Long-Term Outcomes of Recipients of Liver Transplants from Living Donors Treated with a Very Low-Calorie Diet.

The increasing prevalence of steatotic liver disease (SLD) in potential living donors is concerning, as it limits donor's availability amid rising demand. OPTIFAST very low-calorie diet (VLCD), a meal replacement product, effectively reduces weight and hepatic steatosis before transplantation. However, data on the outcomes of recipients of VLCD-treated donors are lacking. We conducted a single-center, retrospective study on 199 living donor liver transplant recipients at Toronto General Hospital, Canada, between January 2015 and January 2020. We compared the 1-year posttransplant outcomes between recipients who received organs from donors treated with VLCD (N = 34) for either weight loss or steatosis reduction, with those who did not require treatment (N = 165). Our analysis revealed no statistically significant differences in the rates of postoperative complications (23% vs 32.4%, p=0.3) or intensive care unit stays (70.9% vs 70.6%, p=1) between recipients of non-VLCD and VLCD grafts. Following adjusted multivariate logistic regression, receipt of VLCD grafts was not associated with increased hospital length of stay. In addition, one-year mortality did not differ between the two groups (4.2% non-VLCD recipients vs 2.9% VLCD recipients, p=0.6). OPTIFAST VLCD treatment for liver donors demonstrates positive and safe outcomes in recipients, expanding the pool of potential living donors for increased organ availability.

Pursuing living donor liver transplantation improves outcomes of patients with autoimmune liver diseases - An intention-to-treat analysis.

Background Living donor liver transplantation (LDLT) offers the opportunity to decrease waitlist time and mortality for patients with AILD; autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC). We compared the survival of patients with a potential live donor (pLDLT) on the waitlist vs. no potential live donor (pDDLT), on an intention-to-treat (ITT) basis. Methods Our retrospective cohort study investigated adults with AILD listed for liver transplant at our program between 2000 and 2021. The pLDLT group comprised recipients with a potential live donor. Otherwise, they were included in the pDDLT group. ITT survival was assessed from the time of listing. Results Of the 533 patients included, 244(43.8%) had a potential living donor. Waitlist dropout was higher for the pDDLT groups among all AILDs (pDDLT 85[29.4%] vs. pLDLT 9[3.7], p<0.001). The 1-, 3- and 5-year ITT survival rates were higher for pLDLT vs. pDDLT among all AILDs (95.7%vs.78.1%, 89.0%vs.70.1%, and 87.1%vs.65.5%, p<0.001). After adjusting for covariates, pLDLT was associated with a 38% reduction in the risk of death among the AILD cohort (HR:0.62, 95%CI:0.42-0.93[p<0.05]), and 60% among the PSC cohort (HR:0.40, 95%CI:0.22-0.74[p<0.05]). There were no differences in the 1-, 3- and 5-year post-transplant survival between LDLT and DDLT (AILD: 95.6%vs.92.1%, 89.9%vs.89.4%, and 89.1%vs. 87.1%, p=0.41). This was consistent after adjusting for covariates (HR: 0.97, 95%CI:0.56-1.68[p>0.9]). Conclusion Our study suggests that having a potential live donor could decrease the risk of death in patients with PSC on the waitlist. Importantly, the post-transplant outcomes in this population are similar between the LDLT and DDLT groups.

A novel model to study mechanisms of cholestasis in human cholangiocytes reveals a role for the SIPR2 pathway.

