Long-term outcomes after hypothermic oxygenated machine perfusion and transplantation of 1,202 donor livers in a real-world setting (HOPE-REAL study).

BACKGROUND & AIM: We aimed to assess long-term outcome after transplantation of HOPE-treated donor livers based on real-world data (i.e., IDEAL-D stage 4). METHODS: In this international, multicentre, observational cohort study, we collected data from adult recipients of a HOPE-treated liver transplanted between January 2012 and December 2021. Analyses were stratified for brain-dead (DBD) and circulatory-dead (DCD) donor livers, sub-divided by their respective risk categories. The primary outcome was death-censored graft survival. Secondary outcomes included the incidence of primary non-function (PNF) and ischemic cholangiopathy (IC). RESULTS: We report on 1202 liver transplantations (64% DBD) performed at 22 European centres. For DBD, a total number of 99 benchmark (8%), 176 standard (15%), and 493 extended-criteria (41%) cases were included. For DCD, 117 transplants were classified as low-risk (10%), 186 as high-risk (16%), and 131 as futile (11%), with significant risk profile variations among centres. Actuarial 1-, 3-, and 5-year death-censored graft survival for DBD and DCD was 95%, 92%, and 91%, vs. 92%, 87%, and 81%, respectively (logrank p=0.003). Within DBD and DCD-strata, death-censored graft survival was similar among risk groups (logrank p=0.26, p=0.99). Graft loss due to PNF or IC was 2.3% and 0.4% (DBD), and 5% and 4.1% (DCD). CONCLUSIONS: This study shows excellent 5-year survival after transplantation of HOPE-treated DBD and DCD livers with low rates of graft loss due to PNF or IC, irrespective of their individual risk profile. HOPE-treatment has now reached IDEAL-D stage 4, which further supports the implementation of HOPE in routine clinical practice. IMPACT AND IMPLICATIONS: This study demonstrates the excellent long-term performance of HOPE-treatment of DCD and DBD liver grafts irrespective of their individual risk profile in a real-world setting, outside the evaluation of randomized controlled trials. While previous studies have established safety, feasibility, and efficacy against the current standard, according to the IDEAL-D evaluation framework, HOPE-treatment has now reached the final IDEAL-D Stage 4, which further supports the implementation of HOPE in routine clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05520320.

Beyond histology: A tissue algorithm predictive of post-surgical recurrence in hepatocellular carcinomas, including TERT promoter mutation.

Surgical resection for hepatocellular carcinoma (HCC) is burdened with a high recurrence rate and a lack of reliable prognostic factors. The aim of this study was to integrate the HCC pathological features with gene mutations to improve the prognostic role of pathological analysis. This is a monocentric prospective study, including 67 patients resected for HCC. All clinical data and histological features were collected, including tumor grade, architecture, margins, microvascular invasion, and microscopic portal vascular invasion (MPVI). Next-generation sequencing (NGS) was performed using a laboratory-developed multi-gene panel, allowing to amplify 330 amplicons (21.77 kb), covering the relevant targets for solid tumor analysis. The most represented mutations were TERT promoter (n = 41, 61.2%), TP53 (n = 18, 26.9%) and CTNNB1 (n = 17, 25.4%). At follow-up, 13 (19.4%) patients experienced HCC recurrence: at multivariate analysis, tumor dimensions (p = 0.040), MPVI (p = 0.010), and TERT mutation (p = 0.034) correlated with recurrence. Dimensions ≥ 4.5 cm (very close to AJCC stage pT3; 9 recurrences, p = 0.041, odd-ratio = 3.7), MPVI (9 recurrences, p = 0.062, OR = 3.3), and TERT (11 recurrences, p = 0.049, OR = 4.4) correlated with disease-free survival also at univariate analysis. The concomitant occurrence of these three variables was present in 7 cases, among which 5 recurred (p = 0.002, OR = 15.94). In conclusion, NGS analysis in resected HCC could not only be used for future therapies but should be integrated with histopathology to predict the risk of tumor recurrence after surgical resection: TERT mutation is among the strongest predictors of tumor recurrence, together with tumor stage (dimensions) and the occurrence of MPVI, which should always be reported separately from the classic MVI.

The role of cold ischemia time and hypothermic perfusion in predicting early hepatocellular carcinoma recurrences after liver transplantation.

