Including mRECIST in the Metroticket 2.0 criteria improves prediction of hepatocellular carcinoma-related death after liver transplant

New Scenarios in Liver Transplantation for Hepatocellular Carcinoma

BACKGROUND AND AIMS

Despite liver transplantation (LT) is considered the optimal treatment for hepatocellular carcinoma (HCC), particularly in patients with impaired liver function, the shortage of donors has forced the application of very restrictive criteria for selecting ideal candidates for whom LT can offer the best outcome. With the evolving LT landscape due to the advent of direct-acting antivirals (DAAs) and the steady increase in donors, major efforts have been made to expand the transplant eligibility criteria for HCC. In addition, the emergence of immune checkpoint inhibitors (ICIs) for the treatment of HCC, with demonstrated efficacy in earlier stages, has revolutionized the therapeutic approach for these patients, and their integration in the setting of LT is challenging. Management of immunological compromise from ICIs, including the wash-out period before LT and post-LT immunosuppression adjustments, is crucial to balance the risk of graft rejection against HCC recurrence. Additionally, the effects of increased immunosuppression on non-hepatic complications must be understood to prevent them from becoming obstacles to long-term OS.

METHODS AND RESULTS

In this review, we will evaluate the emerging evidence and its implications for the future of LT in HCC. Addressing these novel challenges and opportunities, while integrating the current clinical evidence with predictive algorithms, would ensure a fair balance between individual patient needs and the overall population benefit in the LT system.

Comparative Validation of Prediction Models for HCC Outcomes in Living Donor Liver Transplantation: Superiority of Tumor Markers to Imaging Study

BACKGROUND

Living donor liver transplantation (LDLT) offers timely curative treatment for unresectable hepatocellular carcinoma (HCC). This study aims to validate and compare previous prediction models for HCC outcomes in 488 LDLT recipients.

METHODS

For 488 patients who underwent LDLT for HCC, pretransplant imaging studies assessed by modified RECSIT criteria, tumor markers such as alpha feto-protein (AFP) and protein induced by vitamin K absence or antagonist-II (PIVKA II), and explant pathology were recruited. C-index of models for the HCC outcomes was compared, followed by further investigation for the predictive performances of the best model.

RESULTS

We found MoRAL (11√PIVKA-II + 2√AFP) demonstrated a higher C-index for HCC recurrence than other models that included radiologically viable tumor number and/or size (MoRAL: 0.709, Milan: 0.537, UCSF: 0.575, Up-to-7: 0.572, French AFP: 0.634, Pre-MORAL: 0.637, HALT-HCC: 0.626, Metroticket2.0: 0.629) and also had the highest C-index for HCC-specific deaths (0.706). Five-year HCC recurrence was well stratified upon dividing the patients into three groups by MoRAL cutoffs (11.9% for MoRAL < 100, 29.6% for MoRAL 100-200, and 48.6% for MoRAL > 200, p < 0.001). However, patients with major vessel invasion or portal vein tumor thrombus showed similarly high HCC recurrence regardless of this grouping (p = 0.612).

CONCLUSION

The MoRAL, based on tumor markers, showed the best predictive performance for HCC recurrence and HCC-specific death among the validated models, except in cases with major vessel invasion or portal vein tumor thrombus.

Liver Transplantation for Hepatocellular Carcinoma: An Expanding Cornerstone of Care in the Era of Immunotherapy

Liver transplantation (LT) has been accepted as a cornerstone of care in hepatocellular carcinoma (HCC) for almost three decades. In recent years, its role has been evolving to include patients with disease burden beyond the widely used Milan criteria. The integration of dynamic biomarkers such as alpha-fetoprotein together with downstaging approaches and tumor evolution after enlistment has allowed the selection of patients most likely to benefit, resulting in 5-year survival rates greater that 70%. With the increasing use of immune checkpoint inhibitors (ICIs) across all stages of disease, alone or in combination with locoregional therapies, there is now the potential to further expand the patient population with HCC who may benefit from LT. This brings challenges, given the global shortage of organs and the need to better understand the optimal use of ICIs before transplantation. Furthermore, the field of transplant oncology awaits additional biomarkers that can predict those likely to benefit from ICIs. More than ever, a multidisciplinary approach for liver cancer management is critical to ensure all patients are considered for LT where appropriate, and do not miss the opportunity for long-term survival.

Current management of hepatobiliary malignancies between centers with or without a liver transplant program: A multi-society national survey

BACKGROUND

Availability of liver transplantation (LT) as a treatment for hepatocellular carcinoma (HCC) and other liver malignancies may determine heterogeneity of therapeutic strategies across different centers.

AIMS

To investigate the practice between hepato-biliary centers without (HB centers) and with a LT program (LT centers), we launched a 38-item web-based national survey, with directors of centers as a target.

METHODS

The survey, including 4 clinical vignettes, collected data on their approach to HCC and transplant oncology.

RESULTS

After duplicates removal, 75 respondents were considered. Respondents from LT centers (n = 22, 29.3 %) were more in favor of LT in the case of HCC outside Milan criteria (90.9 % vs. 67.9 %, p = 0.037), recurrent HCC (95.5 % vs. 50.9 %, p = 0.002) and other malignancies such as cholangiocarcinoma or neuroendocrine tumors. No significant difference was observed concerning the proportion of centers favorable to LT for unresectable colorectal liver metastases (100 % vs. 88.7 %, p = 0.100).

CONCLUSION

This national survey showed how management of HCC and awareness of transplant oncology may differ between HB and LT centers. Effective networking between HB and LT centers is crucial to provide optimal treatment and access to LT.

Validation of the R3-AFP model for risk prediction of HCC recurrence after liver transplantation in the SiLVER randomized clinical trial

Explant-based models for assessing HCC recurrence after liver transplantation serve as the gold standard, guiding post-liver transplantation screening and immunosuppression adjustment. Incorporating alpha-fetoprotein (AFP) levels into these models, such as the novel R3-AFP score, has notably enhanced risk stratification. However, validation of these models in high-evidence data is mandatory. Therefore, the aim of the present research was to validate the R3-AFP score in a randomized clinical trial. We analyzed the intention-to-treat population from the 2-arm SiLVER trial (NCT00355862), comparing calcineurin-based ([calcineurin inhibitors]-Group A) versus mammalian target of rapamycin inhibitors-based (sirolimus-Group B) immunosuppression for post-liver transplantation HCC recurrence. Competing risk analysis estimated sub-hazard ratios, with testing of discriminant function and calibration. Overall, 508 patients from the intention-to-treat analysis were included (Group A, n = 256; Group B, n = 252). The R3-AFP score distribution was as follows: 42.6% low-risk (n = 216), 35.7% intermediate-risk (n = 181), 19.5% high-risk (n = 99), and 2.2% very-high-risk (n = 11) groups. The R3-AFP score effectively stratified HCC recurrence risk, with increasing risk for each stratum. Calibration of the R3-AFP model significantly outperformed other explant-based models (Milan, Up-to-7, and RETREAT), whereas discrimination power (0.75 [95% CI: 0.69; 0.81]) surpassed these models, except for the RETREAT model ( p = 0.49). Subgroup analysis showed lower discrimination power in the mammalian target of rapamycin group versus the calcineurin inhibitors group ( p = 0.048). In conclusion, the R3-AFP score accurately predicted HCC recurrence using high-quality evidence-based data, exhibiting reduced performance under mammalian target of rapamycin immunosuppression. This highlights the need for further research to evaluate surveillance schedules and adjuvant regimens.

Expanding Selection Criteria in Deceased Donor Liver Transplantation for Hepatocellular Carcinoma: Long-term Follow-up of a National Registry and 2 Transplant Centers

BACKGROUND

This study compares selection criteria for liver transplant (LT) for hepatocellular carcinoma (HCC) for inclusivity and predictive ability to identify the most permissive criteria that maintain patient outcomes.

