patients undergoing liver transplantation (LT). No definitive data are available about the impact of PIVKA-II concerning post-LT recurrence in patients not secreting (≤ 20 ng/mL) alpha-fetoprotein (AFP). An observational retrospective study of the East-West HCC-LT consortium is reported. Between 2000 and 2019, 639 HCC patients were enrolled in 5 collaborative European and Japanese centers. To minimize the initial selection bias, an inverse probability therapy weighting method was adopted to analyze the data. In the post-inverse probability therapy weighting population, PIVKA-II (HR = 2.00; 95% CI: 1.52-2.64; p < 0.001) and AFP (HR=1.82; 95% CI: 1.48-2.24; p < 0.001) were the most relevant independent risk factors for post-LT recurrence. A sub-analysis focusing only on patients who are AFP non-secreting confirmed the negative role of PIVKA-II (HR=2.06, 95% CI: 1.26-3.35; p =0.004). When categorizing the entire population into 4 groups according to the AFP levels (≤ or > 20 ng/mL) and PIVKA (≤ or > 300 mUA/mL) at the time of LT, the lowest recurrence rates were observed in the low AFP-PIVKA-II group (5-year recurrence rate = 8.0%). Conversely, the high AFP-PIVKA-II group had the worst outcome (5-year recurrence rate = 35.1%). PIVKA-II secretion is a relevant risk factor for post-LT HCC recurrence. The role of this marker is independent of the AFP status. Combining both tumor markers, especially in the setting of LT, should be of great relevance for adding information about predicting the post-LT risk of tumor recurrence and selecting these patients for transplantation.

Merits and boundaries of the BCLC staging and treatment algorithm: Learning from the past to improve the future with a novel proposal

In this Expert Opinion, we thoroughly analyse the Barcelona Clinic Liver Cancer (BCLC) staging and treatment algorithm for hepatocellular carcinoma (HCC) that, since 1999, has standardised HCC management, offering a structured approach for the prognostic evaluation and treatment of patients with HCC. The first part of the article presents the strengths and evolutionary improvements of the BCLC staging system. Nevertheless, both patient characteristics and available treatments have changed in the last two decades, limiting the role of the BCLC criteria for treatment allocation in a growing number of patients. As therapeutic options expand and become more effective, the stage-linked treatment decision-making algorithm may lead to undertreatment and suboptimal outcomes for patients with disease beyond early-stage HCC. Consequently, strict adherence to BCLC criteria is limited in expert centres, particularly for patients diagnosed beyond early-stage HCC. Although the BCLC system remains the benchmark against which other therapeutic frameworks must be judged, the era of precision medicine calls for patient-tailored therapeutic decision-making (by a multidisciplinary tumour board) rather than stage-dictated treatment allocation. Acknowledging this conceptual difference in clinical management, the second part of the article describes a novel "multiparametric therapeutic hierarchy", which integrates a comprehensive assessment of clinical factors, biomarkers, technical feasibility, and resource availability. Lastly, considering the increasing efficacy of locoregional and systemic treatments, the concept of "converse therapeutic hierarchy" is introduced. These treatments can increase the feasibility (conversion approach) and effectiveness (adjuvant approach of systemic therapy) of potentially curative approaches to greatly improve clinical outcomes.

Pure laparoscopic donor hepatectomy: Experience of 556 cases at Seoul National University Hospital

Pure laparoscopic donor hepatectomy (PLDH) has become a routine procedure at Seoul National University Hospital, and the pure laparoscopic method is now being applied to liver recipients as well. This study aimed to review the procedure and outcomes of PLDH to identify any areas that required improvement. Data from 556 donors who underwent PLDH between November 2015 and December 2021 and their recipients were retrospectively reviewed. Among these, 541 patients underwent pure laparoscopic donor right hepatectomy (PLDRH). The mean hospital stay of the donor was 7.2 days, and the rate of grade I, II, IIIa, and IIIb complications was 2.2%, 2.7%, 1.3%, and 0.9%, respectively, without any irreversible disabilities or mortalities. The most common early and late major complications in the recipient were intraabdominal bleeding (n = 47, 8.5%) and biliary problems (n = 198, 35.6%), respectively. Analysis of the PLDRH procedure showed that operative time, liver removal time, warm ischemic time, Δhemoglobin%, Δtotal bilirubin%, and postoperative hospital stay decreased significantly as the number of cases accumulated. In conclusion, the operative outcomes of PLDRH improved as the number of cases increased. However, continuous caution is needed because major complications still occur in donors and recipients even after hundreds of cases.

Liver Transplant as a Treatment of Primary and Secondary Liver Neoplasms

Importance

Liver malignancies are an increasing global health concern with a high mortality. We review outcomes following liver transplant for primary and secondary hepatic malignancies.

Observations

Transplant may be a suitable treatment option for primary and secondary hepatic malignancies in well-selected patient populations.

Conclusions and Relevance

Many patients with primary or secondary liver tumors are not eligible for liver resection because of advanced underlying liver disease or high tumor burden, precluding complete tumor clearance. Although liver transplant has been a long-standing treatment modality for patients with hepatocellular carcinoma, recently transplant has been considered for patients with other malignant diagnoses. In particular, while well-established for hepatocellular carcinoma and select patients with perihilar cholangiocarcinoma, transplant has been increasingly used to treat patients with intrahepatic cholangiocarcinoma, as well as metastatic disease from colorectal liver and neuroendocrine primary tumors. Because of the limited availability of grafts and the number of patients on the waiting list, optimal selection criteria must be further defined. The ethics of organ allocation to individuals who may benefit from prolonged survival after transplant yet have a high incidence of recurrence, as well as the role of living donation, need to be further discerned in the setting of transplant oncology.

Liver Transplantation for Hepatocellular Carcinoma: A Narrative Review and A Glimpse into The Future

Liver transplantation (LT) is a highly effective treatment for carefully selected patients with hepatocellular carcinoma (HCC). In this review, we explored the development of LT selection criteria and organ allocation policies, comparing original data to underscore their historical progression into the intricate task of quantitatively estimating pre- and post-LT survivals. We emphasized the role of biomarkers such as serum alpha-fetoprotein, Des-gamma-carboxy-prothrombin, circulating tumor cells, and circulating tumor DNA in predicting patient outcomes. Additionally, we examined the transplant-associated survival benefits and the difficulties in accurately calculating these benefits. We also reviewed recent advancements in targeted therapy and checkpoint inhibitors for advanced, inoperable HCC and projected their integration into LT for HCC. We further discussed the growing use of living donor liver transplants in the United States and compared its outcomes with those of deceased donor liver transplants. Furthermore, we examined the progress in machine perfusion techniques, which have shown potential in improving patient outcomes and enlarging the donor pool. These advancements present opportunities to enhance LT patient survivals, refine selection criteria, establish new priority metrics, develop innovative bridging and downstaging strategies, and formulate redesigned LT strategies for HCC treatments.

Optimal Liver Transplantation Criteria for Hepatocellular Carcinoma

Liver transplantation continues to be the optimal treatment for hepatocellular carcinoma (HCC). Given the limited organ supply, patient selection for liver transplant must carefully balance tumor progression with risk of recurrence posttransplant. There are several pretransplant selection criteria that incorporate biomarkers as well as imaging modality to risk-stratify patients as we continue to look for the optimal transplant cutoff for patients with HCC, which should be transplant-center specific, and account for organ availability and dynamic response to locoregional therapy.

Incorporation of protein induced by vitamin K absence or antagonist-II into transplant criteria expands beneficiaries of liver transplantation for hepatocellular carcinoma: a multicenter retrospective cohort study in China

INTRODUCTION

In order to maximize the utilization of precious donor liver, precisely determining potential hepatocellular carcinoma (HCC) candidates who will benefit from liver transplantation (LT) is essential. As a crucial diagnostic biomarker for HCC, protein induced by vitamin K absence or antagonist-II (PIVKA-II) has become one of the key indicators for assessing tumor recurrence risk after LT. This study aims to investigate the role of PIVKA-II in recipient selection and prognostic stratification.

