Sequential Normothermic Regional Perfusion and End-ischemic Ex Situ Machine Perfusion Allow the Safe Use of Very Old DCD Donors in Liver Transplantation.

BACKGROUND: In Italy, 20 min of continuous, flat-line electrocardiogram are required for death declaration. Despite prolonged warm ischemia time, Italian centers reported good outcomes in controlled donation after circulatory death (cDCD) liver transplantation by combining normothermic regional and end-ischemic machine perfusion (MP). The aim of this study was to evaluate the safety and feasibility of the use of septuagenarian and octogenarian cDCD donors with this approach. METHODS: All cDCD older than 70 y were evaluated during normothermic regional perfusion and then randomly assigned to dual hypothermic or normothermic MP. RESULTS: In the period from April 2021 to December 2022, 17 cDCD older than 70 y were considered. In 6 cases (35%), the graft was not considered suitable for liver transplantation, whereas 11 (65%) were evaluated and eventually transplanted. The median donor age was 82 y, being 8 (73%) older than 80. Median functional warm ischemia and no-flow time were 36 and 28 min, respectively. Grafts were randomly assigned to ex situ dual hypothermic oxygenated MP in 6 cases (55%) and normothermic MP in 5 (45%). None was discarded during MP. There were no cases of primary nonfunction, 1 case of postreperfusion syndrome (9%) and 2 cases (18%) of early allograft dysfunction. At a median follow-up of 8 mo, no vascular complications or ischemic cholangiopathy were reported. No major differences were found in terms of postoperative hospitalization or complications based on the type of MP. CONCLUSIONS: The implementation of sequential normothermic regional and end-ischemic MP allows the safe use of very old donation after circulatory death donors.

Cholangiocyte Organoids: The New Frontier in Regenerative Medicine for the Study and Treatment of Cholangiopathies.

Cholangiopathies include a group of chronic progressive disorders, affecting the cholangiocytes, the epithelial cells that line the biliary tree, leading to liver parenchymal fibrosis and eventually end-stage liver disease necessitating transplantation. Experimental modeling of these multifactorial cholestatic diseases faces challenges due to the lack of adequate experimental in vitro and in vivo models. A novel approach employs three-dimensional organoid systems that offer several advantages for modeling disease and testing drug response in vitro. Organoids mimic intercellular communication, replicate the architecture of organs, and maintain the cell's original phenotype. Cholangiocyte organoids provide an in vitro model to study the pathogenesis and pharmacotherapeutic treatment of cholangiopathies and show great promise for regenerative therapies. In particular, patient-derived organoids allow personalized medicine approaches and the study of individual disease characteristics. This review highlights the significance of cholangiocyte organoid models in advancing our understanding of cholangiopathies and driving advancements in regenerative medicine strategies.

What Is Hot and New in Basic and Translational Science in Liver Transplantation in 2023? Report of the Basic and Translational Research Committee of the International Liver Transplantation Society.

The 2023 Joint Annual Congress of the International Liver Transplantation Society, European Liver and Intestine Transplant Association, and Liver Intensive Care Group of Europe were held in Rotterdam, the Netherlands, from May 3 to 6, 2023. This year, all speakers were invited to attend the Congress in person for the first time since the COVID-19 pandemic. The congress was attended by 1159 registered delegates from 54 countries representing 5 continents, with the 10 countries comprising the bulk of the delegates. Of the 647 abstracts initially submitted, 542 were eventually presented at the meeting, coming from 38 countries (mainly North America, Europe, and Asia) and 85% of them (462 abstracts) came from only 10 countries. Fifty-three (9.8%) abstracts, originated from 17 countries, were submitted under the Basic/Translational Scientific Research category, a similar percentage as in 2022. Abstracts presented at the meeting were classified as (1) ischemia and reperfusion injury, (2) machine perfusion, (3) bioengineering and liver regeneration, (4) transplant oncology, (5) novel biomarkers in liver transplantation, (6) liver immunology (rejection and tolerance), and (7) artificial intelligence and machine learning. Finally, we evaluated the number of abstracts commented in the Basic and Translational Research Committee-International Liver Transplantation Society annual reports over the past 5 y that resulted in publications in peer-reviewed journals to measure their scientific impact in the field of liver transplantation.

Recipient hepatectomy technique may affect oncological outcomes of liver transplantation for hepatocellular carcinoma.

