Development of models to predict early post-transplant recurrence of hepatocellular carcinoma that also integrate the quality and characteristics of the liver graft: A national registry study in China

Challenges related to clinical decision-making in hepatocellular carcinoma recurrence post-liver transplantation: Is there a hope?

Hepatocellular carcinoma (HCC) is a common liver malignancy and represents a serious cause of cancer-related mortality and morbidity. One of the favourable curative surgical therapeutic options for HCC is liver transplantation (LT) in selected patients fulfilling the known standard Milan/University of California San Francisco criteria which have shown better outcomes and longer-term survival. Despite careful adherence to the strict HCC selection criteria for LT in different transplant centres, the recurrence rate still occurs which could negatively affect HCC patients' survival. Hence HCC recurrence post-LT could predict patients' survival and prognosis, depending on the exact timing of recurrence after LT (early or late), and whether intra/extrahepatic HCC recurrence. Several factors may aid in such a complication, particularly tumour-related criteria including larger sizes, higher grades or poor tumour differentiation, microvascular invasion, and elevated serum alpha-fetoprotein. Therefore, managing such cases is challenging, different therapeutic options have been proposed, including curative surgical and ablative treatments that have shown better outcomes, compared to the palliative locoregional and systemic therapies, which may be helpful in those with unresectable tumour burden. To handle all these issues in our review.

Liver Transplantation for Hepatocarcinoma: Results over Two Decades of a Transplantation Programme and Analysis of Factors Associated with Recurrence

BACKGROUND

In recent years, many studies have attempted to develop models to predict the recurrence of hepatocarcinoma after liver transplantation.

METHOD

A single-centre, retrospective cohort study analysed patients receiving transplants due to hepatocarcinoma during the 20 years of the transplant programme. We analysed patient survival, hepatocarcinoma recurrence and the influence of the different factors described in the literature as related to hepatocarcinoma recurrence. We compared the results of previous items between the first and second decades of the transplantation programme (1995-2010 and 2010-2020).

RESULTS

Of 265 patients, the patient survival rate was 68% at 5 years, 58% at 10 years, 45% at 15 years and 34% at 20 years. The overall recurrence rate of hepatocarcinoma was 14.5%, without differences between periods. Of these, 54% of recurrences occurred early, in the first two years after transplantation. Of the parameters analysed, an alpha-fetoprotein level of >16 ng/mL, the type of immunosuppression used and the characteristics of the pathological anatomy of the explant were significant. A trend towards statistical significance was identified for the number of nodules and the size of the largest nodule. Logistic regression analysis was used to develop a model with a sensitivity of 85.7% and a specificity of 35.7% to predict recurrences in our cohort. Regarding the comparison between periods, the survival and recurrence rates of hepatocarcinoma were similar. The impact of the factors analysed in both decades was similar.

CONCLUSIONS

Most recurrences occur during the first two years post-transplantation, so closer follow-ups should be performed during this period, especially in those patients where the model predicts a high risk of recurrence. The detection of patients at higher risk of recurrence allows for closer follow-up and may, in the future, make them candidates for adjuvant or neoadjuvant systemic therapies to transplantation.

Effect of intermittent Pringle maneuver on perioperative outcomes and long-term survival following liver resection in patients with hepatocellular carcinoma: a meta-analysis and systemic review

BACKGROUND

Intermittent Pringle maneuver (IPM) is commonly used to control bleeding during liver resection. IPM can cause ischemia-reperfusion injury, which may affect the prognosis of patients with hepatocellular carcinoma (HCC). The present meta-analysis was conducted to evaluate the effect of IPM use on perioperative outcomes and long-term survival in patients with HCC.

METHODS

A systemic literature search was performed in the PubMed, Embase, Web of Science, and Cochrane Library databases to identify randomized controlled trials and retrospective studies that compared the effect of IPM with no Pringle maneuver during liver resection in patients with HCC. Hazard ratio (HR), risk ratio, standardized mean difference, and their 95% confidence interval (CI) values were calculated based on the type of variables.

