From a Philosophical Framework to a Valid Prognostic Staging System of the New "Comprehensive Assessment" for Transplantable Hepatocellular Carcinoma

Surgical Treatment of Hepatocellular Carcinoma: Multicenter Competing-risk Analysis of Tumor-related Death Following Liver Resection and Transplantation Under an Intention-to-treat Perspective

BACKGROUND

Early-stage hepatocellular carcinoma could benefit from upfront liver resection (LR) or liver transplantation (LT), but the optimal strategy in terms of tumor-related outcomes is still debated. We compared the oncological outcomes of LR and LT for hepatocellular carcinoma, stratifying the study population into a low-, intermediate-, and high-risk class according to the risk of death at 5-y predicted by a previously developed prognostic model. The impact of tumor pathology on oncological outcomes of low- and intermediate-risk patients undergoing LR was investigated as a secondary outcome.

METHODS

We performed a retrospective multicentric cohort study involving 2640 patients consecutively treated by LR or LT from 4 tertiary hepatobiliary and transplant centers between 2005 and 2015, focusing on patients amenable to both treatments upfront. Tumor-related survival and overall survival were compared under an intention-to-treat perspective.

RESULTS

We identified 468 LR and 579 LT candidates: 512 LT candidates underwent LT, whereas 68 (11.7%) dropped-out for tumor progression. Ninety-nine high-risk patients were selected from each treatment cohort after propensity score matching. Three and 5-y cumulative incidence of tumor-related death were 29.7% and 39.5% versus 17.2% and 18.3% for LR and LT group ( P = 0.039), respectively. Low-risk and intermediate-risk patients treated by LR and presenting satellite nodules and microvascular invasion had a significantly higher 5-y incidence of tumor-related death (29.2% versus 12.5%; P < 0.001).

CONCLUSIONS

High-risk patients showed significantly better intention-to-treat tumor-related survival after upfront LT rather than LR. Cancer-specific survival of low- and intermediate-risk LR patients was significantly impaired by unfavorable pathology, suggesting the application of ab-initio salvage LT in such scenarios.

How important is the role of iterative liver direct surgery in patients with hepatocellular carcinoma for a transplant center located in an area with a low rate of deceased donation?

Introduction

Hepatocellular carcinoma (HCC) accounts for nearly 90% of primary liver cancers, with estimates of over 1 million people affected by 2025. We aimed to explore the impacting role of an iterative surgical treatment approach in a cohort of HCC patients within the Milan criteria, associated with clinical risk factors for tumor recurrence (RHCC) after liver transplant (LT) and loco-regional therapies (LRT), as well as liver resection (LR) and/or microwave thermal ablation (MWTA).

Methods

We retrospectively analyzed our experience performed during an 8-year period between January 2013 and December 2021 in patients treated for HCC, focusing on describing the impact on preoperative end-stage liver disease severity, oncologic staging, tumor characteristics, and surgical treatments. The Cox model was used to evaluate variables that could predict relapse risks. Relapse risk curves were calculated according to the Kaplan–Meier method, and the log-rank test was used to compare them.

Results

There were 557 HCC patients treated with a first-line approach of LR and/or LRTs (n = 335) or LT (n = 222). The median age at initial transplantation was 59 versus 68 for those whose first surgical approach was LR and/or LRT. In univariate analysis with the Cox model, nodule size was the single predictor of recurrence of HCC in the posttreatment setting (HR: 1.61, 95% CI: 1.05–2.47, p = 0.030). For the LRT group, we have enlightened the following clinical characteristics as significantly associated with RHCC: hepatitis B virus infection (which has a protective role with HR: 0.34, 95% CI: 0.13–0.94, p = 0.038), number of HCC nodules (HR: 1.54, 95% CI: 1.22–1.94, p &lt; 0.001), size of the largest nodule (HR: 1.06, 95% CI: 1.01–1.12, p = 0.023), serum bilirubin (HR: 1.57, 95% CI: 1.03–2.40, p = 0.038), and international normalized ratio (HR: 16.40, 95% CI: 2.30–118.0, p = 0.006). Among the overall 111 patients with RHCC in the LRT group, 33 were iteratively treated with further curative treatment (12 were treated with LR, two with MWTA, three with a combined LR-MWTA treatment, and 16 underwent LT). Only one of 18 recurrent patients previously treated with LT underwent LR. For these RHCC patients, multivariable analysis showed the protective roles of LT for primary RHCC after IDLS (HR: 0.06, 95% CI: 0.01–0.36, p = 0.002), of the time relapsed between the first and second IDLS treatments (HR: 0.97, 95% CI: 0.94–0.99, p = 0.044), and the impact of previous minimally invasive treatment (HR: 0.28, 95% CI: 0.08–1.00, p = 0.051).

