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.

Cavoportal Hemitransposition in Liver Transplantation: Toward a More Safe and Efficient Technique.

Extended splanchnic venous thrombosis represents a challenge for the liver transplantation (LT) surgeon. In the absence of large venous tributaries, the cavoportal hemitransposition (CPHTr) and the combined liver-intestinal or multivisceral transplantation are the only technical solutions. Because of the reported high morbidity and mortality rates due to infrequent use and a lack of standardization, the former technique has been almost abandoned by the transplant community. A newly designed technique of CPHTr is presented that is based on the combination of an inferior vena cava (IVC)-sparing hepatectomy and large laterolateral cavocaval and end-to-side cavoportal anastomoses separated only by a double vascular stapler line. This technique allows the splanchnic blood to be completely diverted toward the allograft and to eliminate low-flow IVC areas, which possibly lead to complications. The modified CPHTr technique proposed here offers a valuable alternative to much more complex and invasive intestinal transplantation procedures.

Gut microbiome analysis as a tool towards targeted non-invasive biomarkers for early hepatocellular carcinoma.

OBJECTIVE: To characterise gut microbiome in patients with hepatocellular carcinoma (HCC) and evaluate the potential of microbiome as non-invasive biomarkers for HCC. DESIGN: We collected 486 faecal samples from East China, Central China and Northwest China prospectively and finally 419 samples completed Miseq sequencing. We characterised gut microbiome, identified microbial markers and constructed HCC classifier in 75 early HCC, 40 cirrhosis and 75 healthy controls. We validated the results in 56 controls, 30 early HCC and 45 advanced HCC. We further verified diagnosis potential in 18 HCC from Xinjiang and 80 HCC from Zhengzhou. RESULTS: Faecal microbial diversity was increased from cirrhosis to early HCC with cirrhosis. Phylum Actinobacteria was increased in early HCC versus cirrhosis. Correspondingly, 13 genera including Gemmiger and Parabacteroides were enriched in early HCC versus cirrhosis. Butyrate-producing genera were decreased, while genera producing-lipopolysaccharide were increased in early HCC versus controls. The optimal 30 microbial markers were identified through a fivefold cross-validation on a random forest model and achieved an area under the curve of 80.64% between 75 early HCC and 105 non-HCC samples. Notably, gut microbial markers validated strong diagnosis potential for early HCC and even advanced HCC. Importantly, microbial markers successfully achieved a cross-region validation of HCC from Northwest China and Central China. CONCLUSIONS: This study is the first to characterise gut microbiome in patients with HCC and to report the successful diagnosis model establishment and cross-region validation of microbial markers for HCC. Gut microbiota-targeted biomarkers represent potential non-invasive tools for early diagnosis of HCC.

Longterm results of liver transplantation from donation after circulatory death.

Donation after circulatory death (DCD) liver transplantation (LT) may imply a risk for decreased graft survival, caused by posttransplantation complications such as primary nonfunction or ischemic-type biliary lesions. However, similar survival rates for DCD and donation after brain death (DBD) LT have been reported. The objective of this study is to determine the longterm outcome of DCD LT in the Eurotransplant region corrected for the Eurotransplant donor risk index (ET-DRI). Transplants performed in Belgium and the Netherlands (January 1, 2003 to December 31, 2007) in adult recipients were included. Graft failure was defined as either the date of recipient death or retransplantation whichever occurred first (death-uncensored graft survival). Mean follow-up was 7.2 years. In total, 126 DCD and 1264 DBD LTs were performed. Kaplan-Meier survival analyses showed different graft survival for DBD and DCD at 1 year (77.7% versus 74.8%, respectively; P = 0.71), 5 years (65.6% versus 54.4%, respectively; P = 0.02), and 10 years (47.3% versus 44.2%, respectively; P = 0.55; log-rank P = 0.038). Although there was an overall significant difference, the survival curves almost reach each other after 10 years, which is most likely caused by other risk factors being less in DCD livers. Patient survival was not significantly different (P = 0.59). Multivariate Cox regression analysis showed a hazard ratio of 1.7 (P < 0.001) for DCD (corrected for ET-DRI and recipient factors). First warm ischemia time (WIT), which is the time from the end of circulation until aortic cold perfusion, over 25 minutes was associated with a lower graft survival in univariate analysis of all DCD transplants (P = 0.002). In conclusion, DCD LT has an increased risk for diminished graft survival compared to DBD. There was no significant difference in patient survival. DCD allografts with a first WIT > 25 minutes have an increased risk for a decrease in graft survival. Liver Transplantation 22 1107-1114 2016 AASLD.