BACKGROUND: Ductular reactivity is central to the pathophysiology of cholangiopathies. Mechanisms underlying the reactive phenotype activation by exogenous inflammatory mediators and bile acids are poorly understood. METHODS: Using human extrahepatic cholangiocyte organoids (ECOs) we developed an injury model emulating the cholestatic microenvironment with exposure to inflammatory mediators and various pathogenic bile acids. Moreover, we explored roles for the bile acid activated Sphingosine-1-phosphate receptor 2 (S1PR2) and potential beneficial effects of therapeutic bile acids UDCA and norUDCA. RESULTS: Synergistic exposure to bile acids (taurocholic acid, glycocholic acid, glycochenodeoxycholic acid) and TNF-α for 24 hours induced a reactive state as measured by ECO diameter, proliferation, lactate dehydrogenase activity and reactive phenotype markers. While NorUDCA and UDCA treatments given 8 hours after injury induction both suppressed reactive phenotype activation and most injury parameters, proliferation was improved by NorUDCA only. Extrahepatic cholangiocyte organoid stimulation with S1PR2 agonist sphingosine-1-phosphate reproduced the cholangiocyte reactive state and upregulated S1PR2 downstream mediators; these effects were suppressed by S1PR2 antagonist JET-013 (JET), downstream mediator extracellular signal-regulated kinase 1/2 inhibitor, and by norUDCA or UDCA treatments. JET also partially suppressed reactive phenotype after bile acid injury. CONCLUSIONS: We developed a novel model to study the reactive cholangiocyte state in response to pathological stimuli in cholestasis and demonstrated a contributory role of S1PR2 signaling in both injury and NorUDCA/UDCA treatments. This model is a valuable tool to further explore the pathophysiology of human cholangiopathies.

Trajectories of patients relisted for liver transplantation.

INTRODUCTION AND OBJECTIVES: Recurrent cirrhosis complicates 10-30% of Liver transplants (LT) and can lead to consideration for re-transplantation. We evaluated the trajectories of relisted versus primary listed patients on the waitlist using a competing risk framework. MATERIALS AND METHODS: We retrospectively examined 1,912 patients listed for LT at our centre between from 2012 to 2020. Cox proportional hazard models were used to assess overall survival (OS) by listing type and competing risk analysis Fine-Gray models were used to assess cumulative incidence of transplant by listing type. RESULTS: 1,731 patients were included (104 relisted). 44.2% of relisted patients received exception points vs. 19.8% of primary listed patients (p<0.001). Patients relisted without exceptions, representing those with graft cirrhosis, had the worst OS (HR: 4.17, 95%CI 2.63 - 6.67, p=<0.0001) and lowest instantaneous rate of transplant (HR: 0.56, 95%CI 0.38 - 0.83, p=0.006) than primary listed with exception points. On multivariate analysis listing type, height, bilirubin and INR were associated with cumulative incidence of transplant, while listing type, bilirubin, INR, sodium, creatinine were associated with OS. Within relisted patients, there was a trend towards higher mortality (HR: 1.79, 95%CI 0.91 - 3.52, p=0.08) and low transplant incidence (HR: 0.51, 95%CI 0.22 - 1.15, p=0.07) for graft cirrhosis vs other relisting indications. CONCLUSIONS: Patients relisted for LT are carefully curated and comprise a minority of the waitlist population. Despite their younger age, they have worse liver/kidney function, poor waitlist survival, and decreased transplant incidence suggesting the need for early relisting, while considering standardized exception points.

Should advanced donor age be a deterrent in the utilization of grafts from donation after cardiac death in deceased donor liver transplantation? The Toronto experience.

BACKGROUND: Advanced donor age paired with donation after cardiac death (DCD) increases the risk of transplantation, precluding widespread use of grafts from such donors worldwide. Our aim was to analyze outcomes of liver transplantation using grafts from older DCD donors and donation after brain death (DBD) donors. METHODS: Patients who underwent liver transplantation using grafts from deceased donors between January 2016 and December 2021 were included in the study. Short-and long-term outcomes were analyzed for 4 groups of patients: those who received DCD and DBD grafts from younger (< 50 yr) and older (≥ 50 yr) donors. RESULTS: Of the 807 patients included in the analysis, 44.7% (n = 361) of grafts were received from older donors, with grafts for older DCD donors comprising 4.7% of the total cohort (n = 38). Patients who received grafts from older donors had a lower incidence of biliary strictures than those who received grafts from younger donors (7.9% v. 20.0% for DCD donation, p = 0.14, and 4.9% v. 6.8% for DBD donation, p = 0.34), with a significantly lower incidence of ischemic-type biliary strictures in patients who received grafts from older versus younger DCD donors (2.6% v. 18.0%, p = 0.04). There was no difference in 1- and 3-year graft survival rates among patients who received grafts from older and younger DCD donors (92.1% v. 90.8% and 80.2% v. 80.9%, respectively) and those who received grafts from older and younger DBD donors (90.1% v. 93.2% and 85.3% v. 84.4%, respectively) (p = 0.85). Pretransplantation admission to the intensive care unit (hazard ratio [HR] 9.041, p < 0.001) and nonalcoholic steatohepatitis (HR 2.197, p = 0.02) were found to significantly affect survival of grafts from older donors. CONCLUSION: Donor age alone should not be the criterion to determine the acceptability of grafts in liver transplantation. With careful selection criteria, older DCD donors could make a valuable contribution to expanding the liver donor pool, with grafts that produce comparable results to those obtained with standard-criteria grafts.