RESULTS

This meta-analysis included nine studies comprising one RCT and eight retrospective studies and involved a total of 3268 patients. Perioperative outcomes, including operation time, complications, and length of hospital stay, except for blood loss, were comparable between the two groups. After removing the studies that led to heterogeneity, the results showed that IPM was effective in reducing blood loss. Five studies reported overall survival (OS) and disease-free survival (DFS) data and eight studies reported perioperative outcomes. No significant difference in OS and DFS was observed between the two groups (OS: HR, 1.01; 95% CI, 0.85-1.20; p = 0.95; DFS: HR, 1.01; 95% CI, 0.88-1.17; p = 0.86).

CONCLUSION

IPM is a useful technique to control blood loss during liver resection and does not affect the long-term survival of patients with HCC.

Molecular Clues for Prediction of Hepatocellular Carcinoma Recurrence After Liver Transplantation

Recurrence after liver transplantation (LT) for hepatocellular carcinoma (HCC) is one of the commonest causes of cancer-related mortality. Thus, advances in the HCC molecular features have paid researchers great attention to identifying the different risk factors that could aid in liver cancer initiation and progression for earlier prediction of post-operative HCC recurrence risk. Our review has focused on the possible molecular onco-drivers' for HCC recurrence post-LT that may represent diagnostic/prognostic tools and scoring models for the proper selection of LT candidates with HCC.

Multiple Pretransplant Treatments for Patients Without Pathological Complete Response may Worsen Posttransplant Outcomes in Patients with Hepatocellular Carcinoma

BACKGROUND

Liver transplant (LT) candidates with hepatocellular carcinoma (HCC) often receive cancer treatment before transplant. We investigated the impact of pre-transplant treatment for HCC on the risk of posttransplant recurrence.

METHODS

Adult HCC patients with LT at our institution between 2013 and 2020 were included. The impact of pre-LT cancer treatments on the cumulative recurrence was evaluated, using the Gray and Fine-Gray methods adjusted for confounding factors. Outcomes were considered in two ways: 1) by pathologically complete response (pCR) status within patients received pre-LT treatment; and 2) within patients without pCR, grouped by pre-LT treatment as A) none; B) one treatment; C) multiple treatments.

RESULTS

The sample included 179 patients, of whom 151 (84%) received pretreatment and 42 (28% of treated) demonstrated pCR. Overall, 22 (12%) patients experienced recurrence. The 5-year cumulative post-LT recurrence rate was significantly lower in patients with pCR than those without pCR (4.8% vs. 19.2%, P = 0.03). In bivariable analyses, pCR significantly decreased risk of recurrence. Among the 137 patients without pCR (viable HCC in the explant), 28 (20%) had no pretreatment (A), 70 (52%) had one treatment (B), and 39 (20%) had multiple treatments (C). Patients in Group C had higher 5-year recurrence rates than those in A or B (39.6% vs. 8.2%, 6.5%, P = 0.004 and P < 0.001, respectively). In bivariable analyses, multiple treatments was significantly associated with recurrence.

CONCLUSIONS

pCR is a favorable prognostic factor after LT. When pCR was not achieved by pre-LT treatment, the number of treatments might be associated with post-LT oncological prognosis.

One Shoot, Two Birds: Alleviating Inflammation Caused by Ischemia/Reperfusion Injury to Reduce the Recurrence of Hepatocellular Carcinoma

Inflammation is crucial to tumorigenesis and the development of metastasis. Hepatic ischemia/reperfusion injury (IRI) is an unresolved problem in liver resection and transplantation which often establishes and remodels the inflammatory microenvironment in liver. More and more experimental and clinical evidence unmasks the role of hepatic IRI and associated inflammation in promoting the recurrence of hepatocellular carcinoma (HCC). Meanwhile, approaches aimed at alleviating hepatic IRI, such as machine perfusion, regulating the gut-liver axis, and targeting key inflammatory components, have been proved to prevent HCC recurrence. This review article highlights the underlying mechanisms and promising therapeutic strategies to reduce tumor recurrence through alleviating inflammation induced by hepatic IRI.

Deep learning for prediction of hepatocellular carcinoma recurrence after resection or liver transplantation: a discovery and validation study

BACKGROUND

There is a growing need for new improved classifiers of prognosis in hepatocellular carcinoma (HCC) patients to stratify them effectively.