METHODS

The Scientific Registry of Transplant Recipients (SRTR) database was queried for deceased donor LT's for HCC (2003-2020) with 3-y follow-up; these data were compared with a 2-center experience. Milan, University of California, San Francisco (UCSF), 5-5-500, Up-to-seven (U7), HALT-HCC, and Metroticket 2.0 scores were calculated.

RESULTS

Nationally, 26 409 patients were included, and 547 at the 2 institutions. Median SRTR-follow-up was 6.8 y (interquartile range 3.9-10.1). Three criteria allowed the expansion of candidacy versus Milan: UCSF (7.7%, n = 1898), Metroticket 2.0 (4.2%, n = 1037), and U7 (3.5%, n = 828). The absolute difference in 3-y overall survival (OS) between scores was 1.5%. HALT-HCC (area under the curve [AUC] = 0.559, 0.551-0.567) best predicted 3-y OS although AUC was notably similar between criteria (0.506 < AUC < 0.527, Mila n = 0.513, UCSF = 0.506, 5-5-500 = 0.522, U7 = 0.511, HALT-HCC = 0.559, and Metroticket 2.0 = 0.520), as was Harrall's c-statistic (0.507 < c-statistic < 0.532). All scores predicted survival to P  < 0.001 on competing risk analysis. Median follow-up in our enterprise was 9.8 y (interquartile range 7.1-13.3). U7 (13.0%, n = 58), UCSF (11.1%, n = 50), HALT-HCC (6.4%, n = 29), and Metroticket 2.0 (6.3%, n = 28) allowed candidate expansion. HALT-HCC (AUC = 0.768, 0.713-0.823) and Metroticket 2.0 (AUC = 0.739, 0.677-0.801) were the most predictive of recurrence. All scores predicted recurrence and survival to P  < 0.001 using competing risk analysis.

CONCLUSIONS

Less restrictive criteria such as Metroticket 2.0, UCSF, or U7 allow broader application of transplants for HCC without sacrificing outcomes. Thus, the criteria for Model for End-stage Liver Disease-exception points for HCC should be expanded to allow more patients to receive life-saving transplantation.

Pembrolizumab in combination with LEnvatinib in participants with hepatocellular carcinoma before liver transplant as Neoadjuvant TherapY-PLENTY pilot study

BACKGROUND

The high recurrent rate after liver transplantation (LT) remains a clinical challenge, especially for those exceeding the Milan criteria (MC) and with high RETREAT scores. Therefore, the authors aim to investigate whether neoadjuvant systemic therapy allows safely administered and effectively reduces post-LT recurrence for those patients.

METHODS

In this prospective, randomized, open-label, pilot study, patients with HCC exceeding the MC were randomly assigned to PLENTY or control group before LT. The primary endpoint of the study was the recurrence-free survival after LT.

RESULTS

Twenty-two patients were enrolled and randomly assigned: 11 to the PLENTY group and 11 to the control group. The 30-month tumor-specific RFS was 37.5% in the PLENTY group and 12.5% in the control group. The 12-month tumor-specific RFS after LT was significantly improved in the PLENTY group (87.5%) compared to the control group (37.5%) ( P =0·0022). The objective response rate in the PLENTY group was 30 and 60% when determined by RECIST 1.1 and mRECIST, respectively. Six patients (60%) had significant tumor necrosis, including three (30%) who had complete tumor necrosis at histopathology. No acute allograft rejection after LT occurred in the PLENTY and Control group.

CONCLUSION

Neoadjuvant pembrolizumab plus lenvatinib before LT appears to be safe and feasible, associated with significantly better RFS for patients exceeding the MC. Despite the limitations of small sample size, this is the first RCT to evaluate neoadjuvant PD-1 blockade combined with tyrosine kinase inhibitors in LT recipients, the results of this study will inform future research.

Combined transarterial chemoembolization and thermal ablation in candidates to liver transplantation with hepatocellular carcinoma: pathological findings and post-transplant outcome

OBJECTIVES

Evaluating the pathological response and the survival outcomes of combined thermal ablation (TA) and transarterial chemoembolization (TACE) as a bridge or downstaging for liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) > 3 cm.

MATERIALS AND METHODS

A retrospective review encompassed 36 consecutive patients who underwent combined TA-TACE as bridging or downstaging before LT. Primary objectives included necrosis of the target lesion at explant pathology, post-LT overall survival (OS) and post-LT recurrence-free survival (RFS). For OS and RFS, a comparison with 170 patients subjected to TA alone for nodules <3 cm in size was also made.

RESULTS

Out of the 36 patients, 63.9% underwent TA-TACE as bridging, while 36.1% required downstaging. The average node size was 4.25 cm. All cases were discussed in a multidisciplinary tumor board to assess the best treatment for each patient. Half received radiofrequency (RF), and the other half underwent microwave (MW). All nodes underwent drug-eluting beads (DEB) TACE with epirubicin. The mean necrosis percentage was 65.9% in the RF+TACE group and 83.3% in the MW+TACE group (p-value = 0.099). OS was 100% at 1 year, 100% at 3 years and 94.7% at 5 years. RFS was 97.2% at 1 year, 94.4% at 3 years and 90% at 5 years. Despite the different sizes of the lesions, OS and RFS did not show significant differences with the cohort of patients subjected to TA alone.

CONCLUSIONS

The study highlights the effectiveness of combined TA-TACE for HCC>3 cm, particularly for bridging and downstaging to LT, achieving OS and RFS rates significantly exceeding 80% at 1, 3 and 5 years.

Downstaging of Hepatocellular Carcinoma Before Liver Transplantation: Current Advances in Selection Criteria and Therapeutic Options

Liver transplantation (LT) is an ideal therapeutic option for selected patients with hepatocellular carcinoma (HCC). The selection criteria of HCC for LT have evolved in recent decades. Downstaging therapy is a promising strategy for patients with tumor burden beyond transplant criteria to increase the chance of receiving LT and improve posttransplant survival. Downstaging therapy is also a selection tool that refines the conventional selection criteria based on tumor morphology. Recently, the success of systemic treatment, including immune checkpoint inhibitors, antiangiogenic tyrosine kinase inhibitors, and VEGF inhibitors, in advanced HCC has prompted the discussion regarding the role of systemic therapies for HCC downstaging before transplantation. In this review, we aimed to summarize the current advances in selection criteria and therapeutic options of downstaging therapy for HCC before LT.

Radiofrequency ablation combined with transcatheter arterial chemoembolization for recurrent liver cancer

BACKGROUND

The recurrence rate of liver cancer after surgery is high. Radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) is an effective treatment for liver cancer; however, its efficacy in recurrent liver cancer remains unclear.

AIM

To investigate the clinical effect of TACE combined with RFA in the treatment of recurrent liver cancer.

METHODS

Ninety patients with recurrent liver cancer were divided into 2 groups according to treatment plan: Control (RFA alone); and experimental [TACE combined with RFA (TACE + RFA)]. The incidence of increased alanine aminotransferase levels, complications, and other indices were compared between the two groups before and after the procedures.

RESULTS

One month after the procedures, the short-term efficacy rate and Karnofsky Performance Status scores of the experimental group were significantly higher than those of the control group (P < 0.05). Alpha-fetoprotein (AFP) and total bilirubin levels were lower than those in the control group (P < 0.05); The overall response rate was 82.22% and 66.67% in the experimental and control groups, respectively; The disease control rate was 93.33% and 82.22% in the experimental and control groups, respectively, the differences are statistically significant (P < 0.05). And there were no statistical differences in complications between the two groups (P > 0.05).

CONCLUSION

TACE + RFA was effective for the treatment of recurrent liver cancer and significantly reduced AFP levels and improved various indices of liver function.

The role of cold ischemia time and hypothermic perfusion in predicting early hepatocellular carcinoma recurrences after liver transplantation

AIM

The aim of the study was to identify predictors of early tumor recurrence in patients with hepatocellular carcinoma (HCC) after liver transplantation (LT).

METHODS

Retrospective cohort study in 237 consecutive liver recipients with HCC between 2016 and 2021. Multivariate logistic analysis was performed to identify predictors of early HCC recurrences. The impact of hypothermic-oxygenated perfusion (HOPE) on outcome was analyzed after propensity score weighting.