METHODS

The clinicopathologic data of HCC patients undergoing LT from 2015 to 2020 in six Chinese transplant centers were collected. Univariate and multivariate analyses were performed to determine risk factors for disease free survival (DFS). Based on these risk factors, survival analysis was made by Kaplan-Meier method and their value in prognostic stratification was assessed.

RESULTS

A total of 522 eligible HCC patients with pre-LT PIVKA-II records were finally included in this study. Tumor burden>8 cm, α-fetoprotein>400 ng/ml, histopathologic grade III and PIVKA-II>240 mAU/ml were identified as independent risk factors for DFS. DFS of patients with PIVKA-II≤240 mAU/ml ( N =288) were significantly higher than those with PIVKA-II>240 mAU/ml ( N =234) (1-year, 3-year, and 5-year DFS: 83.2, 77.3, and 75.9% vs. 75.1, 58.5, and 50.5%; P <0.001). Compared with Hangzhou criteria ( N =305), incorporating PIVKA-II into Hangzhou criteria (including tumor burden, α-fetoprotein, and histopathologic grade) increased the number of patients with eligibility for LT by 21.6% but achieved comparable DFS and overall survival.

CONCLUSIONS

Incorporating PIVKA-II into existing LT criteria could increase the number of eligible HCC patients without compromising post-LT outcomes.

Protein induced by vitamin K absence or antagonist II: Experience to date and future directions

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer with high mortality. The realization of precision medicine in HCC relies upon efficient biomarkers. Protein induced by vitamin K absence or antagonist II (PIVKA-II) is an immature prothrombin with insufficient coagulation activity, overexpressing in HCC cells. Previous evidence confirmed the role of PIVKA-II in screening and diagnosing HCC. However, the increased PIVKA-II was observed not only in HCC, but also in non-HCC individuals such as vitamin K deficiency. The joint detection of PIVKA-II and other biomarkers could significantly improve diagnostic accuracy in HCC. Furthermore, PIVKA-II serves as a valuable prognostic predictor, transplantation eligibility, resectability, tumor recurrence, therapeutic efficacy, and malignant tumor behaviors. Additionally, PIVKA-II represents a potential target for agent development to establish new therapeutic strategies. Besides HCC, PIVKA-II also serves as a biomarker of vitamin K status. In this review, we assess the role of PIVKA-II in diagnosis, prediction, and treatment. Over the past decades, substantial progress has been achieved in the application of PIVKA-II. Exploration and innovation are required for further advances in the field of PIVKA-II investigation.

AFP-L3 and DCP are superior to AFP in predicting waitlist dropout in HCC patients: Results of a prospective study

In patients with HCC awaiting liver transplantation (LT), there is a need to identify biomarkers that are superior to AFP in predicting prognosis. AFP-L3 and des-gamma-carboxyprothrombin (DCP) play a role in HCC detection, but their ability to predict waitlist dropout is unknown. In this prospective single-center study commenced in July 2017, 267 HCC patients had all 3 biomarkers obtained at LT listing. Among them, 96.2% received local-regional therapy, and 18.8% had an initial tumor stage beyond Milan criteria requiring tumor downstaging. At listing, median AFP was 7.0 ng/mL (IQR 3.4-21.5), median AFP-L3 was 7.1% (IQR 0.5-12.5), and median DCP was 1.0 ng/mL (IQR 0.2-3.8). After a median follow-up of 19.3 months, 63 (23.6%) experienced waitlist dropout, while 145 (54.3%) received LT, and 59 (22.1%) were still awaiting LT. Using Cox proportional hazards analysis, AFP-L3≥35% and DCP≥7.5 ng/mL were associated with increased waitlist dropout, whereas AFP at all tested cutoffs, including ≥20,≥ 100, and≥250 ng/mL was not. In a multivariable model, AFP-L3≥35% (HR 2.25, p =0.04) and DCP≥7.5 ng/mL (HR 2.20, p =0.02) remained associated with waitlist dropout as did time from HCC diagnosis to listing ≥ 1 year and increasing MELD-Na score. Kaplan-Meier probability of waitlist dropout within 2 years was 21.8% in those with AFP-L3<35% and DCP<7.5 ng/mL, 59.9% with either AFP-L3 or DCP elevated, and 100% for those with both elevated ( p <0.001). In this prospective study, listing AFP-L3% and DCP were superior to AFP in predicting waitlist dropout with the combination of AFP-L3≥35% and DCP≥7.5 ng/mL associated with a 100% risk of waitlist dropout, thus clearly adding prognostic value to AFP alone.

Management of early-stage hepatocellular carcinoma: challenges and strategies for optimal outcomes

Although hepatocellular carcinoma (HCC) is associated with a poor prognosis, management of early-stage HCC is often successful with highly efficacious treatment modalities such as liver transplantation, surgical resection, and radiofrequency ablation. However, unfavorable clinical outcomes have been observed under certain circumstances, even after efficient treatment. Factors that predict unsuitable results after treatment include tumor markers, inflammatory markers, imaging findings reflecting tumor biology, specific outcome indicators for each treatment modality, liver functional reserve, and the technical feasibility of the treatment modalities. Various strategies may overcome these challenges, including the application of reinforced treatment indication criteria with predictive markers reflecting tumor biology, compensation for technical issues with up-to-date technologies, modification of treatment modalities, downstaging with locoregional therapies (such as transarterial chemotherapy or radiotherapy), and recently introduced combination immunotherapies. In this review, we discuss the challenges to achieving optimal outcomes in the management of early-stage HCC and suggest strategies to overcome these obstacles.

Long-Term Outcomes of Liver Transplantation in Hepatocellular Carcinoma with Bile Duct Tumor Thrombus: A Comparison with Portal Vein Tumor Thrombus

Liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) with bile duct tumor thrombus (BDTT) remains controversial. This study analyzed the recurrence and overall survival rates through long-term results after LT in HCC patients with BDTT and compared the results after LT in HCC patients with portal vein tumor thrombus (PVTT). We performed a retrospective study of 45 patients with PVTT, 16 patients with BDTT, and 11 patients with coexisting PVTT and BDTT among HCC patients who underwent LT at a single center from 1999 to 2020. The HCC recurrence rates were 40.4% at 1 year, 30.3.3% at 2 years, and 27.6% at 3 years in the PVTT group; 66.7%, 53.3%, and 46.7% in the BDTT group; and 22.2%, 22.2%, and 0% in the coexisting group (p = 0.183). Overall patient survival rates were 68.4% at 1 year, 54.3% at 2 years, and 41.7% at 3 years in the PVTT group; 81.3%, 62.5%, and 48.2% in the BDTT group; and 63.6%, 27.3%, and 0% in the coexisting group (p = 0.157). In the multivariate analysis, the pre-transplantation model for tumor recurrence after liver transplantation (MoRAL) score and model for end-stage liver disease (MELD) score were found to be independent risk factors for recurrence and survival in all groups. HCC patients with BDTT showed no difference in recurrence and survival compared with HCC patients with PVTT at the long-term follow-up after LT.

Recurrence in patients with totally necrotic nodules of hepatocellular carcinoma after liver transplantation: "totally" an inaccurate description

Purpose

Total necrosis of hepatocellular carcinoma (HCC) achieved via locoregional treatment (LRT) is considered to indicate a lack of tumor viability. Nonetheless, there is insufficient evidence of recurrence after liver transplantation (LT) in patients with such a status. The aim of this study was to investigate the prognosis of patients diagnosed with totally necrotic nodules upon explant hepatectomy after LT.

Methods

We conducted a retrospective study of patients diagnosed with totally necrotic nodules after LT for HCC. A total of 165 patients with HCC who underwent living- or deceased-donor LT from 2000 to 2020 in our hospital were included.

Results

A total of 5 patients (3.0%) exhibited HCC recurrence during a median follow-up of 84 months (range, 4-243 months) after LT. The 5-year overall and recurrence-free survival rates of these patients were 92.8% and 92.2%, respectively. Four patients in the HCC-recurrence group (80.0%) died even after further treatment, including transarterial chemoembolization, surgery, and systemic treatment. Both univariate and multivariate analyses of clinicopathological factors identified a maximum diameter of the totally necrotic nodules of >5 cm as the only factor associated with tumor recurrence following LT (P = 0.005 and P = 0.009, respectively).