Semi-xenotransplantation: the regenerative medicine-based approach to immunosuppression-free transplantation and to meet the organ demand.

Although xenografts have always held immeasurable potential as an inexhaustible source of donor organs, immunological barriers and physiological incompatibility have proved to be formidable obstacles to clinical utility. An exciting, new regenerative medicine-based approach termed "semi-xenotransplantation" (SX) seeks to overcome these obstacles by combining the availability and reproducibility of animal organs with the biocompatibility and functionality of human allografts. Compared to conventional xenotransplantation wherein the whole organ is animal-derived, SX grafts are cleansed of their antigenic cellular compartment to produce whole-organ extracellular matrix scaffolds that retain their innate structure and vascular channels. These scaffolds are then repopulated with recipient or donor human stem cells to generate biocompatible semi-xenografts with the structure and function of native human organs. While numerous hurdles must be still overcome in order for SX to become a viable treatment option for end-stage organ failure, the immense potential of SX for meeting the urgent needs for a new source of organs and immunosuppression-free transplantation justifies the interest that the transplant community is committing to the field.

Belgian multicenter experience with intestinal transplantation.

Intestinal transplantation (ITx) has evolved from an experimental procedure toward a clinical reality but remains a challenging procedure. The aim of this survey was to analyze the multicenter Belgian ITx experience. From 1999 to 2014, 24 ITx in 23 patients were performed in Belgium, divided over five centers. Median recipient age was 38 years (8 months-57 years); male/female ratio was 13/10; six were children; and 17 adults. Intestinal failure was related to intestinal ischemia (n = 5), volvulus (n = 5), splanchnic thrombosis (n = 4), Crohn (n = 2), pseudo-obstruction (n = 2), microvillus inclusion (n = 2), Churg-Strauss (n = 1), necrotizing enterocolitis (n = 1), intestinal atresia (n = 1), and chronic rejection (n = 1). Graft type was isolated ITx (n = 9), combined liver-ITx (n = 11) and multivisceralTx (n = 4). One was a living donor-related transplantation and five patients received simultaneously a kidney graft. Early acute rejection occurred in 8; late acute rejection in 4; and chronic rejection in 2. Two patients developed a post-transplant lymphoproliferative disease. Nine patients have died. Among 14 survivors at last follow-up, 11 have been transplanted for more than 1 year. None of the latter has developed renal failure, and all were nutritionally independent with a Karnofsky score > 90%. One-/five-year patient and graft survivals were 71.1%, 62.8%, 58.7% and 53.1%, respectively. Based on this experience, ITx has come of age in Belgium as a lifesaving and potentially quality of life restoring therapy.

Is minimal, [almost] steroid-free immunosuppression a safe approach in adult liver transplantation? Long-term outcome of a prospective, double blind, placebo-controlled, randomized, investigator-driven study.

OBJECTIVE: To investigate the safety of minimal immunosuppression (IS) in liver transplantation (LT). BACKGROUND: The lack of long-term follow-up studies, including pathologic data, has led to a protean handling of IS in LT. METHODS: Between February 2000 and September 2004, 156 adults were enrolled in a prospective, randomized, double-blind, placebo-controlled minimization trial comparing tacrolimus placebo (TAC-PLAC) and TAC short-term steroid (TAC-STER) IS. All patients had a minimum clinical, biochemical, and histological follow-up of 5 years. RESULTS: Five-year actual patient and graft survival rates in TAC-PLAC and TAC-STER groups were 78.1% and 82.1% (P=0.89) and 74.2% and 76.9% (P=0.90), respectively. Five-year biopsies were available in 112 (89.6%) of 125 survivors. Twelve patients refused a biopsy because of their excellent evolution; tissue material was insufficient in 1 patient; 11 had normal liver tests; and 2 patients had developed alcoholic and secondary biliary cirrhosis. Histology was normal in 44 (39.3%) patients; 35 (31.3%) had disease recurrence. The remaining biopsies showed nonspecific chronic hepatitis (14.3%), mild inflammatory infiltrates (10.7%), and steatosis (3.5%). All findings were equally distributed between both groups. In each group, 3 patients (4.8%) presented with acute cellular rejection after the first year and only 1 (0.9%) TAC-PLAC patient developed chronic rejection after IS withdrawal because of pneumonitis. Arterial hypertension, diabetes mellitus, renal insufficiency, hypercholesterolemia, gout, and obesity were equally low in both groups. CONCLUSIONS: Excellent long-term results can be obtained under minimal IS and absence of steroids. TAC-based monotherapy is feasible in most adult liver recipients until 5 years of follow-up.