METHODS

A deep learning model was developed on a total of 1118 patients from 4 independent cohorts. A nucleus map set (n = 120) was used to train U-net to capture the nuclear architecture. The training set (n = 552) included HCC patients that had been treated by resection. The liver transplantation (LT) set (n = 144) contained patients with HCC that had been treated by LT. The train set and its nuclear architectural information extracted by U-net were used to train the MobileNet V2-based classifier (MobileNetV2_HCC_class). The classifier was then independently tested on the LT set and externally validated on the TCGA set (n = 302). The primary outcome was recurrence free survival (RFS).

RESULTS

The MobileNetV2_HCC_class was a strong predictor of RFS in both LT set and TCGA set. The classifier provided a hazard ratio of 3.44 (95% CI 2.01-5.87, p < 0.001) for high risk versus low risk in the LT set, and 2.55 (95% CI 1.64-3.99, p < 0.001) when known prognostic factors, remarkable in univariable analyses on the same cohort, were adjusted. The MobileNetV2_HCC_class maintained a relatively higher discriminatory power [time-dependent accuracy and area under curve (AUC)] than other factors after LT or resection in the independent validation set (LT and TCGA set). Net reclassification improvement (NRI) analysis indicated MobileNetV2_HCC_class exhibited better net benefits for the Stage_AJCC beyond other independent factors. A pathological review demonstrated that tumoral areas with the highest recurrence predictability featured the following features: the presence of stroma, a high degree of cytological atypia, nuclear hyperchromasia, and a lack of immune cell infiltration.

CONCLUSION

A prognostic classifier for clinical purposes had been proposed based on the use of deep learning on histological slides from HCC patients. This classifier assists in refining the prognostic prediction of HCC patients and identifies patients who have been benefited from more intensive management.

Ischemic-Free Liver Transplantation Reduces the Recurrence of Hepatocellular Carcinoma After Liver Transplantation

Ischemia reperfusion injury (IRI) is an adverse factor for hepatocellular carcinoma (HCC) recurrence after liver transplantation. Ischemic-free liver transplantation (IFLT) is a novel transplant procedure that can largely reduce or even prevent IRI, but the clinical relevance of IFLT and the recurrence of HCC after liver transplantation are still unknown. This retrospective study compared survival outcomes, HCC recurrence, perioperative data and IRI severity following liver transplantation (LT). 30 patients received IFLT and 196 patients received conventional liver transplantation (CLT) were chosen for the entire cohort between June 2017 and August 2020. A 1:3 propensity score matching was performed, 30 IFLT recipients and 85 matched CLT patients were enrolled in propensity-matched cohorts. An univariate and multivariate Cox regression analysis was performed, and showed surgical procedure (CLT vs IFLT) was an independent prognostic factor (HR 3.728, 95% CI 1.172-11.861, P=0.026) for recurrence free survival (RFS) in HCC patients following liver transplantation. In the Kaplan–Meier analysis, the RFS rates at 1 and 3 years after LT in recipients with HCC in the IFLT group were significantly higher than those in the CLT group both in the entire cohort and propensity-matched cohort (P=0.006 and P=0.048, respectively). In addition, patients in the IFLT group had a lower serum lactate level, lower serum ALT level and serum AST level on postoperative Day 1. LT recipients with HCC in the IFLT group had a lower incidence of early allograft dysfunction than LT recipients with HCC in the CLT group. Histological analysis showed no obvious hepatocyte necrosis or apoptosis in IFLT group. In conclusion, IFLT can significantly reduce IRI damage and has the potential to be a useful strategy to reduce HCC recurrence after liver transplantation.

Influence of the ABO Blood Group System on Hepatocellular Carcinoma Recurrence After Liver Transplantation

BACKGROUND

The ABO blood group system may influence tumorigenesis, but its prognostic value in liver transplantation (LT) for hepatocellular carcinoma (HCC) has never been assessed.

METHODS

All consecutive patients who underwent LT for HCC between 2013 and 2017 at 9 centers were analyzed. Predictors of tumor recurrence were identified using multivariable analysis, while comparison between group A and non-A recipients was performed after propensity score matching.