AIM: The aim of the study was to identify predictors of early tumor recurrence in patients with hepatocellular carcinoma (HCC) after liver transplantation (LT). METHODS: Retrospective cohort study in 237 consecutive liver recipients with HCC between 2016 and 2021. Multivariate logistic analysis was performed to identify predictors of early HCC recurrences. The impact of hypothermic-oxygenated perfusion (HOPE) on outcome was analyzed after propensity score weighting. RESULTS: Early recurrences were observed in 15 cases. Microvascular invasion (OR 3.737, 95% CI 1.246-11.206, p = 0.019) and cold ischemia time (OR 1.155, 95% CI 1.001-1.333, p = 0.049) were independently associated with a lower risk of HCC recurrences. After balancing for relevant variables, patients in the HOPE group had lower rates of tumor recurrence (weighted OR 0.126, 95% CI 0.016-0.989, p = 0.049) and higher recurrence free survival (weighted HR 0.132, 95% CI 0.017-0.999, p = 0.050). CONCLUSION: Reducing cold ischemia time and graft perfusion with HOPE can lead to lower rates of early HCC recurrences and higher recurrence-free survival.

Predictive value of portal fibrosis and inflammation in transplanted liver grafts treated with hypothermic oxygenated perfusion.

BACKGROUND: Hypothermic oxygenated perfusion (HOPE) has become widespread for the preservation of liver grafts, making tangled the relationship among the use of extended criteria donors (ECD), graft histology and transplant outcome. AIMS: To prospectively validate the impact of the graft histology on transplant outcome in recipient receiving liver grafts from ECD after HOPE. METHODS: Ninety-three ECD grafts were prospectively enrolled; 49 (52.7 %) were perfused with HOPE according to our protocols. All clinical, histological and follow-up data were collected. RESULTS: Grafts with portal fibrosis stage ≥ 3 according to Ishak's (evaluated with Reticulin stain) had a significantly higher incidence of early allograft dysfunction (EAD) and 6-month-dysfunction (p = 0.026 and p = 0.049), with more days in Intensive Care Unit (p = 0.050). Lobular fibrosis correlated with post-liver transplant kidney function (p = 0.019). Moderate-to-severe chronic portal inflammation was correlated with graft survival on both multivariate and univariate analyses (p < 0.001), but this risk factor is sensibly reduced by the execution of HOPE. CONCLUSIONS: The use of liver grafts with portal fibrosis stage ≥ 3 implies a higher risk of post-transplant complications. Portal inflammation represents an important prognostic factor as well, but the execution of HOPE represents a valid tool to improve graft survival.

Trophism and Homeostasis of Liver Sinusoidal Endothelial Graft Cells during Preservation, with and without Hypothermic Oxygenated Perfusion.

The aim of the present study was to evaluate the homeostasis and trophism of liver sinusoidal endothelial cells (LSECs) in vivo in different stages of liver graft donation, in order to understand the effects of graft ischemia and perfusion on LSEC activity in liver grafts. Special attention was paid to grafts that underwent hypothermic oxygenated perfusion (HOPE). Forty-seven donors were prospectively enrolled, and two distinct biopsies were performed in each case: one allocation biopsy (at the stage of organ allocation) and one post-perfusion biopsy, performed after graft implant in the recipients. In all biopsies, immunohistochemistry and RT-PCR analyses were carried out for the endothelial markers CD34, ERG, Nestin, and VEGFR-2. We observed an increase in CD34 immunoreactivity in LSEC during the whole preservation/perfusion period (p < 0.001). Nestin and ERG expression was low in allocation biopsies, but increased in post-perfusion biopsies, in both immunohistochemistry and RT-PCR (p < 0.001). An inverse correlation was observed between ERG positivity and donor age. Our results indicate that LSEC trophism is severely depressed in liver grafts, but it is restored after reperfusion in standard conditions. The execution of HOPE seems to improve this recovery, confirming the effectiveness of this machine perfusion technique in restoring endothelial functions.

The role of peritumoral CD8 + /TIA1 + lymphocytes in hepatocellular carcinoma aggressiveness and recurrence after surgical resection.