Conclusion

Total necrosis of HCC via LRT yielded excellent survival outcomes for patients undergoing LT. Nevertheless, patients with large tumors should be considered at high risk of recurrence after LT, suggesting the need for their active surveillance during the follow-up period.

Personalised management of patients with hepatocellular carcinoma: a multiparametric therapeutic hierarchy concept

Advances in the surgical and systemic therapeutic landscape of hepatocellular carcinoma have increased the complexity of patient management. A dynamic adaptation of the available staging-based algorithms is required to allow flexible therapeutic allocation. In particular, real-world hepatocellular carcinoma management increasingly relies on factors independent of oncological staging, including patients' frailty, comorbid burden, critical tumour location, multiple liver functional parameters, and specific technical contraindications impacting the delivery of treatment and resource availability. In this Policy Review we critically appraise how treatment allocation strictly based on pretreatment staging features has shifted towards a more personalised treatment approach, in which expert tumour boards assume a central role. We propose an evidence-based framework for hepatocellular carcinoma treatment based on the novel concept of multiparametric therapeutic hierarchy, in which different therapeutic options are ordered according to their survival benefit (ie, from surgery to systemic therapy). Moreover, we introduce the concept of converse therapeutic hierarchy, in which therapies are ordered according to their conversion abilities or adjuvant abilities (ie, from systemic therapy to surgery).

Resected Tumor Outcome and Recurrence (RESTORE) Index for Hepatocellular Carcinoma Recurrence after Resection

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the fourth most common cause of cancer-related death worldwide [...].

2022 KLCA-NCC Korea practice guidelines for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

AFP Response to Locoregional Therapy Can Stratify the Risk of Tumor Recurrence in HCC Patients after Living Donor Liver Transplantation

(1) Background: Alpha-fetoprotein (AFP) has been incorporated into the selection criteria of liver transplantation and been used to predict the outcome of hepatocellular carcinoma (HCC) recurrence. Locoregional therapy (LRT) is recommended for bridging or downstaging in HCC patients listed for liver transplantation. The aim of this study was to evaluate the effect of the AFP response to LRT on the outcomes of hepatocellular carcinoma patients after living donor liver transplantation (LDLT). (2) Methods: This retrospective study included 370 HCC LDLT recipients with pretransplant LRT from 2000 to 2016. The patients were divided into four groups according to AFP response to LRT. (3) Results: The nonresponse group had the worst 5-year cumulative recurrence rates whereas the complete-response group (patients with abnormal AFP before LRT and with normal AFP after LRT) had the best 5-year cumulative recurrence rate among the four groups. The 5-year cumulative recurrence rate of the partial-response group (AFP response was over 15% lower) was comparable to the control group. (4) Conclusions: AFP response to LRT can be used to stratify the risk of HCC recurrence after LDLT. If a partial AFP response of over 15% declineis achieved, a comparable result to the control can be expected.

Risk Group Stratification for Recurrence-Free Survival and Early Tumor Recurrence after Radiofrequency Ablation for Hepatocellular Carcinoma

PURPOSE

Although the prognosis after radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) may vary according to different risk levels, there is no standardized follow-up protocol according to each patient's risk. This study aimed to stratify patients according to their risk of recurrence-free survival (RFS) and early (≤2 years) tumor recurrence (ETR) after RFA for HCC based on predictive models and nomograms and to compare the survival times of the risk groups derived from the models.

METHODS

Patients who underwent RFA for a single HCC (≤3 cm) between January 2012 and March 2014 (n = 152) were retrospectively reviewed. Patients were classified into low-, intermediate-, and high-risk groups based on the total nomogram points for RFS and ETR, respectively, and compared for each outcome. Restricted mean survival times (RMSTs) in the three risk groups were evaluated for both RFS and ETR to quantitatively evaluate the difference in survival times.

RESULTS

Predictive models for RFS and ETR were constructed with c-indices of 0.704 and 0.730, respectively. The high- and intermediate-risk groups for RFS had an 8.5-fold and 2.9-fold higher risk of events than the low-risk group (both p < 0.001), respectively. The high- and intermediate-risk groups for ETR had a 17.7-fold and 7.0-fold higher risk than the low-risk group (both p < 0.001), respectively. The RMST in the high-risk group was significantly lower than that in the other two groups 9 months after RFA, and that in the intermediate-risk group became lower than that in the low-risk group after 21 months with RFS and 24 months with ETR.

CONCLUSION

Our predictive models were able to stratify patients into three groups according to their risk of RFS and ETR after RFA for HCC. Differences in RMSTs may be used to establish different follow-up protocols for the three risk groups.

Transarterial chemoembolization as an alternative to radioembolization is associated with earlier tumor recurrence than in radioembolization-eligible patients

Introduction

Although transarterial radioembolization (TARE) using yttrium-90 (⁹⁰Y) is a treatment option for large hepatocellular carcinoma (HCC), a fraction of patients are ineligible for TARE due to high lung shunt fraction (LSF).

Methods

We evaluated if treatment with transarterial chemoembolization (TACE), owing to TARE ineligibility was associated with early HCC progression. Consecutive patients with HCC who were initially TARE candidates were included. Patients with vascular invasion or metastasis were excluded. Primary endpoints were time-to-progression (TTP) and overall survival (OS). The secondary endpoint was objective response rate.

Results

In total, 175 patients were included: 144 underwent TARE (TARE-eligible group) and 31 underwent TACE due to high LSF (TARE-ineligible group). This latter group had larger tumors (13.8 cm vs. 7.8 cm, P<0.001) and higher MoRAL scores (1,385.8 vs. 413.3, P=0.002) than the TARE-eligible group. After balancing baseline characteristics with an inverse probability of treatment weighting (IPTW), the TARE-ineligible group showed shorter TTP [adjusted hazard ratio (aHR)=2.16, 95% confidence interval (CI)=1.14-4.07, P=0.02] and OS (aHR=1.80, 95% CI=0.85-3.80, P=0.12), although the latter was not statistically significant. The TARE-ineligible group had a significantly lower objective response rate than the TARE-eligible group (9.7% vs. 56.9%, P<0.001).

Conclusion

TARE-ineligible patients had larger tumors and higher MoRAL scores than TARE-eligible patients. Treatment with TACE, owing to high LSF, was associated with a shorter TTP even after balancing tumor size and MoRAL scores.

2022 KLCA-NCC Korea Practice Guidelines for the Management of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

Antitumor Effect of Low-Dose of Rapamycin in a Transgenic Mouse Model of Liver Cancer

PURPOSE

We investigate whether low-dose rapamycin is effective in preventing hepatocellular carcinoma (HCC) growth and treating HCC after tumor development in transgenic mice.

MATERIALS AND METHODS

We established transgenic mice with HCC induced by activated HrasG12V and p53 suppression. Transgenic mice were randomly assigned to five experimental groups: negative control, positive control, tacrolimus only, rapamycin only, and tacrolimus plus rapamycin. The mice were further divided into two groups according to time to commencement of immunosuppressant treatment: de novo treatment and post-tumor development.

RESULTS

In the de novo treatment group, marked suppression of tumor growth was observed in the rapamycin only group. In the post-tumor development group, the rapamycin only group displayed no significant suppression of tumor growth, compared to the positive control group. In T lymphocyte subset analysis, the numbers of CD4⁺ effector T cells and CD4⁺ regulatory T cells were significantly lower in the positive control, tacrolimus only, and tacrolimus plus rapamycin groups than the negative control group. Immunohistochemical analysis revealed significantly higher expression of phosphorylated-mTOR, 4E-BP1, and S6K1 in the positive control group than in the rapamycin only group.

CONCLUSION

Low-dose rapamycin might be effective to prevent HCC growth, but may be ineffective as a treatment option after HCC development.