Hepatocellular cancer: how to expand safely inclusion criteria for liver transplantation.

PURPOSE OF REVIEW: The Milan criteria are still considered to be the best ones to select patients with hepatocellular cancer (HCC) for liver transplantation. Although the Milan criteria allowed lowering the incidence of tumor recurrence to a remarkable 10%, there is growing evidence that high numbers of patients were unrightfully excluded from a curative liver transplantation when exceeding these criteria. New strategies have been advocated during recent years with the intent not only to enlarge the number of potential transplant candidates, but also to select recipients with the lowest biological risk of recurrence. RECENT FINDINGS: Different 'biological' and 'dynamic' parameters have been proposed both in western and eastern scenarios, such as α-fetoprotein dynamics, radiological response to locoregional treatments and several inflammatory markers, the neutrophil-to-lymphocyte ratio being the most promising one. SUMMARY: The paradigm that HCC patients should be selected according to morphological aspects (tumor numbers and diameters) only, based on the almost 20-year old success story of the Milan criteria, should be modified by combining these parameters with newer biological tumor markers in order to further refine the selection for liver transplantation. Such therapeutic algorithm will allow to further improve selection for and thus outcome after liver transplantation for HCC patients.

Liver transplantation for metastatic liver malignancies.

PURPOSE OF REVIEW: Liver transplantation is a validated treatment of primary hepatobiliary tumours. Over the last decade, a renewed interest for liver transplantation as a curative treatment of colorectal liver metastasis (CR-LM) and neuro-endocrine metastasis (NET-LM) has developed. RECENT FINDINGS: The ELTR and UNOS analyses showed that liver transplantation may offer excellent disease-free survival (ranging from 30 to 77%) in case of NET-LM, on the condition that stringent selection criteria are implemented. The interest for liver transplantation in the treatment of CR-LM has been fostered by the Norwegian SECA study. Five-year A 5-year survival rate of 60% could be reached. Despite the high recurrence rate (90%), one-third of patients were disease free following pulmonary surgery for metastases. SUMMARY: Liver transplantation will take a more prominent place in the therapeutic algorithm of CR-LM and NET-LM. Larger experiences are necessary to improve knowledge about tumour biology and to refine selection criteria. A multimodal approach adding neo and adjuvant medical treatment to the transplant procedure will be key to bring this oncologic transplant project into the clinical arena. The preserved liver function in these patients will allow a more deliberate access to split liver and living donation for these indications.

Cell and organ bioengineering technology as applied to gastrointestinal diseases.

This review illustrates promising regenerative medicine technologies that are being developed for the treatment of gastrointestinal diseases. The main strategies under validation to bioengineer or regenerate liver, pancreas, or parts of the digestive tract are twofold: engineering of progenitor cells and seeding of cells on supporting scaffold material. In the first case, stem cells are initially expanded under standard tissue culture conditions. Thereafter, these cells may either be delivered directly to the tissue or organ of interest, or they may be loaded onto a synthetic or natural three-dimensional scaffold that is capable of enhancing cell viability and function. The new construct harbouring the cells usually undergoes a maturation phase within a bioreactor. Within the bioreactor, cells are conditioned to adopt a phenotype similar to that displayed in the native organ. The specific nature of the scaffold within the bioreactor is critical for the development of this high-function phenotype. Efforts to bioengineer or regenerate gastrointestinal tract, liver and pancreas have yielded promising results and have demonstrated the immense potential of regenerative medicine. However, a myriad of technical hurdles must be overcome before transplantable, engineered organs become a reality.