Conclusion

The coexistence of RHCC with underlying cirrhosis increases the complexity of assessing the net health benefit of ILDS before LT. Minimally invasive surgical therapies and time to HCC relapse should be considered an outcome in randomized clinical trials because they have a relevant impact on tumor-free survival.

Role of Pretransplant Treatments for Patients with Hepatocellular Carcinoma Waiting for Liver Transplantation

Simple Summary

Hepatocellular carcinoma (HCC) is the fifth most common cancer in men worldwide and the second leading cause of cancer death. Liver transplantation (LT) is one of the treatment options for patients with HCC. Recently, there have been many reports of the usefulness of locoregional therapy, such as transarterial chemoembolization and radiofrequency ablation, for HCC as pretreatment before LT. In Western countries, locoregional therapy is used to bridge until transplantation to prevent drop-outs from the waiting list or for downstaging to treat patients with advanced HCC who initially exceed the criteria for LT. With the progress of locoregional therapy, new reports on the effects of bridging and downstaging locoregional therapy as pretransplant treatment are increasing in number.

Abstract

Recently, there have been many reports of the usefulness of locoregional therapy such as transarterial chemoembolization and radiofrequency ablation for hepatocellular carcinoma (HCC) as pretreatment before liver transplantation (LT). Locoregional therapy is performed with curative intent in Japan, where living donor LT constitutes the majority of LT due to the critical shortage of deceased donors. However, in Western countries, where deceased donor LT is the main procedure, LT is indicated for early-stage HCC regardless of liver functional reserve, and locoregional therapy is used for bridging until transplantation to prevent drop-outs from the waiting list or for downstaging to treat patients with advanced HCC who initially exceed the criteria for LT. There are many reports of the effect of bridging and downstaging locoregional therapy before LT, and its indications and efficacy are becoming clear. Responses to locoregional therapy, such as changes in tumor markers, the avidity of FDG-PET, etc., are considered useful for successful bridging and downstaging. In this review, the effects of bridging and downstaging locoregional therapy as a pretransplant treatment on the results of transplantation are clarified, focusing on recent reports.

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.

Upper Limits of Downstaging for Hepatocellular Carcinoma in Liver Transplantation

In Europe and the United States, approximately 1100 and 1800 liver transplantations, respectively, are performed every year for hepatocellular carcinoma (HCC), compared with an annual incidence of 65,000 and 39,000 new cases, respectively. Because of organ shortages, proper patient selection is crucial, especially for those exceeding the Milan criteria. Downstaging is the reduction of the HCC burden to meet the eligibility criteria for liver transplantation. Many techniques can be used in downstaging, including ablation, chemoembolisation, radioembolisation and systemic treatments, with a reported success rate of 60-70%. In recent years, an increasing number of patient responders to downstaging procedures has been included in the waitlist, generally with a comparable five-year post-transplant survival but with a higher probability of dropout than HCC patients within the Milan criteria. While the Milan criteria are generally accepted as the endpoint of downstaging, the upper limits of tumour burden for downstaging HCC for liver transplantation are controversial. Very challenging situations involve HCC patients with large nodules, macrovascular invasion or even extrahepatic metastasis at baseline who respond to increasingly more effective downstaging procedures and who aspire to be placed on the waitlist for transplantation. This narrative review analyses the most important evidence available on cohorts subjected to "extended" downstaging, including HCC patients over the up-to-seven criteria and over the University of California San Francisco downstaging criteria. We also address surrogate markers of biological aggressiveness, such as alpha-fetoprotein and the response stability to locoregional treatments, which are very useful in selecting responders to downstaging procedures for waitlisting inclusion.

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.