2022 KLCA-NCC Korea practice guidelines for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

Prediction models of hepatocellular carcinoma recurrence after liver transplantation: A comprehensive review

Liver transplantation (LT) is one of the most effective treatments for hepatocellular carcinoma (HCC). Although LT eliminates HCC and greatly reduces recurrence, some patients experience recurrence after LT. Criteria and models for screening patients with a high probability of HCC recurrence after LT, starting with the Milan criteria, have been published. These models have changed over time, but a standard has not been established. We summarized HCC prediction models after LT by focusing on the application of radiologic, serologic, and pathologic factors and recent trends. This review will look at studies that are based on living donor LT and deceased donor LT, as well as studies that downstaging procedures have been performed preoperatively. This ultimately aims to help make decisions for evaluating the HCC state and selecting candidates for LT according to the circumstances of each transplantation center.

Is liquid biopsy the future commutator of decision-making in liver transplantation for hepatocellular carcinoma?

Liver transplant (LT) is the most favorable treatment option for patients with early stage hepatocellular carcinoma (HCC). Numerous attempts have been pursued to establish eligibility criteria and select HCC patients for LT, leading to various systems that essentially integrate clinico-morphological variables. Lacking of sufficient granularity to recapitulate the biological complexity of the disease, all these alternatives display substantial limitations and are thus undeniably imperfect. Liquid biopsy, defined as the molecular analysis of circulating analytes released by a cancer into the bloodstream, was revealed as an incomparable tool in the management of cancers, including HCC. It appears as an ideal candidate to refine selection criteria of LT in HCC. The present comprehensive review analyzed the available literature on this topic. Data in the field, however, remain scarce with only 17 studies. Although rare, these studies provided important and encouraging findings highlighting notable prognostic values and supporting the contribution of liquid biopsy in this specific clinical scenario. These results underpinned the critical and urgent need to intensify and accelerate research on liquid biopsy, in order to determine whether and how liquid biopsy may be integrated in the decision-making of LT in HCC.

The impact of biological features for a better prediction of posttransplant hepatocellular cancer recurrence

PURPOSE OF REVIEW

Morphological criteria (i.e., Milan Criteria) have been considered for a long time to be the best tool for selecting patients with hepatocellular cancer (HCC) waiting for liver transplantation (LT). In the last ten years, a refinement of the selection criteria has been observed, with the introduction of biological tumor characteristics enabling to enlarge the number of potential transplant candidates and to select LT candidates with a lower risk of posttransplant recurrence.

RECENT FINDINGS

Several biological tumor aspects have been explored and validated in international cohorts to expand the ability to predict patients at high risk for recurrence. Alpha-fetoprotein, radiological response to locoregional treatments, and other more recently proposed markers have been principally explored. Moreover, more complex statistical approaches (i.e., deep learning) have been advocated to explore the nonlinear intercorrelations between the investigated features.

SUMMARY

The addition of biological aspects to morphology has improved the ability to discriminate among high- and low-risk patients for recurrence. New prognostic algorithms based on the more sophisticated artificial intelligence approach are further improving the capability to select LT candidates with HCC.

Liver transplantation for HCC: validation of prognostic power of the RETREAT score for recurrence in a UK cohort

BACKGROUND

The Risk Estimation of Tumor Recurrence After Transplant (RETREAT) score as a prognostic index for recurrence has been reported previously and has not been validated outside the USA. Our study has validated the score in a single center UK cohort of patients being transplanted for HCC.

METHODS

LT for HCC between 2008 and 2018 at our center were analyzed. Recurrence-free survival (RFS) was compared by the RETREAT score and validated using Net Reclassification Improvement (NRI) by comparing it to Milan criteria.

RESULTS

346 adult HCC patients were transplanted of whom 313 were included. 28 (8.9%) had a recurrence. Summation of largest diameter and total number of viable tumors (HR = 1.19, p < 0.001), micro-/macro-vascular invasion (HR = 3.74, p = 0.002) and AFP>20 ng/ml (HR = 3.03, p = 0.005) were associated with recurrence on multivariate analysis. RFS decreased with increasing RETREAT score (log-rank p = 0.016). RETREAT performed better than Milan with significant NRI at 1- and 2-years post-transplant (0.43 (p = 0.004) and 0.38 (p = 0.03) respectively).

CONCLUSION

LT outcomes using the revised UK criteria are equivalent to Milan criteria. Further, RETREAT score was validated as a prognostic index for the first time in a UK cohort and may assist risk stratification, selection for adjuvant therapies and guide surveillance.

DCP and AFP-L3 Are Complementary to AFP in Predicting High-Risk Explant Features: Results of a Prospective Study

Among patients with hepatocellular carcinoma (HCC), elevated α-fetoprotein (AFP) has been shown to predict waitlist dropout, high-risk histopathologic features, and inferior post-liver transplant (LT) outcome.^1,2 Nevertheless, many patients with HCC have a normal AFP and yet still experience waitlist dropout or post-LT recurrence.² Because of the degree of imprecision associated with AFP, there is a quest for other biomarkers that may be complementary to or better than AFP in predicting prognosis in LT. Lectin-reactive AFP (AFP-L3) and des-gamma-carboxyprothrombin (DCP) are biomarkers that have been used in conjunction with AFP as HCC surveillance or diagnostic tools.^3,4 However, the utility of these biomarkers in LT for HCC is not established.

The survival strength of younger patients in BCLC stage 0-B of hepatocellular carcinoma: basing on competing risk model

BACKGROUND

The number of young patients with hepatocellular carcinoma (HCC) is increasing, but whether patients of different ages have a survival advantage is unclear. This study was conducted to investigate whether age differences in the Barcelona Clinic Liver Cancer (BCLC) classification system contribute to the long-term survival outcomes of patients with HCC.

METHODS

A total of 1602 patients with HCC admitted to the Beijing Ditan Hospital was included in this study. Patients were divided into younger (≤45 years) and older (> 45 years) groups. Factors determining overall survival and progression-free survival were analyzed using univariate and multivariate analyses with the Kaplan-Meier method and Cox proportional hazard regression model. We calculated the cumulative incidence function using the Fine-Gray model. The effect of mortality on age was also estimated using a restricted cubic spline.

RESULTS

After matching, overall survival and progression-free survival were significantly better in younger patients than in older patients with BCLC stage 0-B (p = 0.015 and p = 0.017, respectively). In BCLC stage 0-B, all-cause mortality increased with age and increased rapidly around the age of 40 years (non-linear, p < 0.05). In BCLC stages 0-B, HCC-related and non-HCC-related deaths significantly differed between younger and older individuals (p = 0.0019).

CONCLUSION

In stage BCLC 0-B, age affects the long-term prognosis of patients.

R3-AFP score is a new composite tool to refine prediction of hepatocellular carcinoma recurrence after liver transplantation

Background & Aims

Patients with hepatocellular carcinoma (HCC) are selected for liver transplantation (LT) based on pre-LT imaging ± alpha-foetoprotein (AFP) level, but discrepancies between pre-LT tumour assessment and explant are frequent. Our aim was to design an explant-based recurrence risk reassessment score to refine prediction of recurrence after LT and provide a framework to guide post-LT management.

Methods

Adult patients who underwent transplantation between 2000 and 2018 for HCC in 47 centres were included. A prediction model for recurrence was developed using competing-risk regression analysis in a European training cohort (TC; n = 1,359) and tested in a Latin American validation cohort (VC; n=1,085).

Results

In the TC, 76.4% of patients with HCC met the Milan criteria, and 89.9% had an AFP score of ≤2 points. The recurrence risk reassessment (R3)-AFP model was designed based on variables independently associated with recurrence in the TC (with associated weights): ≥4 nodules (sub-distribution of hazard ratio [SHR] = 1.88, 1 point), size of largest nodule (3–6 cm: SHR = 1.83, 1 point; >6 cm: SHR = 5.82, 5 points), presence of microvascular invasion (MVI; SHR = 2.69, 2 points), nuclear grade >II (SHR = 1.20, 1 point), and last pre-LT AFP value (101–1,000 ng/ml: SHR = 1.57, 1 point; >1,000 ng/ml: SHR = 2.83, 2 points). Wolber’s c-index was 0.76 (95% CI 0.72–0.80), significantly superior to an R3 model without AFP (0.75; 95% CI 0.72–0.79; p = 0.01). Four 5-year recurrence risk categories were identified: very low (score = 0; 5.5%), low (1–2 points; 15.1%), high (3–6 points; 39.1%), and very high (>6 points; 73.9%). The R3-AFP score performed well in the VC (Wolber’s c-index of 0.78; 95% CI 0.73–0.83).