Prognostic Factors for 10-Year Survival in Patients With Hepatocellular Cancer Receiving Liver Transplantation.

Background: Long-term survival after liver transplantation (LT) for hepatocellular cancer (HCC) continues to increase along with the modification of inclusion criteria. This study aimed at identifying risk factors for 5- and 10-year overall and HCC-specific death after LT. Methods: A total of 1,854 HCC transplant recipients from 10 European centers during the period 1987-2015 were analyzed. The population was divided in three eras, defined by landmark changes in HCC transplantability indications. Multivariable logistic regression analyses were used to evaluate the significance of independent risk factors for survival. Results: Five- and 10-year overall survival (OS) rates were 68.1% and 54.4%, respectively. Two-hundred forty-two patients (13.1%) had HCC recurrence. Five- and 10-year recurrence rates were 16.2% and 20.3%. HCC-related deaths peaked at 2 years after LT (51.1% of all HCC-related deaths) and decreased to a high 30.8% in the interval of 6 to 10 years after LT. The risk factors for 10-year OS were macrovascular invasion (OR = 2.71; P = 0.001), poor grading (OR = 1.56; P = 0.001), HCV status (OR = 1.39; P = 0.001), diameter of the target lesion (OR = 1.09; P = 0.001), AFP slope (OR = 1.63; P = 0.006), and patient age (OR = 0.99; P = 0.01). The risk factor for 10-year HCC-related death were AFP slope (OR = 4.95; P < 0.0001), microvascular (OR = 2.13; P < 0.0001) and macrovascular invasion (OR = 2.32; P = 0.01), poor tumor grading (OR = 1.95; P = 0.001), total number of neo-adjuvant therapies (OR = 1.11; P = 0.001), diameter of the target lesion (OR = 1.11; P = 0.002), and patient age (OR = 0.97; P = 0.001). When analyzing survival rates in function of LT era, a progressive improvement of the results was observed, with patients transplanted during the period 2007-2015 showing 5- and 10-year death rates of 26.8% and 38.9% (vs. 1987-1996, P < 0.0001; vs. 1997-2006, P = 0.005). Conclusions: LT generates long-term overall and disease-free survival rates superior to all other oncologic treatments of HCC. The role of LT in the modern treatment of HCC becomes even more valued when the follow-up period reaches at least 10 years. The results of LT continue to improve even when prudently widening the inclusion criteria for transplantation. Despite the incidence of HCC recurrence is highest during the first 5 years post-transplant, one-third of them occur later, indicating the importance of a life-long follow-up of these patients.

Immunosuppression in liver and intestinal transplantation.

Immunosuppression handling plays a key role in the early and long-term results of transplantation. The development of multiple immunosuppressive drugs led to numerous clincial trials searching to reach the ideal regimen. Due to heterogeneity of the studied patient cohorts and flaws in many, even randomized controlled, study designs, the answer still stands out. Nowadays triple-drug immunosuppression containing a calcineurin inhibitor (preferentially tacrolimus), an antimetabolite (using mycophenolate moffettil or Azathioprine) and short-term steroids with or without induction therapy (using anti-IL2 receptor blocker or anti-lymphocytic serum) is the preferred option in both liver and intestinal transplantation. This chapter aims, based on a critical review of the definitions of rejection, corticoresistant rejection and standard immunosuppression to give some reflections on how to reach an optimal immunosuppressive status and to conduct trials allowing to draw solid conclusions. Endpoints of future trials should not anymore focus on biopsy proven, acute and chronic, rejection but also on graft and patient survival. Correlation between early- and long-term biologic, immunologic and histopathologic findings will be fundamental to reach in much more patients the status of operational tolerance.

A prospective randomised, open-labeled, trial comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing liver transplantation for hepatocellular carcinoma.