RESULTS

Early recurrences were observed in 15 cases. Microvascular invasion (OR 3.737, 95% CI 1.246-11.206, p = 0.019) and cold ischemia time (OR 1.155, 95% CI 1.001-1.333, p = 0.049) were independently associated with a lower risk of HCC recurrences. After balancing for relevant variables, patients in the HOPE group had lower rates of tumor recurrence (weighted OR 0.126, 95% CI 0.016-0.989, p = 0.049) and higher recurrence free survival (weighted HR 0.132, 95% CI 0.017-0.999, p = 0.050).

CONCLUSION

Reducing cold ischemia time and graft perfusion with HOPE can lead to lower rates of early HCC recurrences and higher recurrence-free survival.

From evidence to clinical practice: Bridging the gap of new liver cancer therapies in Latin America

The most common primary liver tumors are hepatocellular carcinoma and cholangiocarcinoma. They constitute the sixth most common neoplasia and the third cause of cancer-related deaths worldwide. Although both tumors may share etiologic factors, diagnosis, prognostic factors, and treatments, they differ substantially in determining distinctive clinical management. In recent years, significant advances have been made in the management of these neoplasms, particularly in advanced stages. In this review, we focus on the most relevant diagnostic, prognostic, and treatment aspects of both, hepatocellular carcinoma and cholangiocarcinoma, underlying their applicability in Latin America.

Risk assessment in liver transplantation for hepatocellular carcinoma: long-term follow-up of a two-centre experience

BACKGROUND

Liver transplantation (LT) is a well-established treatment for hepatocellular carcinoma (HCC), but there are ongoing debates regarding outcomes and selection. This study examines the experience of LT for HCC at a high-volume centre.

METHODS

A prospectively maintained database was used to identify HCC patients undergoing LT from 2000 to 2020 with more than or equal to 3-years follow-up. Data were obtained from the centre database and electronic medical records. The Metroticket 2.0 HCC-specific 5-year survival scale was calculated for each patient. Kaplan-Meier and Cox-regression analyses were employed assessing survival between groups based on Metroticket score and individual donor and recipient risk factors.

RESULTS

Five hundred sixty-nine patients met criteria. Median follow-up was 96.2 months (8.12 years; interquartile range 59.9-147.8). Three-year recurrence-free (RFS) and overall survival (OS) were 88.6% ( n =504) and 86.6% ( n =493). Five-year RFS and OS were 78.9% ( n =449) and 79.1% ( n =450). Median Metroticket 2.0 score was 0.9 (interquartile range 0.9-0.95). Tumour size greater than 3 cm ( P =0.012), increasing tumour number on imaging ( P =0.001) and explant pathology ( P <0.001) was associated with recurrence. Transplant within Milan ( P <0.001) or UCSF criteria ( P <0.001) had lower recurrence rates. Increasing alpha-fetoprotein (AFP)-values were associated with more HCC recurrence ( P <0.001) and reduced OS ( P =0.008). Chemoembolization was predictive of recurrence in the overall population ( P =0.043) and in those outside-Milan criteria ( P =0.038). A receiver-operator curve using Metroticket 2.0 identified an optimal cut-off of projected survival greater than or equal to 87.5% for predicting recurrence. This cut-off was able to predict RFS ( P <0.001) in the total cohort and predict both, RFS ( P =0.007) and OS ( P =0.016) outside Milan. Receipt of donation after brain death (DBD) grafts (55/478, 13%) or living-donor grafts (3/22, 13.6%) experienced better survival rates compared to donation after cardiac death (DCD) grafts ( n =15/58, 25.6%, P =0.009). Donor age was associated with a higher HCC recurrence ( P =0.006). Both total ischaemia time (TIT) greater than 6hours ( P =0.016) and increasing TIT correlated with higher HCC recurrence ( P =0.027). The use of DCD grafts for outside-Milan candidates was associated with increased recurrence ( P =0.039) and reduced survival ( P =0.033).

CONCLUSION

This large two-centre analysis confirms favourable outcomes after LT for HCC. Tumour size and number, pre-transplant AFP, and Milan criteria remain important recipient HCC-risk factors. A higher donor risk (i.e. donor age, DCD grafts, ischaemia time) was associated with poorer outcomes.

A refined prediction model for survival in hepatocellular carcinoma patients treated with transarterial chemoembolization

Background/Aims

Transarterial chemoembolization (TACE) is widely performed as a major treatment for hepatocellular carcinoma (HCC) patients, and there is a need to stratify patients for whom the most benefit from the treatment. This study aimed to develop a refined prediction model for overall survival (OS) in patients undergoing TACE as a first-line treatment in a large cohort and validate its performance.

Methods

A total of 2,632 patients with HCC of Barcelona Clinic Liver Cancer stage A or B who underwent TACE between 2008 and 2017 were enrolled. The patients were randomly assigned to a training cohort (n = 1,304) or a validation cohort (n = 1,328). Independent predictors of OS were used to develop a prediction model.

Results

The median age of patients in the entire cohort was 63 years, with the majority having hepatitis B virus (56.6%) and being classified as Child-Pugh class A (82.4%). We developed a new prognostic model, called the TACE-prognostic (TP) score, based on tumor burden (sum of the largest tumor diameter and tumor number), alpha-fetoprotein, and Albumin-Bilirubin grade. Patients were classified into five risk groups according to TP scores, with median survival significantly differentiated in both training and validation cohorts (P < 0.001). The new model consistently outperformed other currently available models in both the training and validation cohorts.

Conclusion

This newly developed TP scoring system has the potential to be a useful tool in identifying ideal candidates of TACE and predicting OS with favorable performance and discrimination. However, further external validation is needed to confirm its effectiveness.

Impact of Pre-Liver Transplant Treatments on the Imaging Accuracy of HCC Staging and Their Influence on Outcomes

The outcome of liver transplantation (LT) for hepatocarcinoma (HCC) is strongly influenced by HCC staging, which is based on radiological examinations in a pre-LT setting; concordance between pre-LT radiological and definitive pathological staging remains controversial. To address this issue, we retrospectively analyzed our LT series to assess concordance between radiology and pathology and to explore the factors associated with poor concordance and outcomes. We included all LTs with an HCC diagnosis performed between 2013 and 2018. Concordance (Co group) was defined as a comparable tumor burden in preoperative imaging and post-transplant pathology; otherwise, non-concordance was diagnosed (nCo group). Concordance between radiology and pathology was observed in 32/134 patients (Co group, 24%). The number and diameter of the nodules were higher when nCo was diagnosed, as was the number of pre-LT treatments. Although concordance did not affect survival, more than three pre-LT treatments led to a lower disease-free survival. Patients who met the Milan Criteria (Milan-in patients) were more likely to receive ≥three prior treatments, leading to a lower survival in multi-treated Milan-in patients than in other Milan-in patients. In conclusion, the concordance rate between the pre-LT imaging and histopathological results was low in patients with a high number of nodules. Multiple bridging therapies reduce the accuracy of pre-LT imaging in predicting HCC stages and negatively affect outcomes after LT.

A Deep Learning Model Combining Multimodal Factors to Predict the Overall Survival of Transarterial Chemoembolization

Background

To develop and validate an overall survival (OS) prediction model for transarterial chemoembolization (TACE).

Methods

In this retrospective study, 301 patients with hepatocellular carcinoma (HCC) who received TACE from 2012 to 2015 were collected. The residual network was used to extract prognostic information from CT images, which was then combined with the clinical factors adjusted by COX regression to predict survival using a modified deep learning model (DLOPCombin). The DLOPCombin model was compared with the residual network model (DLOPCTR), multiple COX regression model (DLOPCox), Radiomic model (Radiomic), and clinical model.