Conclusions

The R3 score including the last pre-LT AFP value (R3-AFP score) provides a user-friendly, standardised framework to design post-LT surveillance strategies, protocols, or adjuvant therapy trials for HCC not limited to the Milan criteria.

Clinical Trials Registration

NCT03775863.

Lay summary

Considering discrepancies between pre-LT tumour assessment and explant are frequent, reassessing the risk of recurrence after LT is critical to further refine the management of patients with HCC. In a large and international cohort of patients who underwent transplantation for HCC, we designed and validated the R3-AFP model based on variables independently associated with recurrence post-LT (number of nodules, size of largest nodule, presence of MVI, nuclear grade, and last pre-LT AFP value). The R3-AFP model including last available pre-LT AFP value outperformed the original R3 model only based on explant features. The final R3-AFP scoring system provides a robust framework to design post-LT surveillance strategies, protocols, or adjuvant therapy trials, irrespective of criteria used to select patients with HCC for LT.

•

Discrepancies between pretransplant tumour assessment and liver explant are frequent.

•

The R3-AFP predictive model of recurrence was designed and validated in a large and international cohort of patients transplanted for HCC.

•

The components of the final model are the following: number of nodules, size of the largest nodule, presence of MVI, nuclear grade, and last pre-LT AFP value.

•

The R3-AFP model including the last available pre-LT AFP value outperformed the original R3 model only based on explant features.

•

The final R3-AFP scoring system provides a standardised framework to refine post-LT management of patients, irrespective of criteria used to select patients with HCC for LT.

Liver Transplantation for Hepatocellular Carcinoma: How Should We Improve the Thresholds?

Simple Summary

The ideal treatment for hepatocellular carcinoma (HCC) is liver transplantation (LT), which both eliminates the HCC and cures the diseased liver. Once considered an experimental treatment with dismal survival rates, LT for HCC entered a new era with the establishment of the Milan criteria over 20 years ago. However, over the last two decades, the Milan criteria, which are based on tumor morphology, have come under intense scrutiny and are now largely regarded as too restrictive, and limit the access of transplantation for many patients who would otherwise achieve good clinical outcomes. The liver transplant community has been making every effort to reach a goal of establishing more reliable selection criteria. This article addresses how the criteria have been extended, as well as the concept of pre-transplant down-staging to maximize the eligibility.

Abstract

Hepatocellular carcinoma (HCC) is the third highest cause of cancer-related mortality, and liver transplantation is the ideal treatment for this disease. The Milan criteria provided the opportunity for HCC patients to undergo LT with favorable outcomes and have been the international gold standard and benchmark. With the accumulation of data, however, the Milan criteria are not regarded as too restrictive. After the implementation of the Milan criteria, many extended criteria have been proposed, which increases the limitations regarding the morphological tumor burden, and incorporates the tumor’s biological behavior using surrogate markers. The paradigm for the patient selection for LT appears to be shifting from morphologic criteria to a combination of biologic, histologic, and morphologic criteria, and to the establishment of a model for predicting post-transplant recurrence and outcomes. This review article aims to characterize the various patient selection criteria for LT, with reference to several surrogate markers for the biological behavior of HCC (e.g., AFP, PIVKA-II, NLR, 18F-FDG PET/CT, liquid biopsy), and the response to locoregional therapy. Furthermore, the allocation rules in each country and the present evidence on the role of down-staging large tumors are addressed.

Predicting recurrence of hepatocellular carcinoma after liver transplantation using a novel model that incorporates tumor and donor-related factors

Evidence suggests that liver graft quality impacts on posttransplant recurrence of hepatocellular carcinoma (HCC). As of today, selection criteria only use variables related to tumor characteristics. Within the Scientific Registry of Transplant Recipients, we identified patients with HCC who underwent liver transplantation between 2004 and 2016 (development cohort, n = 10 887). Based on tumor recurrence rates, we fitted a competing-risk regression incorporating tumor- and donor-related factors, and we developed a prognostic score. Results were validated both internally and externally in the Australia and New Zealand Liver Transplant Registry. Total tumor diameter (subhazard ratio [sub-HR] 1.52 [1.28-1.81]), alpha-feto protein (sub-HR 1.27 [1.23-1.32], recipient male gender (sub-HR 1.43 [1.18-1.74]), elevated donor body mass index (sub-HR 1.26 [1.01-1.58]), and shared graft allocation policy (sub-HR 1.20 [1.01-1.43]) were independently associated with tumor recurrence. We next developed the Darlica score (sub-HR 2.72 [2.41-3.08] P < 0.001) that allows identifying risky combinations between a given donor and a given recipient. Results were validated internally (n = 3 629) and externally in the Australia and New Zealand Liver Transplant Registry (n = 370). The current score is based on variables that are readily available at the time of graft offer. It allows identifying hazardous donor-recipient combinations in terms of risk of tumor recurrence and overall survival.

Outcomes of Living Donor Liver Transplantation in Patients With a History of Ruptured Hepatocellular Carcinoma

Background: Liver transplantation (LT) is considered a contraindication in patients with a history of hepatocellular carcinoma (HCC) rupture because ruptured HCCs are classified as T4 in the current American Joint Committee on Cancer TNM system. This study aimed to assess living donor liver transplantation (LDLT) in these patients and elucidate the factors that may have affected their outcomes.

Methods: Data of patients with a history of ruptured HCC who underwent LDLT between January 1999 and December 2019 were retrospectively reviewed.

Results: Among 789 patients who underwent LDLT for HCC, five (0.64%) had a history of HCC rupture. Three patients (60%) were treated with transarterial chemoembolization (TACE) or transarterial embolization (TAE) for hemostasis, and two patients (40%) achieved spontaneous hemostasis. One of two patients who achieved spontaneous hemostasis underwent surgical resection and LT at 1 week and 6 years after the rupture, respectively. The other patient underwent LT 2 days after the rupture. Four patients (80%) survived for >5 years, while two patients (40%) experienced recurrence and succumbed during the median follow-up duration of 85.3 months (range, 12.4–182.7). The recurrence first developed at 4.3 and 17.0 months after LT; these patients were managed well using surgical resection for peritoneal seeding and TACE for intrahepatic HCC.

Conclusion: LDLT can be considered a treatment method even in patients with a history of HCC rupture after full evaluation of tumor biology and risk of recurrence.

Downstaging Outcomes for Hepatocellular Carcinoma: Results From the Multicenter Evaluation of Reduction in Tumor Size before Liver Transplantation (MERITS-LT) Consortium

BACKGROUND & AIMS

United Network of Organ Sharing (UNOS) has adopted uniform criteria for downstaging (UNOS-DS) of hepatocellular carcinoma (HCC) before liver transplantation (LT), but the downstaging success rate and intention-to-treat outcomes across broad geographic regions are unknown.

METHODS

In this first multiregional study (7 centers, 4 UNOS regions), 209 consecutive patients with HCC undergoing downstaging based on UNOS-DS criteria were prospectively evaluated from 2016 to 2019.

RESULTS

Probability of successful downstaging to Milan criteria and dropout at 2 years from the initial downstaging procedure was 87.7% and 37.3%, respectively. Pretreatment with lectin-reactive α-fetoprotein ≥10% (hazard ratio, 3.7; P = .02) was associated with increased dropout risk. When chemoembolization (n = 132) and yttrium-90 radioembolization (n = 62) were compared as the initial downstaging treatment, there were no differences in Modified Response Evaluation Criteria In Solid Tumors response, probability of or time to successful downstaging, waiting list dropout, or LT. Probability of LT at 3 years was 46.6% after a median of 17.2 months. In the explant, 17.5% had vascular invasion, and 42.8% exceeded Milan criteria (understaging). The only factor associated with understaging was the sum of the number of lesions plus largest tumor diameter on the last pre-LT imaging, and the odds of understaging increased by 35% per 1-unit increase in this sum. Post-LT survival at 2 years was 95%, and HCC recurrence occurred in 7.9%.