Locoregional Treatments for Bridging and Downstaging HCC to Liver Transplantation

Liver transplantation (LT) is the first-line treatment for patients diagnosed with unresectable early-stage hepatocellular carcinoma (HCC) in the setting of cirrhosis. It is well known that HCC patients within the Milan criteria (solitary tumour ≤ 5 cm or ≤3 tumours, each <3 cm) could undergo LT with excellent results. However, there is a growing tendency to enlarge inclusion criteria since the Milan criteria are nowadays considered too restrictive and may exclude patients who would benefit from LT. On the other hand, there is a persistent shortage of donor organs. In this scenario, there is consensus about the role of loco-regional therapy (LRT) during the waiting list to select patients who would benefit more from LT, reducing the risk of drop off from the waiting list as well as decreasing tumour dimension to meet acceptable criteria for LT. In this review, current evidence on the safety, efficacy and utility of LRTs as neoadjuvant therapies before LT are summarized.

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.

The Treatment Effect of Liver Transplantation versus Liver Resection for HCC: A Review and Future Perspectives

For patients presenting with hepatocellular carcinoma within the Milan criteria, either liver resection or liver transplantation can be performed. However, to what extent either of these treatment options is superior in terms of long-term survival is unknown. Obviously, the comparison of these treatments is complicated by several selection processes. In this article, we comprehensively review the current literature with a focus on factors accounting for selection bias. Thus far, studies that did not perform an intention-to-treat analysis conclude that liver transplantation is superior to liver resection for early-stage hepatocellular carcinoma. In contrast, studies performing an intention-to-treat analysis state that survival is comparable between both modalities. Furthermore, all studies demonstrate that disease-free survival is longer after liver transplantation compared to liver resection. With respect to the latter, implications of recurrences for survival are rarely discussed. Heterogeneous treatment effects and logical inconsistencies indicate that studies with a higher level of evidence are needed to determine if liver transplantation offers a survival benefit over liver resection. However, randomised controlled trials, as the golden standard, are believed to be infeasible. Therefore, we suggest an alternative research design from the causal inference literature. The rationale for a regression discontinuity design that exploits the natural experiment created by the widely adopted Milan criteria will be discussed. In this type of study, the analysis is focused on liver transplantation patients just within the Milan criteria and liver resection patients just outside, hereby ensuring equal distribution of confounders.

Characteristics and Survival Outcomes of Hepatocellular Carcinoma Developed after HCV SVR

The clinical presentation and survival of hepatocellular carcinoma (HCC) after hepatitis C virus (HCV) eradication as compared to HCC in viremic patients are not well characterized. We aimed to investigate the characteristics and survival between HCV patients with and without viremia at HCC diagnosis.: We retrospectively analyzed overall survival outcomes in 1389 HCV-related HCC patients, including 301 with HCC developed after HCV eradication (post-SVR HCC) and 1088 with HCV viremia at HCC diagnosis (viremic HCC). We also evaluated overall survival in the two groups using propensity score-matching methods.: At HCC diagnosis, post-SVR HCC patients were older, less obese, less likely cirrhotic, with better liver function, lower alfa-fetoprotein levels, earlier BCLC stages, and higher rate of treatment with surgery. Overall, post-SVR HCC patients had higher median survival than viremic patients (153.3 vs. 55.6 months, p < 0.01), but post-SVR HCC was not independently associated with survival on multivariate analysis (adjusted HR: 1.05, 95% CI: 0.76-1.47). However, on sub-analysis, viremic HCC patients who subsequently received anti-viral treatment and achieved SVR had higher median survival than post-SVR HCC patients (p < 0.01). Viremic HCC with subsequent SVR was also significantly associated with lower mortality as compared to post-SVR HCC (adjusted HR: 0.18, 95% CI: 0.11-0.29). In addition, we observed similar findings in our analysis of the propensity score-matched cohorts.: The advantages in clinical and tumor characters at HCC diagnosis determined the better overall survival of post-SVR HCC patients; however, HCV eradication after HCC development was also associated with improved survival.

The Endless Sources of Hepatocellular Carcinoma Heterogeneity

Hepatocellular carcinoma (HCC) represents a global health problem. The incidence keeps increasing and current therapeutic options confer limited benefits to the patients. Tumor heterogeneity plays a central role in this context, limiting the availability of predictive biomarkers and complicating the criteria used to choose the most suitable therapeutic option. HCC heterogeneity occurs at different levels: within the population (inter-patient heterogeneity) and within tumors from the same patient (intra-patient and intra-tumor heterogeneity). Experts in the field have made many efforts to classify the patients based on clinicopathological characteristics and molecular signatures; however, there is still much work ahead to be able to integrate the extra-tumor heterogeneity that emerges from the complexity of the tumor microenvironment, which plays a critical role in the pathogenesis of the disease and therapy responses. In this review, we summarize tumor intrinsic and extrinsic sources of heterogeneity of the most common etiologies of HCC and summarize the most recent discoveries regarding the evolutionary trajectory of liver cancer cells and the influence of tumor-extrinsic factors such as the microbiome and the host immune system. We further highlight the potential of novel high-throughput methodologies to contribute to a better understanding of this devastating disease and to the improvement of the clinical management of patients.