Results

In the validation cohort, DLOPCombin shows the highest TD AUC of all cohorts, which compared with Radiomic (TD AUC: 0.96vs 0.63) and clinical model (TD AUC: 0.96 vs 0.62) model. DLOPCombin showed significant difference in C index compared with DLOPCTR and DLOPCox models (P < 0.05). Moreover, the DLOPCombin showed good calibration and overall net benefit. Patients with DLOPCombin model score ≤ 0.902 had better OS (33 months vs 15.5 months, P < 0.0001).

Conclusion

The deep learning model can effectively predict the patients' overall survival of TACE.

Liver transplantation meets gastrointestinal cancer

Liver transplantation (LT) has emerged as a standard of care for patients with end-stage liver disease, providing a life-saving intervention for patients with severely compromised liver function in both the acute and chronic setting. While LT has also become a routine procedure for early-stage hepatocellular carcinoma (HCC), offering a potential cure by treating both the tumor and the underlying liver disease, its relevance in the context of other malignancies such as cholangiocellular carcinoma (CCA), combined hepatocellular-cholangiocarcinoma (cHCC-CCA) or liver metastases is still the subject of intense debate and no definite recommendations have yet been established. This review summarizes the current therapeutic standards in the context of LT for gastrointestinal malignancies and provides a reflection and outlook on current scientific and clinical developments.

Hepatocellular Carcinoma: Optimal Radiological Evaluation before Liver Transplantation

Liver transplantation (LT) is the recommended curative-intent treatment for patients with early or intermediate-stage hepatocellular carcinoma (HCC) who are ineligible for resection. Imaging plays a central role in staging and for selecting the best LT candidates. This review will discuss recent developments in pre-LT imaging assessment, in particular LT eligibility criteria on imaging, the technical requirements and the diagnostic performance of imaging for the pre-LT diagnosis of HCC including the recent Liver Imaging Reporting and Data System (LI-RADS) criteria, the evaluation of the response to locoregional therapy, as well as the non-invasive prediction of HCC aggressiveness and its impact on the outcome of LT. We will also briefly discuss the role of nuclear medicine in the pre-LT evaluation and the emerging role of artificial intelligence models in patients with HCC.

Quantitative Prediction of Posttransplant Hepatocellular Carcinoma Prognosis Using ADV Score: Validation with Korea-Nationwide Transplantation Registry Database

OBJECTIVE

The aim of this study is to validate the prognostic impact of ADV score (α-fetoprotein [AFP]-des-γ-carboxyprothrombin [DCP]-tumor volume [TV] score) for predicting prognosis of hepatocellular carcinoma (HCC) following liver transplantation (LT).

BACKGROUND

ADV score has been reported as a prognostic surrogate biomarker of HCC following LT and hepatectomy.

METHODS

The study patients were 1599 LT recipients selected from the Korean Organ Transplantation Registry database.

RESULTS

Deceased-donor and living-donor LTs were performed in 143 and 1456 cases, respectively. Weak correlation was present among AFP, DCP, and TV. The viable HCC group showed ADV score-dependent disease-free survival (DFS) and overall patient survival (OS) rates from 1log to 10log (p<0.001). Prognosis of complete pathological response group was comparable to that of ADV score <1log (p≥0.099). ADV score cutoff of 5log (ADV-5log) for DFS and OS was obtained through receiver operating characteristic curve analysis with area under the curve ≥0.705. Both ADV-5log and Milan criteria were independent risk factors for DFS and OS, and their prognostic impacts were comparable to each other. Combination of these two factors resulted in further prognostic stratification, showing hazard ratios for DFS and OS as 2.98 and 2.26 respectively for one risk factor and 7.92 and 8.19 respectively for two risk factors (p<0.001). ABO-incompatible recipients with ADV score ≥8log or two risk factors showed higher recurrence rates.

CONCLUSIONS

This validation study revealed that ADV score is a reliable surrogate biomarker for posttransplant HCC prognosis, which can be used for selecting LT candidates and guiding risk-based posttransplant follow-up surveillance.

Cell-Free DNA as a Surveillance Tool for Hepatocellular Carcinoma Patients after Liver Transplant

The liver is the world's sixth most common primary tumor site, responsible for approximately 5% of all cancers and over 8% of cancer-related deaths. Hepatocellular carcinoma (HCC) is the predominant type of liver cancer, accounting for approximately 75% of all primary liver tumors. A major therapeutic tool for this disease is liver transplantation. Two of the most significant issues in treating HCC are tumor recurrence and graft rejection. Currently, the detection and monitoring of HCC recurrence and graft rejection mainly consist of imaging methods, tissue biopsies, and alpha-fetoprotein (AFP) follow-up. However, they have limited accuracy and precision. One of the many possible components of cfDNA is circulating tumor DNA (ctDNA), which is cfDNA derived from tumor cells. Another important component in transplantation is donor-derived cfDNA (dd-cfDNA), derived from donor tissue. All the components of cfDNA can be analyzed in blood samples as liquid biopsies. These can play a role in determining prognosis, tumor recurrence, and graft rejection, assisting in an overall manner in clinical decision-making in the treatment of HCC.

The predictive value of the modified AFP model for liver transplantation outcomes in multinodular hepatocellular carcinoma patients

BACKGROUND

There is a lack of studies focusing on the benefit of liver transplantation (LT) in hepatocellular carcinoma (HCC) patients with > 3 tumors. This study aims to establish a model to effectively predict overall survival in Chinese HCC patients with multiple tumors (> 3 tumors) who undergo LT.

METHODS

This retrospective study included 434 HCC liver transplant recipients from the China Liver Transplant Registry. All HCC patients had more than 3 tumor nodules. Three selection criteria systems (i.e., AFP, Metroticket 2.0, and Up-to-7) were compared regarding the prediction of HCC recurrence. The modified AFP model was established by univariate and multivariate competing risk analyses.

RESULTS

The AFP score 2 and the AFP score ≥ 3 groups had 5-year recurrence rates of 19.6% and 40.5% in our cohort. The prediction of HCC recurrence based on the AFP model was associated with a c-statistic of 0.606, which was superior to the Up-to-7 and Metroticket 2.0 models. AFP level > 1000 ng/mL, largest tumor size ≥ 8 cm, vascular invasion, and MELD score ≥ 15 were associated with overall survival. The 5-year survival rate in the modified AFP score 0 group was 71.7%.

CONCLUSIONS

The AFP model is superior in predicting tumor recurrence in HCC patients with > 3 tumors prior to LT. With the modified AFP model, patients likely to derive sufficient benefit from LT can be identified.

Main factors influencing long-term outcomes of liver transplantation in 2022

Liver transplant (LT) outcomes have markedly improved in the recent decades, even if long-term morbidity and mortality are still considerable. Most of late deaths are independent from graft function and different comorbidities, including complications of metabolic syndrome and de novo neoplasms, seem to play a key role in determining long-term outcomes in LT recipients. This review discusses the main factors associated with late mortality and suggests possible strategies to improve long-term management and follow-up after liver transplantation. In particular, the reduction of drug toxicity, the use of tools to identify high-risk patients, and setting up a multidisciplinary team also for long-term management of LT recipients may further improve survival after liver transplantation.

Textbook Outcome After Trans-arterial Chemoembolization for Hepatocellular Carcinoma

PURPOSE

Textbook Outcome (TO) is inclusive of quality indicators and it not been provided for trans-arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Data on treatment-naïve HCC patients receiving TACE from 10 centers were reviewed. TO was defined as "no post-TACE grade 3-4 complications, no prolonged hospital stay (defined as a post-procedure stay ≤ 75th percentile of the median values from the total cohort), no 30-day mortality/readmission and the achievement of an objective response (OR) at post-TACE imaging." Grade of adverse event was classified according to the Common Terminology Criteria for Adverse Events and short-term efficacy was assessed by response. Pooled estimates were calculated to account for hospital's effect and risk-adjustment was applied to allow for diversity of patients in each center.