CONCLUSION

In this first prospective multiregional study based on UNOS-DS criteria, we observed a successful downstaging rate of >80% and similar efficacy of chemoembolization and yttrium-90 radioembolization as the initial downstaging treatment. A high rate of tumor understaging was observed despite excellent 2-year post-LT survival of 95%. Additional LRT to reduce viable tumor burden may reduce tumor understaging.

Immunological Markers, Prognostic Factors and Challenges Following Curative Treatments for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortalities worldwide. Patients with early-stage HCC are eligible for curative treatments, such as surgical resection, liver transplantation (LT) and percutaneous ablation. Although curative treatments provide excellent long-term survival, almost 70–80% of patients experience HCC recurrence after curative treatments. Tumor-related factors, including tumor size, number and differentiation, and underlying liver disease, are well-known risk factors for recurrence following curative therapies. Moreover, the tumor microenvironment (TME) also plays a key role in the recurrence of HCC. Many immunosuppressive mechanisms, such as an increase in regulatory T cells and myeloid-derived suppressor cells with a decrease in cytotoxic T cells, are implicated in HCC recurrence. These suppressive TMEs are also modulated by several factors and pathways, including mammalian target of rapamycin signaling, vascular endothelial growth factor, programmed cell death protein 1 and its ligand 1. Based on these mechanisms and the promising results of immune checkpoint blockers (ICBs) in advanced HCC, there have been several ongoing adjuvant studies using a single or combination of ICB following curative treatments in HCC. In this review, we strive to provide biologic and immunological markers, prognostic factors, and challenges associated with clinical outcomes after curative treatments, including resection, LT and ablation.

Liver Transplantation in Patients with Hepatocellular Carcinoma beyond the Milan Criteria: A Comprehensive Review

The Milan criteria (MC) were developed more than 20 years ago and are still considered the benchmark for liver transplantation (LT) in patients with hepatocellular carcinoma (HCC). However, the strict application of MC might exclude some patients who may receive a clinical benefit of LT. Several expanded criteria have been proposed. Some of these consider pretransplant morphological and biological variables of the tumor, others consider post-LT variables such as the histology of the tumor, and others combine pre- and post-LT variables. More recently, the HCC response to locoregional treatments before transplantation emerged as a surrogate marker of the biological aggressiveness of the tumor to be used as a better selection criterion for LT in patients beyond the MC at presentation. This essential review aims to present the current data on the pretransplant selection criteria for LT in patients with HCC exceeding the MC at presentation based on morphological and histological characteristics of the tumor and to critically discuss those that have been validated in clinical practice. Moreover, the role of HCC biological markers and the tumor response to downstaging procedures as new tools for selecting patients with a tumor burden outside of the MC for LT is evaluated.

Tailored Prediction Model of Survival after Liver Transplantation for Hepatocellular Carcinoma

This study aimed to create a tailored prediction model of hepatocellular carcinoma (HCC)-specific survival after transplantation based on pre-transplant parameters. Data collected from June 2006 to July 2018 were used as a derivation dataset and analyzed to create an HCC-specific survival prediction model by combining significant risk factors. Separate data were collected from January 2014 to June 2018 for validation. The prediction model was validated internally and externally. The data were divided into three groups based on risk scores derived from the hazard ratio. A combination of patient demographic, laboratory, radiological data, and tumor-specific characteristics that showed a good prediction of HCC-specific death at a specific time (t) were chosen. Internal and external validations with Uno’s C-index were 0.79 and 0.75 (95% confidence interval (CI) 0.65–0.86), respectively. The predicted survival after liver transplantation for HCC (SALT) at a time “t” was calculated using the formula: [1 − (HCC-specific death(t’))] × 100. The 5-year HCC-specific death and recurrence rates in the low-risk group were 2% and 5%; the intermediate-risk group was 12% and 14%, and in the high-risk group were 71% and 82%. Our HCC-specific survival predictor named “SALT calculator” could provide accurate information about expected survival tailored for patients undergoing transplantation for HCC.

Living donor liver transplantation for hepatocellular carcinoma in Indian patients- Is the scenario different?

BACKGROUND

Living donor liver transplant (LDLT) for hepatocellular carcinoma (HCC) has been controversial in terms of selection and outcome. We share our experience of LDLT for HCC in Indian patients.

METHODS

Retrospective analysis of patients undergoing LDLT for HCC discovered either preoperatively or incidentally on explant pathology was done. Preoperative characteristics and explant histopathology findings were recorded. Overall, recurrence-free survival and factors predicting recurrence were analyzed.

RESULTS

Six hundred and eleven LDLT were performed between June 2011 and October 2019. HCC constituted 6.5% (n = 53) of transplant activity. Forty had preoperative diagnosis, while 13 were detected incidentally. The median model for end-stage liver disease (MELD) score was 18 for patients with HCC. Only in 10 patients (19%), HCC was the primary indication for liver transplant (LT), and the rest had undergone transplant for progressive decompensation. Thirty-two patients were within up-to-7, while 21 were outside up-to-7 criteria. Overall 5-year survival was 85.4% and recurrence-free survival was 83.3% after a median follow-up of 35 months (13-59). This was similar to LDLT for other indications (81.2% at 5 years). Risk Estimation of Tumor Recurrence After Transplant (RETREAT) score was best able to predict recurrence (p = 0.03) with odds ratio of 6.8.

CONCLUSION

Patients with HCC in India present late for liver transplant. Most patients have some form of decompensation before they undergo LT. In selected patients, overall survival was comparable with other indications for LDLT with acceptable recurrence rates. RETREAT score was best to predict recurrence.

Hepatocellular cancer selection systems and liver transplantation: from the tower of babel to an ideal comprehensive score

The Milan criteria (MC) remain the cornerstone for the selection of patients with hepatocellular cancer (HCC) to be listed for liver transplantation (LT). Recently, several expanded criteria have been proposed to increase the transplantability of HCC patients without compromising their (oncologic) outcome. This paper aims to systematically review the different reported HCC-LT selection systems looking thereby at their ability to increase the number of transplantable patients and the overall survival and oncological outcome. A systematic review of the literature covering the period 1993 (date of the first reported HCC-LT selection system)–2021 identified 59 different inclusion criteria of HCC for LT. Among the 59 studies reporting HCC-LT selection systems, 15 (28.3%) were exclusively based on morphological aspects of the tumor; 29 (54.7%) included biologic, seven (13.2%) radiological, and two (3.8%) only included pathological tumor features. Overall, 31% more patients could be transplanted when adhering to the new HCC-LT selection systems. Despite the increased number of LT, 5-year patient and disease-free survival rates were similar between MC-IN and MC-OUT/new HCC-LT-IN criteria. A careful extension of the inclusion criteria should allow many more patients to access a potentially curative LT without compromising their outcome. The development of a widely accepted “comprehensive” HCC-LT Score able to offer a fair chance of justified transplantation to more patients should become a priority within the liver transplant community. Further studies are needed to develop internationally accepted, expanded selection criteria for liver transplantation of HCC patients.

The Key Role of Staging Definitions for Assessment of Downstaging for Hepatocellular Carcinoma

The success of liver transplant (LT) for hepatocellular carcinoma (HCC) is dependent on accurate tumor staging using validated imaging criteria, and adherence to acceptable criteria based on tumor size and number. Other factors including α-fetoprotein (AFP) and response to local regional therapy (LRT) have now played a larger role in candidate selection. Tumor downstaging is defined as reduction in the size of viable tumors using LRT to meet acceptable criteria for LT, and serves as a selection tool for a subgroup of HCC with more favorable biology. The application of tumor downstaging requires a structured approach involving three key components in tumor staging-initial tumor stage and eligibility criteria, tumor viability assessment following LRT, and target tumor stage prior to LT-and incorporation of AFP into staging and treatment response assessments. In this review, we provide in-depth discussions of the key role of these staging definitions in ensuring successful outcome.