Liver Transplantation for Hepatocellular Carcinoma: A Real-Life Comparison of Milan Criteria and AFP Model

Simple Summary

The α-fetoprotein (AFP) model officially replaced the Milan criteria in France for liver transplantation (LT) for hepatocellular carcinoma (HCC) in January 2013. The aim of our retrospective study was to analyze the agreement of the criteria and the results of LT with an intention-to-treat design since the adoption of the AFP model and to compare them to the practice and results of LT before the adoption of the AFP model. We did not observe significant changes in practices in 523 consecutively listed patients, with a good agreement (88%) to AFP criteria on the explants before and after the adoption of the AFP model. However, the prognosis of patients listed in the most recent period was worse, maybe because of a significant increase in bridging treatments and in the waiting time. This observational study provides an insight into the real-life course of LT for HCC.

Abstract

Purpose: To compare the agreement for the criteria on the explant and the results of liver transplantation (LT) before and after adoption of the AFP (α-fetoprotein) model. Methods: 523 patients consecutively listed in five French centers were reviewed to compare results of the Milan criteria period (MilanCP, n = 199) (before 2013) and the AFP score period (AFPscP, n = 324) (after 2013). (NCT03156582). Results: During AFPscP, there was a significantly longer waiting time on the list (12.3 vs. 7.7 months, p < 0.001) and higher rate of bridging therapies (84 vs. 75%, p = 0.012) compared to the MilanCP. Dropout rate was slightly higher in the AFPscP (31 vs. 24%, p = 0.073). No difference was found in the histological AFP score between groups (p = 0.838) with a global agreement in 88% of patients. Post-LT recurrence was 9.2% in MilanCP vs. 13.2% in AFPscP (p = 0.239) and predictive factors were AFP > 2 on the last imaging, downstaging policy and salvage transplantation. Post-LT survival was similar (83 vs. 87% after 2 years, p = 0.100), but after propensity score analysis, the post-listing overall survival (OS) was worse in the AFPscP (HR 1.45, p = 0.045). Conclusions: Agreement for the AFP model on explant analysis (≤2) did not significantly change. AFP score > 2 was the major prognostic factor for recurrence. Graft allocation policy has a major impact on prognosis, with a post-listing OS significantly decreased, probably due to the increase in waiting time, increase in bridging therapies, downstaging policy and salvage transplantation.

The Impact of Time Interval between Hepatic Resection and Liver Transplantation on Clinical Outcome in Patients with Hepatocellular Carcinoma

Simple Summary

Recurrence of disease or worsening of liver function after hepatic resection (HR) for hepatocellular carcinoma (HCC) may require secondary liver transplantation (SLT). However, a history of HR is supposed to increase the surgical complexity of LT. This is one of the largest series of SLT and it demonstrates that among all the features analyzed regarding the prior HR, only time interval between HR and SLT was an independent predictor of severe complications after SLT. In particular, an increasing probability of severe complications was observed in those patients who were transplanted close (<15 months) to the HR. There was no significant association between HCC-related death and the time between HR and SLT at the multivariable competing risks regression model. Furthermore, these results remained inside the benchmark values recently reported for LT, confirming that tertiary referral centers with consistent experience in HPB surgery and LT may have benefits in both fields.

Abstract

Hepatic resection (HR) for hepatocellular carcinoma (HCC) may require secondary liver transplantation (SLT). However, a previous HR is supposed to worsen post-SLT outcomes. Data of patients treated by SLT between 2000 and 2018 at two tertiary referral centers were analyzed. The primary outcome of the study was to analyze the impact of HR on post-LT complications. A Comprehensive Complication Index ≥ 29.6 was chosen as cutoff. The secondary outcome was HCC-related death by means of competing-risk regression analysis. In the study period, 140 patients were included. Patients were transplanted in a median of 23 months after HR (IQR 14–41). Among all the features analyzed regarding the prior HR, only time interval between HR and SLT (time HR-SLT) was an independent predictor of severe complications after LT (OR = 0.98, p < 0.001). According to fractional polynomial regression, the probability of severe complications increased up to 15 months after HR (43%), then slowly decreased over time (OR = 0.88, p < 0.001). There was no significant association between HCC-related death and time HR-SLT at the multivariable competing risks regression model (SHR, 1.06; 95% CI: 0.69–1.62, p = 0.796). This study showed that time HR-SLT was key in predicting complications after LT, without affecting HCC-related death.