Loss of zebrafish pkd1l1 causes biliary defects that have implications for biliary atresia splenic malformation.

Biliary atresia is a fibroinflammatory neonatal disease with no effective therapies. A subset of cases (10-20%) is associated with laterality defects - labeled biliary atresia splenic malformation (BASM) syndrome. Recently, whole-exome sequencing of patients with BASM identified deleterious variants in PKD1L1. PKD1L1 is involved in left-right axis determination; however, its role in cholangiocytes is unknown. We generated the pkd1l1hsc117 allele using CRISPR/Cas9 mutagenesis in zebrafish to determine the role of Pkd1l1 in biliary development and function. Wild-type and mutant larvae were assessed for laterality defects, biliary function and biliary tree architecture at 5 days post fertilization. pkd1l1hsc117 mutant larvae exhibited early left-right patterning defects. The gallbladder was positioned on the left in 47% of mutants compared to 4% of wild-type larvae. Accumulation of PED6 in the gallbladder, an indicator of hepatobiliary function, was significantly reduced in pkd1l1hsc117 mutants (46%) compared to wild-type larvae (4%). pkd1l1hsc117 larvae exhibited fewer biliary epithelial cells and reduced density of the intrahepatic biliary network compared to those in wild-type larvae. These data highlight the essential role of pkd1l1 in normal development and function of the zebrafish biliary system, supporting a role for this gene as a cause of BASM.

Toronto Management of Initially Unresectable Liver Metastasis from Colorectal Cancer in a Living Donor Liver Transplant Program.

BACKGROUND: Living donor liver transplantation (LDLT) is an attractive option for patients with unresectable, bilobar colorectal liver metastases (CRLM). However, it is not available in most centers beyond study protocols. This study describes the interim experience with LDLT for CRLM at a large North American transplant and hepatobiliary center. f. STUDY DESIGN: Adults with unresectable CRLM, receiving systemic chemotherapy, were recruited into a prospective clinical trial. Data on demographics, referral patterns, and clinical characteristics were extracted from October 2016 to February 2023. Patients were divided into 3 groups: transplanted, resected, and control (excluded with continuation of systemic chemotherapy). Overall survival and recurrence-free survival were compared. RESULTS: Eighty-one referred patients were assessed for LDLT: 7 received transplants, 22 underwent resection, and 48 were controls. All had similar preassessment baseline characteristics. Median time from initial assessment to transplantation was 15.4 months. The control population had significantly worse postassessment overall survival than the transplanted population (p = 0.002) and resected population (p < 0.001). The median postoperative follow-up duration was 21.4 months (resection) and 14.8 months (LDLT). There was no difference in overall survival between the transplanted and resected populations (1-year 100% vs 93.8%; 3-year 100% vs 43.3%, p = 0.17). However, recurrence-free survival was superior in the LDLT group (1-year 85.7% vs 11.4%; 3-year 68.6% vs 11.4%, p = 0.012). CONCLUSIONS: Most patients with unresectable CRLM referred for LDLT are deemed ineligible for trial inclusion. However, the excellent oncologic outcomes in patients who meet criteria for LDLT supports its role in highly selected populations. Future results after the trial's completion will inform long-term outcomes.

The epidemiology of early deep vein thrombosis in kidney transplant recipients.