RESULTS

A total of 1124 patients (2014-2018) fulfilling specific inclusion criteria were included. Baseline clinical features showed considerable heterogeneity (I² > 0.75) across centers. TACE-related mortality was absent in 97.6%, readmission was not required after 94.9% of procedures, 91.5% of patients had no complication graded 3-4, 71.8% of patients did not require prolonged hospitalization, OR of the target lesion was achieved in 68.5%. Risk-adjustment showed that all indicators were achieved in 43.1% of patients, and this figure was similar across centers. The median overall survival for patients who achieved all indicators was 33.1 months, 11.9 months longer than for patients who did not.

CONCLUSIONS

A useful benchmark for TACE in HCC patients has been developed, which provides an indication of survival and allows for a comparison of treatment quality across different hospitals.

AFP score and metroticket 2.0 perform similarly and could be used in a "within-ALL" clinical decision tool

BACKGROUND & AIMS

Two recently developed composite models, the alpha-fetoprotein (AFP) score and Metroticket 2.0, could be used to select patients with hepatocellular carcinoma (HCC) who are candidates for liver transplantation (LT). The aim of this study was to compare the predictive performance of both models and to evaluate the net risk reclassification of post-LT recurrence between them using each model's original thresholds.

METHODS

This multicenter cohort study included 2,444 adult patients who underwent LT for HCC in 47 centers from Europe and Latin America. A competing risk regression analysis estimating sub-distribution hazard ratios (SHRs) and 95% CIs for recurrence was used (Fine and Gray method). Harrell's adapted c-statistics were estimated. The net reclassification index for recurrence was compared based on each model's original thresholds.

RESULTS

During a median follow-up of 3.8 years, there were 310 recurrences and 496 competing events (20.3%). Both models predicted recurrence, HCC survival and survival better than Milan criteria (p <0.0001). At last tumor reassessment before LT, c-statistics did not significantly differ between the two composite models, either as original or threshold versions, for recurrence (0.72 vs. 0.68; p = 0.06), HCC survival, and overall survival after LT. We observed predictive gaps and overlaps between the model's thresholds, and no significant gain on reclassification. Patients meeting both models ("within-ALL") at last tumor reassessment presented the lowest 5-year cumulative incidence of HCC recurrence (7.7%; 95% CI 5.1-11.5) and higher 5-year post-LT survival (70.0%; 95% CI 64.9-74.6).

CONCLUSIONS

In this multicenter cohort, Metroticket 2.0 and the AFP score demonstrated a similar ability to predict HCC recurrence post-LT. The combination of these composite models might be a promising clinical approach.

IMPACT AND IMPLICATIONS

Composite models were recently proposed for the selection of liver transplant (LT) candidates among individuals with hepatocellular carcinoma (HCC). We found that both the AFP score and Metroticket 2.0 predicted post-LT HCC recurrence and survival better than Milan criteria; the Metroticket 2.0 did not result in better reclassification for transplant selection compared to the AFP score, with predictive gaps and overlaps between the two models; patients who met low-risk thresholds for both models had the lowest 5-year recurrence rate. We propose prospectively testing the combination of both models, to further optimize the LT selection process for candidates with HCC.

Long-term Outcomes of Patients with Hepatocellular Carcinoma Who Underwent Microwave Ablation after Downstaging with Transarterial Chemoembolization to Barcelona Clinic Liver Cancer Stage A

PURPOSE

To compare the clinical results of microwave ablation (MWA) between patients downstaged to Barcelona Clinic Liver Cancer (BCLC) Stage A with transarterial chemoembolization (TACE) and those initially classified as BCLC Stage A.

MATERIALS AND METHODS

From January 2012 to May 2017, 1,087 patients were reviewed retrospectively using propensity score matching (1:1): 86 patients underwent MWA as a curative treatment after downstaging to BCLC Stage A by TACE (downstaging group) and 86 patients initially classified as BCLC Stage A underwent MWA (control group). The overall survival (OS) and disease-free survival (DFS) between the 2 groups were compared.

RESULTS

The 1-, 3-, and 5-year OS rates were 95.3%, 79.1%, and 58.1%, respectively, in the downstaging group and 93.0%, 81.4%, and 61.6%, respectively, in the control group (hazard ratio [HR], 0.75; 95% CI, 0.50-1.13; P = .162). The 1-, 3-, and 5-year DFS rates were 80.2%, 50.0%, and 24.4%, respectively, in the downstaging group and 77.9%, 52.3%, and 27.9%, respectively, in the control group (HR, 1.08; 95% CI, 0.76-1.53; P = .678). No significant differences were found in OS and DFS.

CONCLUSIONS

The long-term prognosis in patients with HCC who underwent MWA after downstaging to BCLC Stage A using TACE was similar to that in patients with initial BCLC Stage A.

Expert Insights on Current Treatments for Hepatocellular Carcinoma: Clinical and Molecular Approaches and Bottlenecks to Progress

Hepatocellular carcinoma (HCC) is a primary liver tumor that typically occurs in the setting of chronic liver disease/cirrhosis. Treatment modalities for HCC have evolved and given the variety of treatment options, a multi-disciplinary approach requiring input from surgical, medical, and radiation oncology, hepatology, and interventional radiology is necessary. Multiple advances have been made over the last decade regarding treatment of HCC, especially advanced disease. Resection and transplantation remain as cornerstone curative-intent treatment options. For patients who are not candidates for curative-intent therapy, exciting progress has been made in molecular and cellular approaches to systemic therapy for HCC including immunotherapies and tyrosine kinase inhibitors. Although the prognosis for advanced HCC remains poor, the armamentarium of therapies has increased, and valuable years of life can be gained with these therapies. While the main therapeutic modality for early-stage disease remains resection, multimodal immunotherapy has emerged as first-line treatment for advanced disease. We herein review different clinical and molecular treatment modalities related to the treatment of HCC, as well as provide insights into future directions for HCC treatment. We highlight how research and progress are needed to move into a new era of molecular and cellular treatments.

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.

Outcomes after primary and repeat thermal ablation of hepatocellular carcinoma with or without liver transplantation

OBJECTIVES

Thermal ablation (TA) is an established treatment for early HCC. There is a lack of data on the efficacy of repeated TA for recurrent HCC, resulting in uncertainty whether good oncologic outcomes can be obtained without performing orthotopic liver transplantation (OLTx). This study analyses outcomes after TA, with a special focus on repeat TA for recurrent HCC, either as a stand-alone therapy, or in relationship with OLTx.

METHODS

Data from a prospectively registered database on interventions for HCC in a tertiary hepatobiliary centre was completed with follow-up until December 2020. Outcomes studied were rate of recurrence after primary TA and after its repeat interventions, the occurrence of untreatable recurrence, OS and DSS after primary and repeat TA, and complications after TA. In cohorts matched for confounders, OSS and DSS were compared after TA with and without the intention to perform OLTx.

RESULTS

After TA, 100 patients (56·8%) developed recurrent HCC, of whom 76 (76·0%) underwent up to four repeat interventions. During follow-up, 76·7% of patients never developed a recurrence unamenable to repeat TA or OLTx. OS was comparable after primary TA and repeat TA. In matched cohorts, OS and DSS were comparable after TA with and without the intention to perform OLTx.

CONCLUSIONS

We found TA to be an effective and repeatable therapy for primary and recurrent HCC. Most recurrences can be treated with curative intent. There are patients who do well with TA alone without ever undergoing OLTx.

KEY POINTS

• Recurrent HCC after primary TA can often be treated effectively with repeat TA. Survival after repeat TA is comparable to primary TA. • In matched cohorts, outcomes after TA with and without subsequent waitlisting for OLTx are comparable. • There are patients who do well for many years with primary and repeat TA alone; some despite multiple recurrences.

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.

Patient Selection for Downstaging of Hepatocellular Carcinoma Prior to Liver Transplantation—Adjusting the Odds?

Background and Aims: Morphometric features such as the Milan criteria serve as standard criteria for liver transplantation (LT) in patients with hepatocellular carcinoma (HCC). Since it has been recognized that these criteria are too restrictive and do not adequately display the tumor biology, additional selection parameters are emerging.

Methods: Concise review of the current literature on patient selection for downstaging and LT for HCC outside the Milan criteria.