RESULTS

Among 925 LT recipients, 406 were blood group A, 94 group B, 380 group O, and 45 group AB. On multivariable analysis, group A was associated with tumor recurrence (hazard ratio [HR] = 1.574 [95% confidence interval; 95% CI = 1.034-2.394] P = 0.034). After propensity score matching, 1- and 5-y recurrence rates were 7.4% and 20.1% in group A recipients versus 3.3% and 13.2% in non-A recipients (HR = 1.66 [95% CI = 1.12-2.45], P = 0.011). One and 5-y recurrence-free survivals were 85.2% and 66.8% in group A recipients versus 88.5% and 71.3% in non-A recipients (HR = 1.38 [95% CI = 1.01-1.90], P = 0.045). Among recipients within Milan criteria (n = 604), 1- and 5-y recurrence rates were 5.8% and 12.7% in group A recipients versus 3.1% and 12.2% in non-A recipients (HR = 1.197 [95% CI = 0.721-1.987], P = 0.485). Among recipients outside Milan criteria (n = 182), 1- and 5-y recurrence rates were 12.1% and 43.8% in group A recipients versus 3.9% and 15.6% in non-A recipients (HR = 3.175 [95% CI = 1.526-6.608], P = 0.002).

CONCLUSIONS

ABO blood system influences the oncological outcome of recipients undergoing LT for HCC. Its incorporation in the prognostication model of LT for HCC may allow improving the management of LT candidates.

Transcatheter arterial chemoembolization combined with Hippo/YAP inhibition significantly improve the survival of rats with transplanted hepatocellular carcinoma

Background

This study aimed to explore the effect of inhibiting the Hippo/Yes-associated protein (YAP) signaling pathway on the outcomes of transcatheter arterial chemoembolization (TACE) in treating transplanted hepatocellular carcinoma (HCC).

Methods

A transplanted HCC rat model was established. Then, rats were randomly divided into four groups: Sham, TACE, verteporfin (inhibitor of Hippo/YAP), and TACE+verteporfin. Lent-OE-YAP was transfected into rats to overexpress YAP in vivo. After treatments, morphological changes, tumor weight, and the overall survival of rats in different groups were analyzed. Real-time PCR, immunohistochemistry staining, and Western blotting were used to determine the expression of factors related to the Hippo/YAP signaling pathway.

Results

Tumor weight and tissue lesions in the TACE and verteporfin groups were significantly reduced compared with the Sham group. Verteporfin significantly decreased tumor weight after TACE treatment. In addition, verteporfin significantly improved the overall survival of rats with transplanted HCC after TACE treatment. Compared with the Sham group, both TACE and verteporfin groups exhibited significantly decreased expression of macrophage-stimulating (MST)1, MST2, long-acting thyroid stimulator 1, transcriptional co-activator with PDZ-binding motif (TAZ), Yes-associated protein (YAP), TEA domain transcription factor (TEAD)1, TEAD2, TEAD3, and TEAD4. TACE plus verteporfin significantly enhanced the downregulation of effectors in the Hippo/YAP signaling pathway and decreased tumor size, while the overexpression of YAP exerted opposite effects.

Conclusion

The inhibition of the Hippo/YAP signaling pathway via verteporfin significantly improved the outcomes of TACE in treating transplanted HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01486-w.

Systematic review: risk prediction models for recurrence of hepatocellular carcinoma after liver transplantation

Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) is a significant clinical problem associated with poor surgical outcomes. This study aims to summarize the current evidence on risk prediction models of HCC recurrence after LT. PubMed and EMBASE were searched to May 25, 2019, for relevant articles. Studies originally designed to develop or validate a risk prediction model for HCC recurrence after LT were included. Two independent authors summarized the study characteristics and evaluated the risk of bias and applicability concerns in the included studies. From 26 included studies, 18 original risk prediction models were determined, but only five models were externally validated. The average number of predictors involved in the construction of risk models was three. The most frequently employed predictors were alpha-fetoprotein, tumor size, vascular invasion, tumor number, tumor differentiation, and neutrophil-lymphocyte ratio. Most studies showed good discriminatory performance (AUC >0.75). The overall quality of the included studies was generally low. Most of the original models lacked the highly recommended external and prospective validation in diverse populations. The AFP model was the well-validated preoperative risk model that can stratify patients into high- and low-risk groups.