BACKGROUND: Because kidney transplant recipients may be at increased risk for deep vein thrombosis (DVT) following transplantation, we investigated the incidence, risk factors, treatments and outcomes of early DVT among kidney transplant recipients. METHODS: An observational, single-centre cohort study was conducted among adult kidney transplant recipients from Jan. 1, 2005, to Dec. 31, 2016 with 1-year followup. Time to DVT was assessed using the Kaplan-Meier method. Cox proportional hazards and linear regression models were used to analyze risk factors for and outcomes of DVT. RESULTS: The cumulative incidence of DVT was 4.25% at 3 months after transplant. In multivariable analysis, the use of depleting induction agents (hazard ratio [HR] 2.13, 95% confidence interval [CI] 1.05-4.35]), white recipient race (HR 1.84. 95% CI 1.08-3.12), the use of kidneys from expanded criteria donors (HR 2.13, 95% CI 1.05-4.32) and lower recipient body mass index (HR 0.95, 95% CI 0.91-1.00) increased the risk for early DVT. Peritransplant DVT prophylaxis was not associated with early DVT. Early DVT was not associated with reduced graft function, death, graft failure or first hospital readmission. CONCLUSION: Risk factors for early DVT in our cohort of kidney transplant recipients included white recipient race, use of depleting agents, lower recipient body mass index and use of expanded criteria donors. As practice patterns of donor and recipient selection in kidney transplantation evolve, the results of this study may aid in perioperative risk assessments and decision-making about the use of DVT prophylaxis.

Prospective evaluation of Gadoxetate-enhanced magnetic resonance imaging and computed tomography for hepatocellular carcinoma detection and transplant eligibility assessment with explant histopathology correlation.

BACKGROUND: We aimed to prospectively compare the diagnostic performance of gadoxetic acid-enhanced MRI (EOB-MRI) and contrast-enhanced Computed Tomography (CECT) for hepatocellular carcinoma (HCC) detection and liver transplant (LT) eligibility assessment in cirrhotic patients with explant histopathology correlation. METHODS: In this prospective, single-institution ethics-approved study, 101 cirrhotic patients were enrolled consecutively from the pre-LT clinic with written informed consent. Patients underwent CECT and EOB-MRI alternately every 3 months until LT or study exclusion. Two blinded radiologists independently scored hepatic lesions on CECT and EOB-MRI utilizing the liver imaging reporting and data system (LI-RADS) version 2018. Liver explant histopathology was the reference standard. Pre-LT eligibility accuracies with EOB-MRI and CECT as per Milan criteria (MC) were assessed in reference to post-LT explant histopathology. Lesion-level and patient-level statistical analyses were performed. RESULTS: Sixty patients (49 men; age 33-72 years) underwent LT successfully. One hundred four non-treated HCC and 42 viable HCC in previously treated HCC were identified at explant histopathology. For LR-4/5 category lesions, EOB-MRI had a higher pooled sensitivity (86.7% versus 75.3%, p <  0.001) but lower specificity (84.6% versus 100%, p <  0.001) compared to CECT. EOB-MRI had a sensitivity twice that of CECT (65.9% versus 32.2%, p <  0.001) when all HCC identified at explant histopathology were included in the analysis instead of imaging visible lesions only. Disregarding the hepatobiliary phase resulted in a significant drop in EOB-MRI performance (86.7 to 72.8%, p <  0.001). EOB-MRI had significantly lower pooled sensitivity and specificity versus CECT in the LR5 category with lesion size < 2 cm (50% versus 79%, p = 0.002 and 88.9% versus 100%, p = 0.002). EOB-MRI had higher sensitivity (84.8% versus 75%, p <  0.037) compared to CECT for detecting < 2 cm viable HCC in treated lesions. Accuracies of LT eligibility assessment were comparable between EOB-MRI (90-91.7%, p = 0.156) and CECT (90-95%, p = 0.158). CONCLUSION: EOB-MRI had superior sensitivity for HCC detection; however, with lower specificity compared to CECT in LR4/5 category lesions while it was inferior to CECT in the LR5 category under 2 cm. The accuracy for LT eligibility assessment based on MC was not significantly different between EOB-MRI and CECT. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03342677 , Registered: November 17, 2017.

Medical Assistance in Dying (MAiD) as a Source of Liver Grafts: Honouring the Ultimate Gift.