Results: The major task in patients outside the Milan criteria is the need for higher granularity with patient selection, since the benefit through LT is not uniform. The recent literature clearly shows that beneath tumor size and number, additional selection parameters are useful in the process of patient selection for and during downstaging. For initial patient selection, the alpha fetoprotein (AFP) level adds additional information to the size and number of HCC nodules concerning the chance of successful downstaging and LT. This effect is quantifiable using newer selection tools like the WE (West-Eastern) downstaging criteria or the Metroticket 2.0 criteria. Also an initial PET-scan and/or tumor biopsy can be helpful, especially in the high risk group of patients outside the University of California San Francisco (UCSF) criteria. After this entry selection, the clinical course during downstaging procedures concerning the tumor and the AFP response is of paramount importance and serves as an additional final selection tool.

Conclusion: Selection criteria for liver transplantation in HCC patients are becoming more and more sophisticated, but are still imperfect. The implementation of molecular knowledge will hopefully support a more specific risk prediction for HCC patients in the future, but do not provide a profound basis for clinical decision-making at present.

Anticancer Effect of Statins in Patients Undergoing Liver Transplantation for Hepatocellular Carcinoma

The anticancer effect of statins is drawing attention. However, it is unclear whether statin use reduces the risk of hepatocellular carcinoma (HCC) recurrence in patients who undergo liver transplantation (LT) for HCC. Consecutive patients who underwent LT for HCC between 1995 and 2019 were enrolled. The effects of statins on HCC recurrence and mortality were compared between statin user and statin nonuser groups. We performed the analyses in a variety of ways, including inverse probability treatment weighting (IPTW) methods to balance any confounders and the landmark method to avoid immortal time bias. A total of 430 patients were enrolled, among whom 323 (75.1%) were statin nonusers and 107 (24.9%) were statin users. During a median of 64.9 months (IQR, 26.1-122.6 months) of follow-up, 79 patients (18.4%) had HCC recurrence and 111 (25.8%) died. Among those who died, 53 (47.7%) were identified as HCC-related mortalities. Statin use was a predictor of HCC recurrence (adjusted hazard ratio [HR], 0.3; 95% confidence interval [CI], 0.1-0.6; P = 0.002), all-cause mortality (adjusted HR, 0.3; 95% CI, 0.2-0.5; P < 0.001), and HCC-related mortality (adjusted HR, 0.4; 95% CI, 0.2-0.9; P = 0.03). The effects of statin use on clinical outcomes were also identified through IPTW analysis. There was a dose-dependent relationship between statin use and HCC recurrence. The anticancer effect of statins on HCC recurrence was consistently significant across multivariable-stratified and sensitivity analyses. Statin use significantly reduced the risk of HCC recurrence and improved the survival of patients who underwent LT for HCC.

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.

The Landscape Of Alpha Fetoprotein In Hepatocellular Carcinoma: Where Are We?

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has been acknowledged as a leading cause of death among cirrhosis patients. Difficulties in early diagnosis and heterogeneity are obstacles to effective treatment, especially for advanced HCC. Liver transplantation (LT) is considered the best therapy for HCC. Although many biomarkers are being proposed, alpha-fetoprotein (AFP), which was identified over 60 years ago, remains the most utilized. Recently, much hope has been placed in the immunogenicity of AFP to develop novel therapies, such as AFP vaccines and AFP-specific adoptive T-cell transfer (ACT). This review summarizes the performance of AFP as a biomarker for HCC diagnosis and prognosis, as well as its correlation with molecular classes. In addition, the role of AFP in LT is also described. Finally, we highlight the mechanism and application prospects of two immune therapies (AFP vaccine and ACT) for HCC. In general, our review points out the prevalence of AFP in HCC, accompanied by some controversies and novel directions for future research.

Prognostic role of selection criteria for liver transplantation in patients with hepatocellular carcinoma: a network meta-analysis

BACKGROUND

Patients with hepatocellular carcinoma (HCC) are selected for transplantation if they have a low tumour burden and low risk of recurrence. The morphometric Milan criteria have been the cornerstone for patient selection, but dynamic morphological and biological tumour characteristics surfaced as an encouraging tool to refine the selection of patients with HCC and to support the expansion of the Milan criteria. The outcomes of the most prevalent models that select patients with HCC for liver transplantation were analysed in this study, which aimed to identify the selection model that offered the best recurrence-free and overall survival after transplantation.

METHODS

Studies that compared Milan, University of California San Francisco (UCSF), up-to-seven (UPTS), alpha-fetoprotein (AFP), and MetroTicket 2.0 (MT2) models were included. One-year, 3-year, and 5-year recurrence-free and overall survival rates of patients selected for transplantation using different models were analysed.

RESULTS

A total of 60 850 adult patients with HCC selected for liver transplantation using Milan, UCSF, UPTS, AFP, or MT2 criteria were included. Patients selected for transplantation using the MT2 model had the highest 1-, 3-, and 5-year recurrence-free survival. In addition, patients selected for transplantation using MT2 criteria had the best 1- and 3-year overall survival, whereas patients selected for transplantation using the Milan criteria had the best 5-year overall survival rates.

CONCLUSION

The MT2 model offered the best post-transplant outcomes in patients with HCC, highlighting the importance of considering tumour morphology and biology when selecting patients with HCC for liver transplantation.

Models to Predict Development or Recurence of Hepatocellular Carcinoma (HCC) in Patients with Advanced Hepatic Fibrosis

PURPOSE OF REVIEW

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death in the United States (U.S.).1 The purpose of this review is to highlight published models that predict development of HCC and estimate risk of HCC recurrence after treatments.

RECENT FINDINGS

There have been several models created for both de novo HCC and HCC recurrence, with the more recent models using a combination of age, sex, decompensation, and laboratory values (platelet count, albumin, bilirubin), and liver disease etiology to predict both 5 and 10-year HCC incidence. For chronic hepatitis C, sustained virologic response has been a useful component of understanding HCC risk reduction. BMI and diabetes have been utilized in non-alcoholic fatty liver disease (NAFLD) models to predict HCC risk. For HCC recurrence after treatment (for both surgical resection and liver transplant), tumor size and number, vascular invasion, alpha-fetoprotein (AFP) and neutrophil to lymphocyte ratio (NLR) are all components of HCC recurrence risk models. Although numerous HCC risk prediction models have been established over the last several years, challenges remain including how to best incorporate these models into clinical practice, improve surveillance for NAFLD-HCC development, and determine timing and duration of post-resection recurrence surveillance.

Deceased Donor Liver Transplantation After Radioembolization for Hepatocellular Carcinoma and Portal Vein Tumoral Thrombosis: A Pilot Study

Hepatocellular carcinoma (HCC) with portal vein tumoral thrombosis (PVTT) represents a major concern especially in the field of deceased donor liver transplantation (DDLT). However, when receiving transarterial radioembolization (TARE), a considerable percentage of such patients are able to achieve a radiologic complete response with adequate survival rates. In this pilot prospective study, we evaluated the effect of TARE in downstaging HCC patients with PVTT to meet criteria for DDLT. Between May 2013 and November 2016, patients were evaluated to be enrolled into our "Superdownstaging" protocol. Patients received yttrium-90 TARE and were enlisted for DDLT in case of complete and sustained (6 months) radiological response. Patients with tumor thrombus in the main trunk and/or in the contralateral portal vein branch were excluded. TARE was effective in downstaging and receiving DDLT in 5/17 patients (29.4%). The 5-year overall survival was significantly higher in patients who underwent DDLT compared with those who were not transplanted (60.0% versus 0.0%, P = 0.03). Three out of 5 patients developed recurrence within 1 year after LT. The current series showed a clear survival gain in those patients who were able to receive DDLT after TARE but careful selection for DDLT is however advised.