To date, caval sparing (CS) and total caval replacement (TCR) for recipient hepatectomy in liver transplantation (LT) have been compared only in terms of surgical morbidity. Nonetheless, the CS technique is inherently associated with an increased manipulation of the native liver and later exclusion of the venous outflow, which may increase the risk of intraoperative shedding of tumor cells when LT is performed for HCC. A multicenter, retrospective study was performed to assess the impact of recipient hepatectomy (CS vs. TCR) on the risk of posttransplant HCC recurrence among 16 European transplant centers that used either TCR or CS recipient hepatectomy as an elective protocol technique. Exclusion criteria comprised cases of non-center-protocol recipient hepatectomy technique, living-donor LT, HCC diagnosis suspected on preoperative imaging but not confirmed at the pathological examination of the explanted liver, HCC in close contact with the IVC, and previous liver resection for HCC. In 2420 patients, CS and TCR approaches were used in 1452 (60%) and 968 (40%) cases, respectively. Group adjustment with inverse probability weighting was performed for high-volume center, recipient age, alcohol abuse, viral hepatitis, Child-Pugh class C, Model for End-Stage Liver Disease score, cold ischemia time, clinical HCC stage within Milan criteria, pre-LT downstaging/bridging therapies, pre-LT alphafetoprotein serum levels, number and size of tumor nodules, microvascular invasion, and complete necrosis of all tumor nodules (matched cohort, TCR, n = 938; CS, n = 935). In a multivariate cause-specific hazard model, CS was associated with a higher risk of HCC recurrence (HR: 1.536, p = 0.007). In conclusion, TCR recipient hepatectomy, compared to the CS approach, may be associated with some protective effect against post-LT tumor recurrence.

Concomitant training in robotic and laparoscopic liver resections of low-to-intermediate difficulty score: a retrospective analysis of the learning curve.

In the setting of minimally invasive liver surgery (MILS), training in robotic liver resections (RLR) usually follows previous experience in laparoscopic liver resections (LLR). The aim of our study was to assess the learning curve of RLR in case of concomitant training with LLR. We analyzed consecutive RLRs and LLRs by a surgeon trained simultaneously in both techniques (Surg1); while a second surgeon trained only in LLRs was used as control (Surg2). A regression model was used to adjust for confounders and a Cumulative Sum (CUSUM) analysis was carried out to assess the learning phases according to operative time and difficulty of the procedures (IWATE score). Two-hundred-forty-five procedures were identified (RobSurg1, n = 75, LapSurg1, n = 102, LapSurg2, n = 68). Mean IWATE was 4.0, 4.3 and 5.8 (p < 0.001) in each group. The CUSUM analysis of the adjusted operative times estimated the learning phase in 40 cases (RobSurg1), 40 cases (LapSurg1), 48 cases (LapSurg2); for IWATE score it was 38 cases (RobSurg1), 33 cases (LapSurg1), 38 cases (LapSurg2) respectively. Our preliminary experience showed a similar learning curve of 40 cases for low and intermediate difficulty RLR and LLR. Concomitant training in both techniques was safe and may be a practical option for starting a MILS program.

First-in-human liver transplantation from a centenarian deceased donor after brain death.

Liver transplantation from elderly donors is expanding due to demand for liver grafts, aging of recipients and donors, and introduction of machine perfusion. We report on a liver transplant from a 100-year-old deceased donor after brain death. The liver was transplanted after the use of hypothermic machine perfusion to a 60-year-old recipient with advanced hepatocellular carcinoma undergoing neoadjuvant immunotherapy. Nine months after the transplant, the patient is alive with a functioning graft and no evidence of acute rejection or tumor recurrence.

Liver transplantation with uncontrolled versus controlled DCD donors using normothermic regional perfusion and ex-situ machine perfusion.

In Italy, 20 minutes of continuous, flat-line electrocardiogram are required for death declaration, which significantly increases the risks of donation after circulatory death (DCD) LT. Despite prolonged warm ischemia time, Italian centers reported good outcomes in controlled donation after circulatory death LT by combining normothermic regional and end-ischemic machine perfusion. However, data on uncontrolled DCD (uDCD) LT performed by this approach are lacking. This was a multicenter, retrospective study performed at 3 large-volume centers comparing clinical outcomes of uncontrolled versus controlled DCD LT. The aim of the study was to assess outcomes of sequential normothermic regional perfusion and end-ischemic machine perfusion in uncontrolled DCD liver transplantation (LT). Of 153 DCD donors evaluated during the study period, 40 uDCD and 59 donation after circulatory death grafts were transplanted (utilization rate 52% vs. 78%, p = 0.004). Recipients of uDCD grafts had higher MEAF (4.9 vs. 3.5, p < 0.001) and CCI scores at discharge (24.4 vs. 8.7, p = 0.026), longer ICU stay (5 vs. 4 d, p = 0.047), and a trend toward more severe AKI. At multivariate analysis, 90-day graft loss was associated with recipient BMI and lactate downtrend during normothermic regional perfusion. One-year graft survival was lower in uDCD (75% vs. 90%, p = 0.007) but became comparable when non-liver-related graft losses were treated as censors (77% vs. 90%, p = 0.100). The incidence of ischemic cholangiopathy was 10% in uDCD versus 3% in donation after circulatory death, p = 0.356. uDCD LT with prolonged warm ischemia is feasible by the sequential use of normothermic regional perfusion and end-ischemic machine perfusion. Proper donor and recipient selection are key to achieving good outcomes in this setting.