OBJECTIVE: To report the clinical outcomes of liver transplants from donors after medical assistance in dying (MAiD) versus donors after cardiac death (DCD) and deceased brain death (DBD). SUMMARY BACKGROUND DATA: In North America, the number of patients needing liver transplants exceeds the number of available donors. In 2016, MAiD was legalized in Canada. METHODS: All patients undergoing deceased donor liver transplantation at Toronto General Hospital between 2016 and 2021 were included in the study. Recipient perioperative and postoperative variables and donor physiological variables were compared among 3 groups. RESULTS: Eight hundred seven patients underwent deceased donor liver transplantation during the study period, including DBD (n=719; 89%), DCD (n=77; 9.5%), and MAiD (n=11; 1.4%). The overall incidence of biliary complications was 6.9% (n=56), the most common being strictures (n=55;6.8%), highest among the MAiD recipients [5.8% (DBD) vs. 14.2% (DCD) vs. 18.2% (MAiD); P =0.008]. There was no significant difference in 1 year (98.4% vs. 96.4% vs. 100%) and 3-year (89.3% vs. 88.7% vs. 100%) ( P =0.56) patient survival among the 3 groups. The 1- and 3- year graft survival rates were comparable (96.2% vs. 95.2% vs. 100% and 92.5% vs. 91% vs. 100%; P =0.37). CONCLUSION: With expected physiological hemodynamic challenges among MAiD and DCD compared with DBD donors, a higher rate of biliary complications was observed in MAiD donors, with no significant difference noted in short-and long-term graft outcomes among the 3 groups. While ethical challenges persist, good initial results suggest that MAiD donors can be safely used in liver transplantation, with results comparable with other established forms of donation.

Long-term outcomes of retransplantation after live donor liver transplantation: A Western experience.

BACKGROUND: Despite most liver transplants in North America being from deceased donors, the number of living donor liver transplants has increased over the last decade. Although outcomes of liver retransplantation after deceased donor liver transplantation have been widely published, outcomes of retransplant after living donor liver transplant need to be further elucidated. METHOD: We aimed to compare waitlist outcomes and survival post-retransplant in recipients of initial living or deceased donor grafts. Adult liver recipients relisted at University Health Network between April 2000 and October 2020 were retrospectively identified and grouped according to their initial graft: living donor liver transplants or deceased donor liver transplant. A competing risk multivariable model evaluated the association between graft type at first transplant and outcomes after relisting. Survival after retransplant waitlisting (intention-to-treat) and after retransplant (per protocol) were also assessed. Multivariable Cox regression evaluated the effect of initial graft type on survival after retransplant. RESULTS: A total of 201 recipients were relisted (living donor liver transplants, n = 67; donor liver transplants, n = 134) and 114 underwent retransplant (living donor liver transplants, n = 48; deceased donor liver transplants, n = 66). The waitlist mortality with an initial living donor liver transplant was not significantly different (hazard ratio = 0.51; 95% confidence interval, 0.23-1.10; P = .08). Both unadjusted and adjusted graft loss risks were similar post-retransplant. The risk-adjusted overall intention-to-treat survival after relisting (hazard ratio = 0.76; 95% confidence interval, 0.44-1.32; P = .30) and per protocol survival after retransplant (hazard ratio:1.51; 95% confidence interval, 0.54-4.19; P = .40) were equivalent in those who initially received a living donor liver transplant. CONCLUSION: Patients requiring relisting and retransplant after either living donor liver transplants or deceased donor liver transplantation experience similar waitlist and survival outcomes.

Prevention and Management of Chronic Postsurgical Pain and Persistent Opioid Use Following Solid Organ Transplantation: Experiences From the Toronto General Hospital Transitional Pain Service.

BACKGROUND: With >700 transplant surgeries performed each year, Toronto General Hospital (TGH) is currently one of the largest adult transplant centers in North America. There is a lack of literature regarding both the identification and management of chronic postsurgical pain (CPSP) after organ transplantation. Since 2014, the TGH Transitional Pain Service (TPS) has helped manage patients who developed CPSP after solid organ transplantation (SOT), including heart, lung, liver, and renal transplants. METHODS: In this retrospective cohort study, we describe the association between opioid consumption, psychological characteristics of pain, and demographic characteristics of 140 SOT patients who participated in the multidisciplinary treatment at the TGH TPS, incorporating psychology and physiotherapy as key parts of our multimodal pain management regimen. RESULTS: Treatment by the multidisciplinary TPS team was associated with significant improvement in pain severity and a reduction in opioid consumption. CONCLUSIONS: Given the risk of CPSP after SOT, robust follow-up and management by a multidisciplinary team should be considered to prevent CPSP, help guide opioid weaning, and provide psychological support to these patients to improve their recovery trajectory and quality of life postoperatively.