BACKGROUND: The potential anti-cancer effects of mammalian target of rapamycin (mTOR) inhibitors are being intensively studied. To date, however, few randomised clinical trials (RCT) have been performed to demonstrate anti-neoplastic effects in the pure oncology setting, and at present, no oncology endpoint-directed RCT has been reported in the high-malignancy risk population of immunosuppressed transplant recipients. Interestingly, since mTOR inhibitors have both immunosuppressive and anti-cancer effects, they have the potential to simultaneously protect against immunologic graft loss and tumour development. Therefore, we designed a prospective RCT to determine if the mTOR inhibitor sirolimus can improve hepatocellular carcinoma (HCC)-free patient survival in liver transplant (LT) recipients with a pre-transplant diagnosis of HCC. METHODS/DESIGN: The study is an open-labelled, randomised, RCT comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing LT for HCC. Patients with a histologically confirmed HCC diagnosis are randomised into 2 groups within 4-6 weeks after LT; one arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol and the second arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol for the first 4-6 weeks, at which time sirolimus is initiated. A 21/2 -year recruitment phase is planned with a 5-year follow-up, testing HCC-free survival as the primary endpoint. Our hypothesis is that sirolimus use in the second arm of the study will improve HCC-free survival. The study is a non-commercial investigator-initiated trial (IIT) sponsored by the University Hospital Regensburg and is endorsed by the European Liver and Intestine Transplant Association; 13 countries within Europe, Canada and Australia are participating. DISCUSSION: If our hypothesis is correct that mTOR inhibition can reduce HCC tumour growth while simultaneously providing immunosuppression to protect the liver allograft from rejection, patients should experience less post-transplant problems with HCC recurrence, and therefore could expect a longer and better quality of life. A positive outcome will likely change the standard of posttransplant immunosuppressive care for LT patients with HCC. TRIAL REGISTER: Trial registered at http://www.clinicaltrials.gov: NCT00355862(EudraCT Number: 2005-005362-36).

Liver transplantation and vascular tumours.

Based on analysis of the literature and of the audited ELITA (European Liver Intestinal Transplant Association)-ELTR (European Liver Transplant Registry) data, the place of liver transplantation (LT) in the treatment of vascular tumours is discussed. Hepatic epithelioid haemangioendothelioma has currently become a good indication for LT with 5- and 10-year post-LT patient survival rates of 83% and 74% respectively and 5- and 10-year recurrence-free survival rates of 82% and 64% respectively. In contrast, the results of LT for haemangiosarcoma (HAS) are disastrous with an universal tumour recurrence within 6 months and no single patient survival after 2 years. Therefore, HAS remains an absolute contraindication to LT. The value of LT in the treatment of infantile haemangioendothelioma is more difficult to evaluate because of the very reduced number of reported cases and because of the often difficult differential diagnosis with angiosarcoma. LT should be reserved to those children not responding to medical treatment on the condition that sarcomatous modifications are excluded by expert pathologists to avoid a futile transplant procedure.

Hepatic Epithelioid Hemangioendothelioma and Adult Liver Transplantation: Proposal for a Prognostic Score Based on the Analysis of the ELTR-ELITA Registry.

BACKGROUND: Hepatic epithelioid hemangioendothelioma (HEHE) is a rare vascular tumor which has an intermediate aggressive behavior. Although the value of liver transplantation (LT) is well established, its place in the management of HEHE is still unclear. The aim of this study is to confirm, based on a very large patient cohort, the value of LT in the management of HEHE and to identify risk factors for post-LT recurrence. METHODS: The outcome of 149 transplant recipients with HEHE recorded in the European Liver Transplant Registry during the period November 1984 to May 2014 was analyzed. Median post-LT follow-up was 7.6 years (interquartile range, 2.8-14.4). RESULTS: Cox regression analysis showed that macrovascular invasion (hazard ratio [HR], 4.8; P < 0.001), pre-LT waiting time of 120 days or less (HR, 2.6; P = 0.01) and hilar lymph node invasion (HR = 2.2; P = 0.03), but not pre-LT extrahepatic disease, were significant risk factors for recurrence. These findings, which were also confirmed in a propensity score analysis, allowed the development of a HEHE-LT score enabling stratification of patients in relation to their risk of tumor recurrence. Patients with a score of 2 or less had a much better 5-year disease-free survival compared to those having a score of 6 or higher (93.9% vs 38.5%; P < 0.001). CONCLUSIONS: The analysis of this (largest in the world) HEHE adult liver recipient cohort clearly confirms the value of LT in the treatment of this rare disorder and also permits identification of patients at risk of posttransplant recurrence. Posttransplant follow-up should take the HEHE-LT score into account. Extrahepatic disease localization is reconfirmed not to be a contraindication for LT.