Hepatocellular carcinoma (HCC) is characterized by a low mutation burden and a relatively low number of tumor-infiltrating lymphocytes (TILs), making still difficult to identify targets for specific therapies. The aim of this study was the identification of the prognostic role of TILs in HCC, focusing on their distribution and status of activation. We retrospectively enrolled 41 patients, undergone to liver resection for HCC. A significant increase of CD8 + intratumoral lymphocytes was observed in HCCs with prevalent solid architecture, but with a higher PD-1/TIA1 ratio, suggesting that HCCs with solid architecture have more peri-tumoral lymphocytes, but with minor functionality. At multivariate and univariate analyses, TIA1/CD8 ratio correlated with tumor recurrence, meaning that HCC with more activated TILs are characterized by a higher tumor aggressiveness. The use of a feasible and cheap immunohistochemical panel can help in post-surgical prognostic stratification, focusing not only in the raw number and density of TILs, but more on their state of activation and morphology.

Hypothermic oxygenated perfusion in extended criteria donor liver transplantation-A randomized clinical trial.

Hypothermic Oxygenated Perfusion (HOPE) of the liver can reduce the incidence of early allograft dysfunction (EAD) and failure in extended criteria donors (ECD) grafts, although data from prospective studies are very limited. In this monocentric, open-label study, from December 2018 to January 2021, 110 patients undergoing transplantation of an ECD liver graft were randomized to receive a liver after HOPE or after static cold storage (SCS) alone. The primary endpoint was the incidence of EAD. The secondary endpoints included graft and patient survival, the EASE risk score, and the rate of graft or other graft-related complications. Patients in the HOPE group had a significantly lower rate of EAD (13% vs. 35%, p = .007) and were more frequently allocated to the intermediate or higher risk group according to the EASE score (2% vs. 11%, p = .05). The survival analysis confirmed that patients in the HOPE group were associated with higher graft survival one year after LT (p = .03, log-rank test). In addition, patients in the SCS group had a higher re-admission and overall complication rate at six months, in particular cardio-vascular adverse events (p = .04 and p = .03, respectively). HOPE of ECD grafts compared to the traditional SCS preservation method is associated with lower dysfunction rates and better graft survival.

Extracellular Vesicles Derived from Mesenchymal Stromal Cells Delivered during Hypothermic Oxygenated Machine Perfusion Repair Ischemic/Reperfusion Damage of Kidneys from Extended Criteria Donors.

The poor availability of kidney for transplantation has led to a search for new strategies to increase the donor pool. The main option is the use of organs from extended criteria donors. We evaluated the effects of hypothermic oxygenated perfusion (HOPE) with and without extracellular vesicles (EV) derived from mesenchymal stromal cells on ischemic/reperfusion injury of marginal kidneys unsuitable for transplantation. For normothermic reperfusion (NR), we used artificial blood as a substitute for red blood cells. We evaluated the global renal ischemic dam-age score (GRS), analyzed the renal ultrastructure (RU), cytochrome c oxidase (COX) IV-1 (a mitochondrial distress marker), and caspase-3 renal expression, the tubular cell proliferation index, hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) tissue levels, and effluent lactate and glucose levels. HOPE+EV kidneys had lower GRS and better RU, higher COX IV-1 expression and HGF and VEGF levels and lower caspase-3 expression than HOPE kidneys. During NR, HOPE+EV renal effluent had lower lactate release and higher glucose levels than HOPE renal effluent, suggesting that the gluconeogenesis system in HOPE+EV group was pre-served. In conclusion, EV delivery during HOPE can be considered a new organ preservation strategy for increasing the donor pool and improving transplant outcome.

Impact of MELD 30-allocation policy on liver transplant outcomes in Italy.