Experience With LDLT in Patients With Hepatocellular Carcinoma and Portal Vein Tumor Thrombosis Postdownstaging

BACKGROUND

Median survival in patients with hepatocellular carcinoma (HCC) and portal vein tumor thrombosis (PVTT) is 2-6 months; conventionally liver transplantation is contraindicated.

METHODS

We studied outcomes following living donor liver transplantation (LDLT) post-PVTT downstaging (DS) with stereotactic body radiotherapy (SBRT), and tumor ablation (with transarterial chemo- or radio-embolization).

RESULTS

Of 2348 consecutive LDLTs, 451 were for HCC, including 25 with PVTT (mainly Vp1-3) after successful DS and 20 with Vp1/2 PVTT without previous treatment. DS was attempted in 43, was successful in 27 (63%), and 25 underwent LDLT. Median alpha fetoprotein (AFP) at diagnosis and pre-LDLT were 78.1 ng/mL (3-58 200) and 55 ng/mL (2-7320), respectively. Mean DS to LDLT time was 10.2 weeks (5-16). Excluding 2 postoperative deaths, 1- and 5-year overall survival (OS) and recurrence-free survival (RFS) were 82%, 57%, and 77%, 51%, respectively, comparable to survival in 382 HCC patients without PVTT undergoing upfront LDLT (5-y OS 65%, P = 0.06; RFS 66%, P = 0.33, respectively). There was a trend toward better OS in DS+LDLT versus non-DS LDLT group (5-y OS/RFS-48%/40%). OS was significantly better than in HCC-PVTT patients receiving no intervention or palliative Sorafenib alone (1-y OS of 0%) or Sorafenib with TARE/SBRT (2-y OS of 17%) at our center during the study period. Initial AFP <400 ng/mL and AFP fall (initial minus pre-LDLT) >2000 ng/mL predicted better RFS; Grade III/IV predicted worse OS in DS patients.

CONCLUSIONS

HCC patients with PVTT can achieve acceptable survival with LDLT after successful DS. Low initial AFP level, a significant drop in AFP with DS and low tumor grade, favorably influence survival in these patients.

Incorporating Tumor Biology to Predict Hepatocellular Carcinoma Recurrence in Patients Undergoing Living Donor Liver Transplantation Using Expanded Selection Criteria

Conventional selection criteria for liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) are based on tumour size/number only, and do not consider vital surrogates of tumor biology such as alpha-fetoprotein (AFP) and tumor [¹⁸ F]fluorodeoxyglucose positron emission tomography ([¹⁸ F]FDG PET) avidity. We analyzed survival outcomes, and predictors of HCC recurrence in 405 patients with cirrhosis and HCC (HCC-cirr) who underwent living donor LT (LDLT) using our expanded selection criteria: no extrahepatic disease or major vascular invasion, irrespective of tumor size/number. Fifty-one percent patients had tumours beyond Milan, and 43% beyond the University of California San Francisco [UCSF] criteria. The 5-year overall survival (OS) and recurrence-free survival (RFS) were 64% and 70%, respectively. Three preoperatively available factors predicted recurrence: pre-LT AFP ≥100 ng/mL (P = 0.005; hazard ratio [HR], 2.190), tumor burden beyond the UCSF criteria (P = 0.001; HR, 2.640), and [¹⁸ F]FDG PET avidity (P = 0.004; HR, 2.442). A prognostic model based on the number and combination of the aforementioned preoperative risk factors was developed using a competing-risk RFS model. Three risk groups were identified: low (none or a single risk factor present, 9.3% recurrence), moderate (AFP ≥100 ng/mL and [¹⁸ F]FDG PET avidity, or beyond UCSF tumor and [¹⁸ F]FDG PET avidity, 25% recurrence), and high (AFP ≥100 ng/mL and beyond UCSF, or presence of all 3 risk factors, 46% recurrence). Acceptable long-term outcomes were achieved using our expanded selection criteria. Our prognostic model to predict recurrence based on preoperative biological and morphological factors could guide pretransplant management (downstaging versus upfront LDLT) with the aim of reducing post-LDLT recurrence.

Sirolimus Prolongs Survival after Living Donor Liver Transplantation for Hepatocellular Carcinoma Beyond Milan Criteria: A Prospective, Randomised, Open-Label, Multicentre Phase 2 Trial

Sirolimus (SRL) has been reported to benefit patients undergoing liver transplantation (LT) for hepatocellular carcinoma (HCC). This study aimed to compare SRL with tacrolimus (TAC) in living-donor LT (LDLT) recipients beyond the Milan criteria. This study was initially designed to enrol 45 recipients who underwent LDLT for HCC beyond the Milan criteria. At 1 month after LT, the patients were randomly assigned to either SRL or TAC-based treatment, with both groups receiving mycophenolate mofetil. The primary outcome was three-year recurrence-free survival (RFS) and the secondary outcome was overall survival (OS). A total of 42 patients completed the study. HCC recurrence occurred in 8 of 22 (36.4%) patients in the SRL group and in 5 of 22 (25%) patients in the TAC group. No differences in RFS and OS were found between the two groups in simple comparison. The type of immunosuppressant remained a nonsignificant factor for recurrence in multivariate analysis; however, SRL significantly prolonged OS (TAC hazard ratio: 15 [1.3–172.85], p = 0.03) after adjusting for alpha-fetoprotein and positron emission tomography standardised uptake value ratio (tumour/background liver). In conclusion, SRL does not decrease HCC recurrence but prolongs OS after LDLT for HCC beyond the Milan criteria.

A 2020 update on liver transplant for hepatocellular carcinoma

INTRODUCTION

Hepatocellular carcinoma is the most frequent liver tumor and is associated with chronic liver disease in 90% of cases. In selected cases, liver transplantation represents an effective therapy with excellent overall survival.

AREA COVERED

Since the introduction of Milan criteria in 1996, numerous alternative selection systems to LT for HCC patients have been proposed. Debate remains about how best to select HCC patients for transplant and how to prioritize them on the waiting list.

EXPERT OPINION

The selection of the best scoring system to propose in the context of LT for HCC is far to be identified. In this review, we analyze and categorize the various selection systems, assessing their roles in the different decisional phases.

Novel Model to Predict HCC Recurrence after Liver Transplantation Obtained Using Deep Learning: A Multicenter Study

Simple Summary

Although several models have been developed to extend the criteria for liver transplantation in hepatocellular carcinoma beyond the Milan criteria, there are still no standard criteria. This study aimed to develop and validate a novel model to predict hepatocellular carcinoma recurrence after liver transplantation by adopting artificial intelligence (MoRAL-AI). The MoRAL-AI showed significantly better discrimination (c-index = 0.75) than previous models in the independent validation cohort: the Milan (c-index = 0.64), MoRAL (c-index = 0.69), UCSF (c-index = 0.62), up-to-seven (c-index = 0.50), and Kyoto (c-index = 0.50) criteria (all p < 0.001). We assessed the weighted parameters for tumor recurrence in the MoRAL-AI with the deep learning method: tumor diameter, followed by alpha-fetoprotein, age, and PIVKA-II.

Abstract

Several models have been developed using conventional regression approaches to extend the criteria for liver transplantation (LT) in hepatocellular carcinoma (HCC) beyond the Milan criteria. We aimed to develop a novel model to predict tumor recurrence after LT by adopting artificial intelligence (MoRAL-AI). This study included 563 patients who underwent LT for HCC at three large LT centers in Korea. Derivation (n = 349) and validation (n = 214) cohorts were independently established. The primary outcome was time-to-recurrence after LT. A MoRAL-AI was derived from the derivation cohort with a residual block-based deep neural network. The median follow-up duration was 74.7 months (interquartile-range, 18.5–107.4); 204 patients (36.2%) had HCC beyond the Milan criteria. The optimal model consisted of seven layers including two residual blocks. In the validation cohort, the MoRAL-AI showed significantly better discrimination function (c-index = 0.75) than the Milan (c-index = 0.64), MoRAL (c-index = 0.69), University of California San Francisco (c-index = 0.62), up-to-seven (c-index = 0.50), and Kyoto (c-index = 0.50) criteria (all p < 0.001). The largest weighted parameter in the MoRAL-AI was tumor diameter, followed by alpha-fetoprotein, age, and protein induced by vitamin K absence-II. The MoRAL-AI had better predictability of tumor recurrence after LT than conventional models. The MoRAL-AI can also evolve with further data.