Pre-Transplant Alpha-Fetoprotein > 25.5 and Its Dynamic on Waitlist Are Predictors of HCC Recurrence after Liver Transplantation for Patients Meeting Milan Criteria

BACKGROUND AND AIM

Hepatocellular carcinoma (HCC) recurrence rates after liver transplantation (LT) range between 8 and 20%. Alpha-fetoprotein (AFP) levels at transplant can predict HCC recurrence, however a defined cut-off value is needed to better stratify patients. The aim of this study was to evaluate the rate of HCC recurrence at our centre and to identify predictors, focusing on AFP.

METHODS

We retrospectively analysed 236 consecutive patients that were waitlisted for HCC who all met the Milan criteria from January 2001 to December 2017 at our liver transplant centre. A total of twenty-nine patients dropped out while they were waitlisted, and 207 patients were included in the final analysis. All survival analyses included the competing-risk model.

RESULTS

The mean age was 56.8 ± 6.8 years. A total of 14% were female (n = 29/207). The median MELD (model for end-stage liver disease) at LT was 12 (9-16). The median time on the waitlist was 92 (41-170) days. The HCC recurrence rate was 16.4% (n = 34/208). The mean time to recurrence was 3.3 ± 2.8 years. The median AFP levels at transplant were higher in patients with HCC recurrence (p < 0.001). At multivariate analysis, the AFP value at transplant that was greater than 25.5 ng/mL (AUC 0.69) was a strong predictor of HCC recurrence after LT [sHR 3.3 (1.6-6.81); p = 0.001]. The HCC cumulative incidence function (CIF) of recurrence at 10 years from LT was significantly higher in patients with AFP > 25.5 ng/mL [34.3% vs. 11.5% (p = 0.001)]. Moreover, an increase in AFP > 20.8%, was significantly associated with HCC recurrence (p = 0.034).

CONCLUSIONS

In conclusion, in our retrospective study, the AFP level at transplant > 25.5 ng/mL and its increase greater than 20.8% on the waitlist were strong predictors of HCC recurrence after LT in a cohort of patients that were waitlisted within the Milan criteria. However further studies are needed to validate these data.

Artificial Intelligence in Liver Transplantation

BACKGROUND

Advancements based on artificial intelligence have emerged in all areas of medicine. Many decisions in organ transplantation can now potentially be addressed in a more precise manner with the aid of artificial intelligence.

METHOD/RESULTS

All elements of liver transplantation consist of a set of input variables and a set of output variables. Artificial intelligence identifies relationships between the input variables; that is, how they select the data groups to train patterns and how they can predict the potential outcomes of the output variables. The most widely used classifiers to address the different aspects of liver transplantation are artificial neural networks, decision tree classifiers, random forest, and naïve Bayes classification models. Artificial intelligence applications are being evaluated in liver transplantation, especially in organ allocation, donor-recipient matching, survival prediction analysis, and transplant oncology.

CONCLUSION

In the years to come, deep learning-based models will be used by liver transplant experts to support their decisions, especially in areas where securing equitability in the transplant process needs to be optimized.

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.

Management of Hepatocellular Carcinoma Recurrence after Liver Transplantation

Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT), occurring in 10-15% of cases, is a major concern. A lot of work has been done in order to refine the selection of LT candidates with HCC and to improve the outcome of patients with recurrence. Despite this, the prognosis of these patients remains poor, partly due to the several areas of uncertainty in their management. Even if surveillance for HCC recurrence is crucial for early detection, there is currently no evidence to support a specific and cost-effective post-LT surveillance strategy. Concerning preventive measures, consensus on the best immunosuppressive drugs has not been reached and not enough data to support adjuvant therapy are present. Several therapeutic approaches (surgical, locoregional and systemic treatments) are available in case of recurrence, but there are still few data in the post-LT setting. Moreover, the use of immune checkpoint inhibitors is controversial in transplant recipients considered the risk of rejection. In this paper, the available evidence on the management of HCC recurrence after LT is comprehensively reviewed, considering pre- and post-transplant risk stratification, post-transplant surveillance, preventive strategies and treatment options.

Prognostic significance of viable tumor size measurement in hepatocellular carcinomas after preoperative locoregional treatment

Background

Preoperative locoregional treatment (LRT) for hepatocellular carcinoma (HCC) often induces intratumoral necrosis without affecting the overall tumor size, and residual viable tumor size (VTS) on imaging is an important clinical parameter for assessing post-treatment response. However, for surgical specimens, it is unclear whether the VTS would be more relevant to prognosis compared to total tumor size (TTS).

Methods

A total of 142 surgically resected solitary HCC cases were retrospectively reviewed. The TTS and VTS were assessed by applying the modified Response Evaluation Criteria in Solid Tumors method to the resected specimens, and correlated with the clinicopathological features and survival.

Results

As applying VTS, 13/142 cases (9.2%) were down-staged to ypT1a. Although the survival analysis results for overall survival according to TTS or VTS were similar, VTS was superior to predict disease-free survival (DFS; p = .023) compared to TTS (p = .08). In addition, multivariate analysis demonstrated VTS > 2 cm to be an independent predictive factor for decreased DFS (p = .001). In the subpopulation of patients with LRT (n = 54), DFS in HCCs with TTS or VTS > 2 cm were significantly shorter than those with TTS or VTS ≤ 2 cm (p = .047 and p = .001, respectively). Interestingly, HCCs with TTS > 2 cm but down-staged to VTS ≤ 2 cm after preoperative LRT had similar survival to those with TTS ≤ 2 cm.

Conclusions

Although the prognostic impact of tumor size was similar regardless of whether TTS or VTS was applied, reporting VTS may help to increase the number of candidates for surgery in HCC patients with preoperative LRT.

A retrospective single-centre analysis of the oncological impact of LI-RADS classification applied to Metroticket 2.0 calculator in liver transplantation: every nodule matters

Although the diagnostic value of Liver Imaging Reporting and Data System (LI-RADS) protocol is well recognized in clinical practice, its role in liver transplant (LT) setting is under-explored. We sought to evaluate the oncological impact of LI-RADS classification applied to Metroticket 2.0 calculator in a single-centre retrospective cohort of transplanted hepatocellular carcinoma (HCC) patients, exploring which LI-RADS subclasses need to be considered in order to grant the best Metroticket 2.0 performance. The most recent pre-LT imaging of 245 patients undergoing LT for HCC between 2005 and 2015 was retrospectively and blindly reviewed, classifying all nodules according to LI-RADS protocol. Metroticket 2.0 accuracy was subsequently tested incorporating all vital nodules identified during multi-disciplinary team (MDT) meetings attended before LI-RADS reclassification of the latest pre-LT imaging, LR-5 and LR-treatment-viable (LR-TR-V), LR-4/5 and LR-TR-V, and LR-3/4/5 and LR-TR-V nodules respectively. Considering their extremely low probability for harbouring HCC, LR-1 and LR-2 nodules were not considered in this analysis. Incorporation of all HCCs identified during MDT meetings attended before LI-RADS reclassification of the latest pre-LT imaging resulted in a Metroticket 2.0 c-index of 0.72, [95% confidence interval (CI) 0.64-0.80]. Metroticket 2.0 c-index dropped to 0.60 [95% CI: 0.48-0.72] when LI-RADS-5 and LI-RADS-TR-V (P = 0.0089) or LI-RADS-5, LI-RADS-4 and LI-RADS-TR-V (P = 0.0068) nodules were entered in the calculator. Conversely, addition of LI-RADS-3 HCCs raised the Metroticket 2.0 c-index to 0.65 [95% CI: 0.54-0.86], resulting in a not statistically significant diversion from the original performance (0.72 vs. 0.65; P = 0.08). Exclusion of LR-3 and LR-4 nodules from Metroticket 2.0 calculator resulted in a significant drop in its accuracy. Every nodule with an intermediate-to-high probability of harbouring HCC according to LI-RADS protocol seems to contribute to tumour burden and should be entered in the Metroticket 2.0 calculator in order to grant appropriate performance.