BACKGROUND & AIMS: In Italy, since August 2014, liver transplant (LT) candidates with model for end-stage liver disease (MELD) scores ≥30 receive national allocation priority. This multicenter cohort study aims to evaluate time on the waiting list, dropout rate, and graft survival before and after introducing the macro-area sharing policy. METHODS: A total of 4,238 patients registered from 2010 to 2018 were enrolled and categorized into an ERA-1 Group (n = 2,013; before August 2014) and an ERA-2 Group (n = 2,225; during and after August 2014). A Cox proportional hazards model was used to estimate the hazard ratio (HR) of receiving a LT or death between the two eras. The Fine-Gray model was used to estimate the HR for dropout from the waiting list and graft loss, considering death as a competing risk event. A Fine-Gray model was also used to estimate risk factors of graft loss. RESULTS: Patients with MELD ≥30 had a lower median time on the waiting list (4 vs.12 days, p <0.001) and a higher probability of being transplanted (HR 2.27; 95% CI 1.78-2.90; p = 0.001) in ERA-2 compared to ERA-1. The subgroup analysis on 3,515 LTs confirmed ERA-2 (odds ratio 0.56; 95% CI 0.46-0.68; p = 0.001) as a protective factor for better graft survival rate. The protective variables for lower dropouts on the waiting list were: ERA-2, high-volume centers, no competition centers, male recipients, and hepatocellular carcinoma. The protective variables for graft loss were high-volume center and ERA-2, while MELD ≥30 remained related to a higher risk of graft loss. CONCLUSIONS: The national MELD ≥30 priority allocation was associated with improved patient outcomes, although MELD ≥30 was associated with a higher risk of graft loss. Transplant center volumes and competition among centers may have a role in recipient prioritization and outcomes. CLINICAL TRIAL NUMBER: NCT04530240 LAY SUMMARY: Italy introduced a new policy in 2014 to give national allocation priority to patients with a model for end-stage liver disease (MELD) score ≥30 (i.e. very sick patients). This policy has led to more liver transplants, fewer dropouts, and shorter waiting times for patients with MELD ≥30. However, a higher risk of graft loss still burdens these cases. Transplant center volumes and competition among centers may have a role in recipient prioritization and outcomes.

The Relationship between Timing of Pretransplant Kidney Biopsy, Graft Loss, and Survival in Kidney Transplantation: An Italian Cohort Study.

INTRODUCTION: Kidney biopsy is performed to assess if an extended criteria graft can be used for transplantation. It may be performed before or after cross-clamping during organ procurement. This study aims to evaluate whether the timing of biopsy may modify cold ischemia times (CIT) and/or graft outcomes. METHODS: Kidney transplants performed in our center from January 2007 to December 2017 were analyzed. Grafts with preimplantation kidney biopsy were included. Biopsies were performed during surgical back table (ex situ kidney biopsy [ESKB]) until 2012 and since then before the aortic cross-clamping (in situ kidney biopsy [ISKB]). To overcome biases owing to different distributions, a propensity score model was developed. The study population consists in 322 patients, 115 ESKB, and 207 ISKB. RESULTS: CIT was significantly lower for ISKB (730 min ISKB vs. 840 min ESKB, p value = 0.001). In both crude (OR 0.27; 95% confidence interval, 95% CI 0.12-0.60; p value = 0.002) and adjusted analyses (OR 0.37; 95% CI 0.14-0.94; p value = 0.039), ISKB was associated with a reduced odd of graft loss when compared to ESKB. DISCUSSION/CONCLUSION: Performing preimplantation kidney biopsy during the recovery, prior to the aortic cross-clamping, may be a strategy to reduce CIT and improve transplant outcomes.

Normothermic with or without hypothermic oxygenated perfusion for DCD before liver transplantation: European multicentric experience.

Grafts from donors with cardiac death (DCD) are subject to warm ischemia time (WIT) due to the no-touch-period (20 min in Italy and 5 min in France). These livers (LT) have higher rates of early allograft dysfunction (EAD), primary non-function (PNF), and ischemic cholangiopathy (IC) compared to LT from brain dead donors (DBD). Normothermic regional perfusion (NRP) is a beneficial strategy to mitigate organ damage; a further approach is the application of ex vivo hypothermic oxygenated perfusion (HOPE) after cold storage (CS). We retrospectively analyzed LTs performed from 2016 to 2019 at three transplant centers using NRP-DCD grafts: Bologna and Milan treated with HOPE (group A), Rennes preserved using CS (group B). No-flow period, total and functional WIT were significantly higher in group A than in group B (30.5±7.7 vs. 20.5±4.1; 56.5±20.4 vs. 39.1±21.6; 41.9±12.5 vs. 25.5±3.7; respectively, P < .05), without differences in the postoperative course. In particular, the two groups had similar rates of EAD (21.1% vs. 25.0%), PNF (5.3% vs. 6.3%), IC (0% vs. 12.5%, P = .112), and non-IC biliary complications (0% vs. 6.3%, P = .457), re-LT (10.5% vs.12.5%). This occurred despite a high rate of UK DCD risk score > 10 (63.2% A vs. 17.6% B, P = .000), which theoretically would make a large number of these transplants "futile." In conclusion, Italian and French groups had similar post-LT outcomes, probably related to the use of HOPE after CS in the case of long WIT.

