Hepatic ischemia-reperfusion injury (IRI) represents a major challenge during liver surgery, liver preservation for transplantation, and can cause hemorrhagic shock with severe hypoxemia and trauma. The reduction of blood supply with a concomitant deficit in oxygen delivery initiates various molecular mechanisms involving the innate and adaptive immune response, alterations in gene transcription, induction of cell death programs, and changes in metabolic state and vascular function. Hepatic IRI is a major cause of morbidity and mortality, and is associated with an increased risk for tumor growth and recurrence after oncologic surgery for primary and secondary hepatobiliary malignancies. Therapeutic strategies to prevent or treat hepatic IRI have been investigated in animal models but, for the most part, have failed to provide a protective effect in a clinical setting. This review focuses on the molecular mechanisms underlying hepatic IRI and regeneration, as well as its clinical implications. A better understanding of this complex and highly dynamic process may allow for the development of innovative therapeutic approaches and optimize patient outcomes.

Early conversion to a calcineurin-inhibitor (CNI)-free maintenance immunosuppression with sirolimus (SRL), mycophenolate mofetil (MMF) and steroids was associated with an improved 1-year renal function as compared with a cyclosporine (CsA)-based regimen (SMART core-study). This observational follow-up describes 132 patients followed up within the SMART study framework for 36 months. At 36 months, renal function continued to be superior in SRL-treated patients [ITT-eGFR_@36m: 60.88 vs. 53.72 (CsA) ml/min/1.73 m², P = 0.031]. However, significantly more patients discontinued therapy in the SRL group 59.4% vs.42.3% (CsA). Patient [99% (SRL) vs.97% (CsA) and graft 96% (SRL) vs.94% (CsA)] survival at 36 months was excellent in both arms. There was no difference in late rejection episodes. Late infections and adverse events were similar in both arms except of a higher rate of hyperlipidemia in SRL and a higher incidence of malignancy in CsA-treated patients. In a multivariate analysis, donor age >60 years, S-creatinine at conversion >2 mg/dl, CMV naïve(-) recipients and immunosuppression with CsA were predictive of an impaired renal function at 36 months. Early conversion to a CNI-free SRL-based immunosuppression is associated with a sustained improvement of renal function up to 36 months after transplantation. Patient selection will be key to derive long-term benefit and avoid treatment failure using this mTOR-inhibitor-based immunosuppressive regimen.

Background: While 4 randomized controlled clinical trials confirmed the early benefits of hypothermic oxygenated machine perfusion (HOPE), high-level evidence regarding long-term clinical outcomes is lacking. The aim of this follow-up study from the HOPE-ECD-DBD trial was to compare long-term outcomes in patients who underwent liver transplantation using extended criteria donor allografts from donation after brain death (ECD-DBD), randomized to either HOPE or static cold storage (SCS). Methods: Between September 2017 and September 2020, recipients of liver transplantation from 4 European centers receiving extended criteria donor-donation after brain death allografts were randomly assigned to HOPE or SCS (1:1). Follow-up data were available for all patients. Analyzed endpoints included the incidence of late-onset complications (occurring later than 6 months and graded according to the Clavien-Dindo Classification and the Comprehensive Complication Index) and long-term graft survival and patient survival. Results: A total of 46 patients were randomized, 23 in both arms. The median follow-up was 48 months (95% CI: 41–55). After excluding early perioperative morbidity, a significant reduction in late-onset morbidity was observed in the HOPE group (median reduction of 23 Comprehensive Complication Index-points [p=0.003] and lower incidence of major complications [Clavien-Dindo ≥3, 43% vs. 85%, p=0.009]). Primary graft loss occurred in 13 patients (HOPE n=3 vs. SCS n=10), resulting in a significantly lower overall graft survival (p=0.029) and adverse 1-, 3-, and 5-year survival probabilities in the SCS group, which did not reach the level of significance (HOPE 0.913, 0.869, 0.869 vs. SCS 0.783, 0.606, 0.519, respectively). Conclusions: Our exploratory findings indicate that HOPE reduces late-onset morbidity and improves long-term graft survival providing clinical evidence to further support the broad implementation of HOPE in human liver transplantation.

Liver resection is a curative treatment for hepatocellular carcinoma (HCC). Tumor-infiltrating leukocytes (TILs) are important players in predicting HCC recurrence. However, the invasive margin could not be confirmed as relevant for HCC. The migration of immune cells into HCC may originate from intratumoral vessels. No previous study has examined perivascular (PV) infiltration. Tumors from 60 patients were examined. Immunohistochemistry was performed against CD3, CD8, CD20, and CD66b. TILs were counted in the PV regions using an algorithm for quantification of the tumor immune stroma (QTiS). The results were correlated with overall (OS) and disease-free survival (DFS), clinical parameters, and laboratory values. PV infiltration of TILs was predominant in resected HCC. Higher PV infiltration of CD3⁺ (p = 0.016) and CD8⁺ (p = 0.028) independently predicted better OS and DFS, respectively. CD20⁺ showed a trend towards better DFS (p = 0.076). Scoring of CD3⁺, CD8⁺, and CD20⁺ independently predicted OS and DFS (p < 0.01). The amount of perivascular-infiltrating CD3⁺ cells is an independent predictor of better OS, and CD8⁺ cells independently predict prolonged DFS. Our novel perivascular infiltration scoring (PVIS) can independently predict both DFS and OS in resected HCC patients.

Background: Due to organ shortage, liver transplantation (LT) in hepatocellular carcinoma (HCC) patients can only be offered subsidiary to other curative treatments, including liver resection (LR). We aimed at developing and validating a machine-learning algorithm (ML) to predict which patients are sufficiently treated by LR. Methods: Twenty-six preoperatively available routine laboratory values along with standard clinical-pathological parameters [including the modified Glascow Prognostic Score (mGPS), the Kings Score (KS) and the Model of Endstage Liver Disease (MELD)] were retrieved from 181 patients who underwent partial LR due to HCC in non-cirrhosis or compensated cirrhosis from January 2007 through March 2018 at our institution. These data were processed using a Random Forest (RF)-based workflow, which included preprocessing, recursive feature elimination (RFE), resampling, training and cross-validation of the RF model. A subset of untouched patient data was used as a test cohort. Basing on the RF prediction, test data could be stratified according to high (HR) or low risk (LR) profile characteristics. Results: RFE analysis provided 6 relevant outcome predictors: mGPS, aPTT, CRP, largest tumor size, number of lesions and age at time of operation. After down-sampling, the predictive value of our model was 0.788 (0.658–0.919) for early DFS. 16.7% of HR and 74.2% of LR patients survived 2 years of follow-up (P<0.001). Conclusions: Our RF model, based solely on clinical parameters, proved to be a powerful predictor of DFS. These results warrant a prospective study to improve the model for selection of suitable candidates for LR as alternative to transplantation. The predictive model is available online: tiny.cc/hcc_model.