Challenges With the Implementation of Machine Perfusion in Clinical Liver Transplantation.

Dynamic organ preservation is a relatively old technique which has regained significant interest in the last decade. Machine perfusion (MP) techniques are applied in various fields of solid organ transplantation today. The first clinical series of ex situ MP in liver transplantation was presented in 2010. Since then, the number of research and clinical applications has substantially increased. Despite the notable beneficial effect on organ quality and recipient outcome, MP is still not routinely used in liver transplantation. Based on the enormous need to better preserve organs and the subsequent demand to continuously innovate and develop perfusion equipment further, this technology is also beneficial to test and deliver future therapeutic strategies to livers before implantation. This article summarizes the various challenges observed during the current shift from static to dynamic liver preservation in the clinical setting. The different organ perfusion strategies are discussed first, together with ongoing clinical trials and future study design. The current status of research and the impact of costs and regulations is highlighted next. Factors contributing to costs and other required resources for a worldwide successful implementation and reimbursement are presented third. The impact of research on cost-utility and effectivity to guide the tailored decision-making regarding the optimal perfusion strategy is discussed next. Finally, this article provides potential solutions to the challenging field of innovation in healthcare considering the various social and economic factors and the role of clinical, regulatory, and financial stakeholders worldwide.

Robotic versus laparoscopic liver resections: propensity-matched comparison of two-center experience.

BACKGROUND: The advantages of the robotic approach in minimally invasive liver surgery (MILS) are still debated. This study compares the short-term outcomes between laparoscopic (LLR) and robotic (RLR) liver resections in propensity score matched cohorts. METHODS: Data regarding minimally invasive liver resections in two liver surgery units were retrospectively reviewed. A propensity score matched analysis (1:1 ratio) identified two groups of patients with similar characteristics. Intra- and post-operative outcomes were then compared. The difficulty of MILS was based on the IWATE criteria. RESULTS: Two hundred sixty-nine patients underwent MILS between January 2014 and December 2021 (LLR = 192; RLR = 77). Propensity score matching identified 148 cases (LLR = 74; RLR = 74) consisting of compensated cirrhotic patients (100%) underwent non-anatomic resection of IWATE 1-2 class (90.5%) for a solitary tumor < 5 cm in diameter (93.2%). In such patients, RLRs had shorter operative time (227 vs. 250 min, p = 0.002), shorter Pringle's cumulative time (12 vs. 28 min, p < 0.0001), and less blood loss (137 vs. 209 cc, p = 0.006) vs. LLRs. Conversion rate was nihil (both groups). In RLRs compared to LLRs, R0 rate (93 vs. 96%, p > 0.71) and major morbidity (4.1 vs. 5.4%, p > 0.999) were similar, without post-operative mortality. Hospital stay was shorter in the robotic group (6.2 vs. 6.6, p = 0.0001). CONCLUSION: This study supports the non-inferiority of RLR over LLR. In compensated cirrhotic patients underwent resection of low-to-intermediate difficulty for a solitary nodule < 5 cm, RLR was faster, with less blood loss despite the shorter hilar clamping, and required shorter hospitalization compared to LLR.

A narrative review of intrahepatic cholangiocarcinoma: a surgical curative option.