When to call it off: defining transplant candidacy limits in liver donor liver transplantation for hepatocellular carcinoma

Background

Living donor liver transplantation (LDLT) is an acceptable treatment option for hepatocellular carcinoma (HCC). Traditional transplant criteria aim at best utilization of donor organs with low risk of post transplant recurrence. In LDLT, long term recurrence free survival (RFS) of 50% is considered acceptable. The objective of the current study was to determine preoperative factors associated with high recurrence rates in LDLT.

Methods

Between April 2012 and December 2019, 898 LDLTs were performed at our center. Out of these, 242 were confirmed to have HCC on explant histopathology. We looked at preoperative factors associated with ≤ 50%RFS at 4 years. For survival analysis, Kaplan Meier curves were used and Cox regression analysis was used to identify independent predictors of recurrence.

Results

Median AFP was 14.4(0.7–11,326.7) ng/ml. Median tumor size was 2.8(range = 0.1–11) cm and tumor number was 2(range = 1–15). On multivariate analysis, AFP > 600 ng/ml [HR:6, CI: 1.9–18.4, P = 0.002] and microvascular invasion (MVI) [HR:5.8, CI: 2.5–13.4, P <  0.001] were independent predictors of 4 year RFS ≤ 50%. When AFP was > 600 ng/ml, MVI was seen in 88.9% tumors with poor grade and 75% of tumors outside University of California San Francisco criteria. Estimated 4 year RFS was 78% for the entire cohort. When AFP was < 600 ng/ml, 4 year RFS for well-moderate and poor grade tumors was 88 and 73%. With AFP > 600 ng/ml, RFS was 53% and 0 with well-moderate and poor grade tumors respectively (P <  0.001).

Conclusion

Patients with AFP < 600 ng/ml have acceptable outcomes after LDLT. In patients with AFP > 600 ng/ml, a preoperative biopsy to rule out poor differentiation should be considered for patient selection.

Risk assessment criteria in liver transplantation for hepatocellular carcinoma: proposal to improve transplant oncology

Liver transplantation for hepatocellular carcinoma has proved to be a highly effective cure if the right patient can be selected. Milan criteria has traditionally guided physicians toward appropriate liver allocation but changes in clinical practice, patient populations and recent developments in biomarkers are decreasing Milan criteria’s utility. At the same time, the literature has flooded with a diversity of new criteria that demonstrate strong predictive power and are better suited for current clinical practice. In this article, the utility of newly proposed criteria will be reviewed and important issues to improve future criteria will be addressed in hopes of opening a discussion on how key questions surrounding criteria for liver transplantation of hepatocellular carcinoma can be answered.

Homocysteine: A novel prognostic biomarker in liver transplantation for alpha-fetoprotein- negative hepatocellular carcinoma

BACKGROUND

Precise recipient selection optimizes the prognosis of liver transplantation (LT) for hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) is the most commonly used biomarker for diagnosis and prognosis of HCC in the clinical context. As a crucial molecule in methionine cycle, homocysteine (Hcy) level has been proved to be related to HCC progression and metastasis.

OBJECTIVE

We aimed to explore the prognostic capacity of pre-transplant serum Hcy level in LT for HCC.

METHODS

This study retrospectively enrolled 161 HCC patients who had underwent LT from donation after cardiac death (DCD) in the First Affiliated Hospital of Zhejiang University from 2015.01.01 to 2018.09.01. Pre-transplant serum Hcy level was incorporated into statistical analysis together with other clinical parameters and pathological features.

RESULTS

From an overall perspective, significant difference was observed in Hcy level between recurrence (n= 61) and non-recurrence group (n= 100) though subsequent analysis showed unsatisfactory predicting performance. In the whole cohort, multivariate analysis showed that lnAFP (p= 0.010) and Milan criteria (MC, p< 0.001) were independent risk factors of HCC recurrence after LT. MA score based on MC and lnAFP performed well in predicting post-LT tumor recurrence with the AUROC at 0.836 (p< 0.001) and 3-year recurrence-free survival rate at 96.8% (p< 0.001) in the low risk group (n= 69). According to the clinical practice, serum concentration lower than 20 μg/L is considered as normal range of AFP. Elevated pre-transplant serum AFP (> 20 μg/L) predicts high HCC recurrence after LT. We further divided the 161 recipients into AFP- group (n= 77, AFP ⩽ 20 μg/L) and AFP+ group (n= 84, AFP > 20 μg/L). MA score was still well presented in the AFP+ group and the AUROC for tumor recurrence was 0.823 (p< 0.001), whereas the predicting accuracy was reduced in AFP- group (AUROC: 0.754, P< 0.001). After subsequent analysis, we found that elevated pre-transplant Hcy level (> 12.75 μmol/L) predicted increased tumor recurrence risk in AFP- group. The 3-year recurrence-free survival rates were 92.0% and 53.7% (p< 0.001) in low Hcy subgroup (n= 40) and high Hcy subgroup (n= 37) respectively. Multivariate analysis showed that Hcy (p= 0.040) and Milan criteria (p= 0.003) were independent risk factors for post-transplant tumor recurrence in AFP- group. Further combination of Hcy level and Milan criteria identified a subgroup of AFP- recipients with acceptable outcomes even though beyond Milan criteria (3-year recurrence-free survival rate: 77.7%, p< 0.001).

CONCLUSION

As a classic predictor in HCC prognosis, AFP performed well in our study cohort when combined with Milan criteria. Homocysteine was an effective prognostic biomarker in LT for AFP- hepatocellular carcinoma. In recipients exceeding Milan criteria, acceptable post-transplant outcome could be seen in those with low Hcy and AFP level.

Shadows Behind Using Simple Risk Models in Selection of Hepatocellular Carcinoma Patients for Liver Transplantation

OBJECTIVE

To assess the potential influence of replacing Milan criteria with simple risk scores on outcomes of hepatocellular carcinoma (HCC) patients undergoing liver transplantation.

SUMMARY BACKGROUND DATA

Several risk scores combining morphological and biological features were recently proposed for precise selection of HCC patients for transplantation.

METHODS

This retrospective study included 282 HCC liver transplant recipients. Recurrence-free survival (RFS), the primary outcome measure, was evaluated according to Metroticket 2.0 model and French AFP model with Milan criteria serving as benchmark.

RESULTS

Patients were well stratified with respect to RFS by Milan criteria, Metroticket 2.0 criteria, and AFP model cut-off ≤2 points (all P < 0.001) with c-statistics of 0.680, 0.695, and 0.681, respectively. Neither Metroticket 2.0 criteria (0.014, Z = 0.023; P = 0.509) nor AFP model (-0.014, Z = -0.021; P = 0.492) provided significant net reclassification improvement. Both patients within the Metroticket 2.0 criteria and AFP model ≤2 points exhibited heterogeneous recurrence risk, dependent upon alpha-fetoprotein (P = 0.026) and tumor number (P = 0.024), respectively. RFS of patients beyond Milan but within Metroticket 2.0 criteria (75.3%) or with AFP model ≤2 points (74.1%) was inferior to that observed for patients within Milan criteria (87.1%; P = 0.067 and P = 0.045, respectively). Corresponding microvascular invasion rates were 37.2% and 50.0%, compared with 13.6% in patients within Milan criteria (both P < 0.001). Moreover, Milan-out status was associated with significantly higher recurrence risk in subgroups within Metroticket 2.0 criteria (P = 0.021) or AFP model ≤2 points (P = 0.014).

CONCLUSION

Utilization of simple risk scores for liver transplant eligibility assessment leads to selection of patients at higher risk of posttransplant HCC recurrence.