Liver transplantation in malignant disease

Liver transplantation for malignant disease has gained increasing attention as part of transplant oncology. Following the implementation of the Milan criteria, hepatocellular carcinoma (HCC) was the first generally accepted indication for transplantation in patients with cancer. Subsequently, more liberal criteria for HCC have been developed, and research on this topic is still ongoing. The evident success of liver transplantation for HCC has led to the attempt to extend its indication to other malignancies. Regarding perihilar cholangiocarcinoma, more and more evidence supports the use of liver transplantation, especially after neoadjuvant therapy. In addition, some data also show a benefit for selected patients with very early stage intrahepatic cholangiocarcinoma. Hepatic epithelioid hemangioendothelioma is a very rare but nonetheless established indication for liver transplantation in primary liver cancer. In contrast, patients with hepatic angiosarcoma are currently not considered to be optimal candidates. In secondary liver tumors, neuroendocrine cancer liver metastases are an accepted but comparability rare indication for liver transplantation. Recently, some evidence has been published supporting the use of liver transplantation even for colorectal liver metastases. This review summarizes the current evidence for liver transplantation for primary and secondary liver cancer.

Long-term outcomes of deceased donor liver transplantation in hepatocellular carcinoma patients with portal vein tumor thrombus: A multicenter study

BACKGROUND

The incidence of portal vein tumor thrombus (PVTT) has been reported to be as high as approximately 10%-40% in patients with hepatocellular carcinoma (HCC). The long-term prognosis of deceased donor liver transplantation (DDLT) in HCC patients with PVTT remains unknown.

METHODS

Data of 961 HCC patients who underwent DDLT between 2015 and 2018 in six centers were analyzed. Based on the Milan criteria (MC) and Cheng's classification of PVTT, the patients were divided into 4 groups: within MC, beyond MC without PVTT, type 1 PVTT, and type 2 PVTT groups.

RESULTS

489 (50.9%) were within the MC, 296 (30.8%) beyond the MC but without PVTT, 83 (8.6%) type 1 PVTT, and 93 (9.7%) type 2 PVTT. Kaplan-Meier analysis showed that type 1 or 2 PVTT patients with alpha-fetoprotein (AFP) ≤ 100 ng/mL had overall survival (OS) similar to that of patients within the MC (P = 0.957), and superior OS (P = 0.003 and 0.009) and recurrence-free survival (RFS) (P = 0.038 and <0.001) than those of patients beyond the MC and PVTT patients with AFP > 100 ng/mL. Multivariable Cox-regression analysis identified type 1 and 2 PVTT to be independent risk factor for RFS [hazard ratio (HR) 1.523 95% confidence interval (CI) 1.162-1.997, P = 0.002], but not for OS (HR 1.283, 95%CI 0.922-1.786, P = 0.139).

CONCLUSION

HCC patients with type 1 or 2 PVTT may be acceptable candidates for DDLT. To achieve better outcomes, preoperative AFP levels should be seriously considered when selecting patients with PVTT for DDLT.

Inter-center agreement of mRECIST in transplanted patients for hepatocellular carcinoma

OBJECTIVES

To evaluate the inter-observer reliability of modified Response Evaluation Criteria In Solid Tumours (mRECIST) of patients with hepatocellular carcinoma (HCC) undergoing neo-adjuvant treatments before liver transplant (LT). The agreement of tumor number, size, transplant criteria, and the radiological-pathological concordance were also assessed.

METHODS

A total of 180 radiological studies before/after neo-adjuvant therapies performed on 90 patients prior to LT were reviewed from three expert centers. Kappa-statistic and intraclass correlation (ICC) were evaluated on mRECIST and on tumoral features. Complete radiological response (CR) was compared with complete pathological response (CPR).

RESULTS

Before neo-adjuvant therapies, the agreement on tumor number, size, and transplant criteria ranged from moderate (defined as ICC of 0.41-0.60) to almost perfect (ICC of 0.81-0.99), being higher with magnetic resonance imaging (MRI) than CT (0.657-0.899 and 0.422-0.776, respectively). After neo-adjuvant therapies, the agreement decreased, as ICCs ranged between 0.518 and 0.663 with MRI and between 0.508 and 0.677 with CT. Concordant mRECIST pairs were 201 of 270 reviews (76.3%) with a kappa of 0.648 indicating substantial agreement. When the three observers completely agreed on CR, the positive predictive value for CPR was 51.6%. The negative predictive value was 94.2% with a kappa of 0.512 indicating fair agreement between radiology and pathology.

CONCLUSIONS

mRECIST agreement was substantial among the three observers involved. The agreement on tumor number, size, and transplant criteria ranged from moderate to almost perfect, with the highest ICCs obtained with MRI before neo-adjuvant therapies. Finally, the predictive value of mRECIST in the diagnosis of CPR was only fair.

KEY POINTS

• The review of 180 radiological exams of patients with hepatocellular carcinoma before and after neo-adjuvant therapies showed that the concordance among three different raters on mRECIST diagnosis was substantial. • The inter-observer reliability on fulfilment of transplant criteria slightly decreased when evaluated through CT and after loco-regional therapies. • The radiological diagnosis of complete response after neo-adjuvant therapies was predictive of complete pathological response in only 51.6% of cases.

Dynamic α-Fetoprotein Response and Outcomes After Liver Transplant for Hepatocellular Carcinoma

IMPORTANCE

Accurate preoperative prediction of hepatocellular carcinoma (HCC) recurrence after liver transplant is the mainstay of selection tools used by transplant-governing bodies to discern candidacy for patients with HCC. Although progress has been made, few tools incorporate objective measures of tumor biological characteristics, resulting in inclusion of patients with high recurrence rates and exclusion of others who could otherwise be cured.

OBJECTIVE

To externally validate the New York/California (NYCA) score, a recently published multi-institutional US HCC selection tool that was the first model incorporating a dynamic α-fetoprotein response (AFP-R) and compare the validated score with currently accepted HCC selection tools, namely, the Milan Criteria (MC), the French-AFP (F-AFP), and Metroticket 2.0 models.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective, multicenter prognostic analysis of prospectively collected databases of 2236 adults undergoing liver transplant for HCC was conducted at 3 US, 1 Canadian, and 4 European centers from January 1, 2001, to December 31, 2013. The AFP-R was measured as the difference between maximum and final pre-liver transplant AFP level. Cox proportional hazards regression and competing risk regression analyses examined recurrence-free and overall survival. Receiver operating characteristic analyses and net reclassification index were used to compare NYCA with MC, F-AFP, and Metroticket 2.0. Data analysis was performed from June 2019 to April 2020.

MAIN OUTCOMES AND MEASURES

The primary study outcome was 5-year recurrence-free survival; overall survival was the secondary outcome.

RESULTS

Of 2236 patients, 1808 (80.9%) were men; mean (SD) age was 58.3 (7.96) years. A total of 545 patients (24.4%) did not meet the MC. The NYCA score proved valid on competing risk regression analysis, accurately predicting recurrence-free and overall survival (5-year cumulative incidence of recurrence risk in NYCA risk categories was 9.5% for low-, 20.5%, for acceptable-, and 40.5% for high-risk categories; P < .001 for all). The NYCA also predicted recurrence-free survival on a center-specific level: 453 of 545 patients (83.1%) who did not meet MC, 213 of 308 (69.2%) who did not meet the French-AFP, 292 of 384 (76.1%) who did not meet Metroticket 2.0 would be recategorized into NYCA low- and acceptable-risk groups (>75% 5-year recurrence-free survival). The Harrell C statistic for the validated NYCA score was 0.66 compared with 0.59 for the MC and 0.57 for the F-AFP models (P < .001). The net reclassification index for NYCA was 8.1 vs MC, 12.9 vs F-AFP, and 10.1 vs Metroticket 2.0.

CONCLUSIONS AND RELEVANCE

This study appears to externally validate the importance of AFP-R in the selection of patients with HCC for liver transplant. The AFP-R represents one of the truly objective measures of biological characteristics available before transplantation. Incorporation of AFP-R into selection criteria allows safe expansion of MC and other models, offering liver transplant to patients with acceptable tumor biological characteristics who would otherwise be denied potential cure.