BACKGROUND AND OBJECTIVE: Cholangiocarcinoma (CCA) is the second commonest primary liver malignancy. Nowadays, the only available treatment with curative intent of intrahepatic cholangiocarcinoma (iCCA) is surgical resection, with a 5-year overall survival (OS) of 25-40%. However, recurrence rate remains high. In this comprehensive review, we describe the newest surgical strategies for iCCA management, including vascular resection, the role of mini-invasive surgery, liver transplant, strategies for future liver remnant augmentation, and the role of neoadjuvant therapies. METHODS: A review of medical databases (PubMed, Scopus and Cochrane Database) was conducted selecting most relevant articles in English language without a specific timeframe. KEY CONTENT AND FINDINGS: Multifocal presentation, vascular, perineural invasion, and lymph nodes involvement are associated with poor outcome. Prognostic factors are being investigated to improve therapeutic approach and outcomes. The role of lymph nodes dissection remains debated. Harvesting at least 6 lymph nodes is recommended to ensure accurate nodal staging. Liver transplantation (LT) recently represented a treatment option only in patients with unresectable early disease (≤2 cm). CONCLUSIONS: Surgical resection remains the only potentially curative treatment for patients with CCA, but continue understanding in diagnosis, operative technique and chemotherapies are changing the landscape in the prognosis. Multicentric and randomized studies are necessaries in the future research with the intent to personalize the treatments, improve patient selection for the resection and reduce recurrence rate.

An extensive evaluation of hepatic markers of damage and regeneration in controlled and uncontrolled donation after circulatory death.

Livers from donations after circulatory death (DCDs) are very sensitive to ischemia/reperfusion injury and thus need careful reconditioning, such as normothermic regional perfusion (NRP). So far, its impact on DCDs has not been thoroughly investigated. This pilot cohort study aimed to explore the NRP impact on liver function by evaluating dynamic changes of circulating markers and hepatic gene expression in 9 uncontrolled DCDs (uDCDs) and 10 controlled DCDs. At NRP start, controlled DCDs had lower plasma levels of inflammatory and liver damage markers, including α-glutathione s-transferase, sorbitol-dehydrogenase, malate dehydrogenase 1, liver-type arginase-1, and keratin-18, but higher levels of osteopontin, sFas, flavin mononucleotide, and succinate than uDCDs. During 4-hour NRP, some damage and inflammatory markers increased in both groups, while IL-6, HGF, and osteopontin increased only in uDCDs. At the NRP end, the tissue expression of early transcriptional regulators, apoptosis, and autophagy mediators was higher in uDCDs than in controlled DCDs. In conclusion, despite initial differences in liver damage biomarkers, the uDCD group was characterized by a major gene expression of regenerative and repair factors after the NRP procedure. Correlative analysis among circulating/tissue biomarkers and the tissue congestion/necrosis degree revealed new potential candidate biomarkers.

New Insights in the Setting of Transplant Oncology.

Background and Objectives: Liver transplantation (LT) is the best strategy for curing several primary and secondary hepatic malignancies. In recent years, growing interest has been observed in the enlargement of the transplant oncology indications. This paper aims to review the most recent developments in the setting of LT oncology, with particular attention to LT for unresectable colorectal liver metastases (CRLM) and cholangiocellular carcinoma (CCA). Materials and Methods: A review of the recently published literature was conducted. Results: Growing evidence exists on the efficacy of LT in curing CRLM and peri-hilar and intrahepatic CCA in well-selected patients when integrating this strategy with (neo)-adjuvant chemotherapy, radiotherapy, or locoregional treatments. Conclusion: For unresectable CCA and CRLM management, several prospective protocols are forthcoming to elucidate LT's impact relative to alternative therapies. Advances in diagnosis, treatment protocols, and donor-to-recipient matching are needed to better define the oncological indications for transplantation. Prospective, multicenter trials studying these advances and their impact on outcomes are still required.

Outcome of liver transplantation in elderly patients: an Italian multicenter case-control study.

Despite the controversial results of liver transplantation (LT) in elderly recipients, the proportion of patients continues to increase. This study investigated the outcome of LT in elderly patients (≥ 65 years) in an Italian, multicenter cohort. Between January 2014 and December 2019, 693 eligible patients were transplanted, and two groups were compared: recipients ≥ 65 years (n = 174, 25.1%) versus 50-59 years (n = 519, 74.9%). Confounders were balanced using a stabilized inverse probability therapy weighting (IPTW). Elderly patients showed more frequent early allograft dysfunction (23.9 versus 16.8%, p = 0.04). Control patients had longer posttransplant hospital stays (median: 14 versus 13 days; p = 0.02), while no difference was observed for posttransplant complications (p = 0.20). At multivariable analysis, recipient age ≥ 65 years was an independent risk factor for patient death (HR 1.76; p = 0.002) and graft loss (HR 1.63; p = 0.005). The 3-month, 1-year, and 5-year patient survival rates were 82.6, 79.8, and 66.4% versus 91.1, 88.5, and 82.0% in the elderly and control group, respectively (log-rank p = 0.001). The 3-month, 1-year, and 5-year graft survival rates were 81.5, 78.7, and 66.0% versus 90.2, 87.2, and 79.9% in the elderly and control group, respectively (log-rank p = 0.003). Elderly patients with CIT > 420 min showed 3-month, 1-year, and 5-year patient survival rates of 75.7%, 72.8%, and 58.5% versus 90.4%, 86.5%, and 79.4% for controls (log-rank p = 0.001). LT in elderly (≥ 65 years) recipients provides favorable results, but inferior to those achieved in younger patients (50-59), especially when CIT > 7 h. Containment of cold ischemia time seems pivotal for favorable outcomes in this class of patients.