Surgical Resection vs. Percutaneous Ablation for Single Hepatocellular Carcinoma: Exploring the Impact of Li-RADS Classification on Oncological Outcomes

Background: Single hepatocellular carcinoma (HCC) benefits from surgical resection (SR) or US-guided percutaneous ablation (PA), although the best approach is still debated. We evaluated the impact of Li-RADS classification on the oncological outcomes of SR vs. PA as single HCC first-line treatment. Methods: We retrospectively and blindly classified treatment-naïve single HCC that underwent SR or PA between 2010 and 2016 according to Li-RADS protocol. Overall survival (OS), recurrence free survival (RFS) and local recurrence after SR and PA were compared for each Li-RADS subclass before and after propensity-score matching (PS-M). Results: Considering the general population, SR showed better 5-year OS (68.3% vs. 52.2%; p = 0.049) and RFS (42.5% vs. 29.8%; p = 0.002), with lower incidence of local recurrence (8.2% vs. 44.4%; p < 0.001), despite a significantly higher frequency of clinically-relevant complications (12.8% vs. 1.9%; p = 0.002) and a higher Comprehensive Complication Index (12.1 vs. 2.2; p < 0.001). Focusing on different Li-RADS subclasses, we highlighted better 5-year OS (67.1% vs. 46.2%; p = 0.035), RFS (45.0% vs. 27.0% RFS; p < 0.001) and lower incidence of local recurrence (9.7% vs. 48.6%; p < 0.001) after SR for Li-RADS-5 HCCs, while these outcomes did not differ for Li-RADS-3/4 subclasses; such results were confirmed after PS-M. Conclusions: Our analysis suggests a potential prognostic role of Li-RADS classification, supporting SR over PA especially for Li-RADS-5 single HCC.

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

BACKGROUND & AIMS

In the context of liver transplantation (LT) for hepatocellular carcinoma (HCC), prediction models are used to ensure that the risk of post-LT recurrence is acceptably low. However, the weighting that 'response to neoadjuvant therapies' should have in such models remains unclear. Herein, we aimed to incorporate radiological response into the Metroticket 2.0 model for post-LT prediction of "HCC-related death", to improve its clinical utility.

METHODS

Data from 859 transplanted patients (2000-2015) who received neoadjuvant therapies were included. The last radiological assessment before LT was reviewed according to the modified RECIST criteria. Competing-risk analysis was applied. The added value of including radiological response into the Metroticket 2.0 was explored through category-based net reclassification improvement (NRI) analysis.

RESULTS

At last radiological assessment prior to LT, complete response (CR) was diagnosed in 41.3%, partial response/stable disease (PR/SD) in 24.9% and progressive disease (PD) in 33.8% of patients. The 5-year rates of "HCC-related death" were 3.1%, 9.6% and 13.4% in those with CR, PR/SD, or PD, respectively (p <0.001). Log₁₀AFP (p <0.001) and the sum of number and diameter of the tumour/s (p <0.05) were determinants of "HCC-related death" for PR/SD and PD patients. To maintain the post-LT 5-year incidence of "HCC-related death" <30%, the Metroticket 2.0 criteria were restricted in some cases of PR/SD and in all cases with PD, correctly reclassifying 9.4% of patients with "HCC-related death", at the expense of 3.5% of patients who did not have the event. The overall/net NRI was 5.8.

CONCLUSION

Incorporating the modified RECIST criteria into the Metroticket 2.0 framework can improve its predictive ability. The additional information provided can be used to better judge the suitability of candidates for LT following neoadjuvant therapies.

LAY SUMMARY

In the context of liver transplantation for patients with hepatocellular carcinoma, prediction models are used to ensure that the risk of recurrence after transplantation is acceptably low. The Metroticket 2.0 model has been proposed as an accurate predictor of "tumour-related death" after liver transplantation. In the present study, we show that its accuracy can be improved by incorporating information relating to the radiological responses of patients to neoadjuvant therapies.