The Role of Ex Situ Hypothermic Oxygenated Machine Perfusion and Cold Preservation Time in Extended Criteria Donation After Circulatory Death and Donation After Brain Death.

Hypothermic oxygenated machine perfusion (HOPE) has the potential to counterbalance the detrimental consequences of cold and warm ischemia time (WIT) in both donation after brain death (DBD) and donation after circulatory death (DCD). Herein we investigated the protective effects of HOPE in extended criteria donor (ECD) DBD and overextended WIT DCD grafts. The present retrospective case series included 50 livers subjected to end-ischemic HOPE or dual DHOPE in 2 liver transplantation (LT) centers from January 2018 to December 2019. All DCD donors were subjected to normothermic regional perfusion before organ procurement. Results are expressed as median (interquartile range [IQR]). In the study period, 21 grafts were derived from overextended WIT DCD donors (total WIT 54 [IQR, 40-60] minutes and 75% classified as futile), whereas 29 were from ECD DBD. A total of 3 biliary complications and 1 case of ischemia-type biliary lesion were diagnosed. The rate of early allograft dysfunction (EAD) was 20%, and those patients had higher Comprehensive Complication Index scores. Through a changing point analysis, cold preservation time >9 hours was associated with prolonged hospital stays (P = 0.02), higher rates of EAD (P = 0.009), and worst post-LT complications (P = 0.02). Logistic regression analyses indicated a significant relationship between cold preservation time and EAD. No differences were shown in terms of the early post-LT results between LTs performed with DCD and DBD. Overall, our data are fully comparable with benchmark criteria in LT. In conclusion, the application of DHOPE obtained satisfactory and promising results using ECD-DBD and overextended DCD grafts. Our findings indicate the need to reduce cold preservation time also in the setting of DHOPE, particularly for grafts showing poor quality.

Complex Liver Transplantation Using Venovenous Bypass With an Atypical Placement of the Portal Vein Cannula.

In liver transplantation (LT) medical literature, venovenous bypass (VVB) with the interposition of a venous graft attached to the inferior mesenteric vein (IMV) or to the splenic vein (SV) has not been reported previously. Here, we report the decompression of the portomesenteric compartment in 2 patients with complex cases of orthotopic LT. A femoroaxillary percutaneous VVB was installed prior to abdominal opening to decompress massive collateral veins in the abdominal wall. In the first patient, the IMV was connected to a donor vein graft with a lateroterminal anastomosis, and the distal part of the vein graft was cannulated and connected to the VVB. In the second patient, because of the excessive size of the spleen, it was necessary to perform a splenectomy to gain sufficient space in the abdomen to implant the new liver. The SV was connected to a donor vein graft with a terminoterminal anastomosis, and the distal part of the vein graft was cannulated and connected to the VVB. In both patients, the decompression of the portomesenteric compartment was crucial to reduce portal hypertension and to access the hepatic hilum, where the dissection was very complex due to previous major surgeries. In conclusion, VVB with the interposition of a venous graft attached to the IMV or to the SV during LT is a safe and simple technique, and it may be useful for patients needing VVB with no standard access to the portal compartment, particularly in the case of severe portal hypertension and re-LTs.

Heterotopic segmental liver transplantation on splenic vessels after splenectomy with delayed native hepatectomy after graft regeneration: A new technique to enhance liver transplantation.

We describe a patient with liver metastases from colorectal cancer treated with chemotherapy and hepatic resection, who developed unresectable multifocal liver recurrence and who received liver transplantation using a novel planned technique: heterotopic transplantation of segment 2-3 in the splenic fossa with splenectomy and delayed hepatectomy after regeneration of the transplanted graft. We transplanted a segmental liver graft after in-situ splitting without any impact on the waiting list, as it was previously rejected for pediatric and adult transplantation. The volume of the graft was insufficient to provide liver function to the recipient, so we performed this novel operation. The graft was anastomosed to the splenic vessels after splenectomy, and the native liver portal flow was modulated to enhance graft regeneration, leaving the native recipient liver intact. The volume of the graft doubled during the next 2 weeks and the native liver was removed. After 8 months, the patient lives with a functioning liver in the splenic fossa and without abdominal tumor recurrence. This is the first case reported of a segmental graft transplanted replacing the spleen and modulating the portal flow to favor graft growth, with delayed native hepatectomy.