Knowledge and irreversibility of cell death: "Nought may endure but mutability".

By using appropriate machine perfusion technologies, such as OrganEx, isolated intact large mammalian brain and other organs, possess the capacity for restoration of microcirculation, and molecular and cellular activity after a prolonged post-mortem interval. We might be ready to critically re-evaluate our concepts and criteria of death under the light of newly acquired knowledge.

The role of sequential normothermic regional perfusion and end-ischemic normothermic machine perfusion in liver transplantation from very extended uncontrolled donation after cardiocirculatory death.

The use of pre-procurement normothermic regional perfusion (NRP) allowed us to implement controlled DCD liver transplantation with results comparable to brain death donors, but the use of uncontrolled DCD is declining due to logistic challenges and the high incidence of post-transplant complications. In Italy, the mandatory stand-off period of 20 min for DCD donors has driven the combined use of NRP and ex-situ machine perfusion with the intent to counterbalance the negative impact of prolonged warm ischemia. Organ viability during NRP is based on duration of warm ischemia, regional perfusion flow, lactate, transaminases values and histology, and those used in Italy are the widest worldwide. However, this evaluation can be difficult, especially when the acute damage is particularly severe. The use of ex-situ NRP could provide a safe organ evaluation. In the period from 06/2020 to 06/2022, all DCD grafts exceeding NRP viability criteria at a single center were eventually evaluated using ex-situ normothermic machine perfusion. Machine perfusion viability criteria were based on lactate clearance, irrespectively to bile production, unless 1-h transaminases perfusate level were not exceeding 5000 IU/L. Three cases of uncontrolled DCD grafts in excess of NRP viability criteria underwent ex-situ graft evaluation. Two matched ex-situ normothermic machine perfusion viability criteria and were successfully transplanted. Both recipients are doing well after 26 and 5 months after surgery with no signs of ischemic cholangiopathy. This experience suggests that the sequential use of NRP and normothermic machine perfusion may further expand the boundaries of organ viability in uncontrolled DCD liver transplantation.

The perioperative period of liver transplantation from unconventional extended criteria donors: data from two high-volume centres.

BACKGROUND: As literature largely focuses on long-term outcomes, this study aimed at elucidating the perioperative outcomes of liver transplant patients receiving a graft from two groups of unconventional expanded criteria donors: brain dead aged > 80 years and cardiac dead. METHODS: Data of 247 cirrhotic patients transplanted at two high volume liver transplant centers were analysed. Confounders were balanced using a stabilized inverse probability therapy weighting and a propensity score for each patient on the original population was generated. The score was created using a multivariate logistic regression model considering a Comprehensive Complication Index ≥ 42 (no versus yes) as the dependent variable and 11 possible clinically relevant confounders as covariate. RESULTS: Forty-four patients received the graft from a cardiac-dead donor and 203 from a brain-dead donor aged > 80 years. Intraoperatively, cardiac-dead donors liver transplant cases required more fresh frozen plasma units (P < 0.0001) with similar reduced need of fibrinogen to old brain-dead donors cases. The incidence of reperfusion syndrome was similar (P = 0.80). In the Intensive Care Unit, both the groups presented a comparable low need for blood transfusions, renal replacement therapy and inotropes. Cardiac-dead donors liver transplantations required more time to tracheal extubation (P < 0.0001) and scored higher Comprehensive Complication Index (P < 0.0001) however the incidence of a severe complication status (Comprehensive Complication Index ≥ 42) was similar (P = 0.52). ICU stay (P = 0.97), total hospital stay (P = 0.57), in hospital (P = 1.00) and 6 months (P = 1.00) death were similar. CONCLUSION: Selected octogenarian and cardiac-dead donors can be used safely for liver transplantation.