Comparison of international guidelines for diagnosis of hepatocellular carcinoma and implications for transplant allocation in liver transplantation candidates with gadoxetic acid enhanced liver MRI versus contrast enhanced CT: a prospective study with liver explant histopathological correlation.

OBJECTIVES: To compare the diagnostic performance of international hepatocellular carcinoma (HCC) guidelines with gadoxetic acid-enhanced MRI (EOB-MRI) and contrast-enhanced Computed tomography (CECT) and their impact on liver transplant (LT) allocation in cirrhotic patients with explant histopathology correlation. METHODS: In this prospective single-centre ethics-approved study, 101 cirrhotic patients were consecutively enrolled with informed consent from the pre-LT clinic. They underwent CECT and EOB-MRI alternately at three monthly intervals until LT or removal from LT list. Two abdominal radiologists, blinded to explant histopathology, independently recorded liver lesions visible on CECT and EOB-MRI. Imaging-based HCC scores were assigned to non-treated liver lesions utilizing Liver Imaging Reporting and Data System (LI-RADS), European Association for the Study of the Liver (EASL), Asian-Pacific Association for the Study of the Liver (APASL) and Korean Liver Cancer Association-National Cancer Center (KLCA) guidelines. Liver explant histopathology was the reference standard. Simulated LT eligibility was assessed as per Milan criteria (MC) in reference to explant histopathology. RESULTS: One hundred and three non-treated HCC and 12 non-HCC malignancy were identified at explant histopathology in 34 patients (29 men, 5 women, age 55-73 years). Higher HCC sensitivities of statistical significance were observed with EOB-MRI for LI-RADS 4 + 5, APASL and KLCA compared to LI-RADS 5 and EASL with greatest sensitivity obtained for LIRADS 4 + 5 lesions. HCC sensitivities by all guidelines with both EOB-MRI and CECT were significantly lower if all histopathology-detected HCCs were included in the analysis, compared to imaging-visible lesions only. A significantly greater variation in HCC sensitivity was noted across the guidelines with EOB-MRI compared to CECT. No significant differences in simulated LT eligibility based on MC were observed across the HCC scoring guidelines with EOB-MRI or CECT. CONCLUSION: HCC sensitivities are variable depending on scoring guideline, lesion size and imaging modality utilised. Prior studies that included only lesions visible on pre-operative imaging overestimate the diagnostic performance of HCC scoring guidelines. Per-lesion differences in HCC diagnosis across these guidelines did not impact patient-level LT eligibility based on MC.

Low utilization of adult-to-adult LDLT in Western countries despite excellent outcomes: International multicenter analysis of the US, the UK, and Canada.

BACKGROUND & AIMS: Adult-to-adult living donor liver transplantation (LDLT) offers an opportunity to decrease the liver transplant waitlist and reduce waitlist mortality. We sought to compare donor and recipient characteristics and post-transplant outcomes after LDLT in the US, the UK, and Canada. METHODS: This is a retrospective multicenter cohort-study of adults (≥18-years) who underwent primary LDLT between Jan-2008 and Dec-2018 from three national liver transplantation registries: United Network for Organ Sharing (US), National Health Service Blood and Transplantation (UK), and the Canadian Organ Replacement Registry (Canada). Patients undergoing retransplantation or multi-organ transplantation were excluded. Post-transplant survival was evaluated using the Kaplan-Meier method, and multivariable adjustments were performed using Cox proportional-hazards models with mixed-effect modeling. RESULTS: A total of 2,954 living donor liver transplants were performed (US: n = 2,328; Canada: n = 529; UK: n = 97). Canada has maintained the highest proportion of LDLT utilization over time (proportion of LDLT in 2008 - US: 3.3%; Canada: 19.5%; UK: 1.7%; p <0.001 - in 2018 - US: 5.0%; Canada: 13.6%; UK: 0.4%; p <0.001). The 1-, 5-, and 10-year patient survival was 92.6%, 82.8%, and 70.0% in the US vs. 96.1%, 89.9%, and 82.2% in Canada vs. 91.4%, 85.4%, and 66.7% in the UK. After adjustment for characteristics of donors, recipients, transplant year, and treating transplant center as a random effect, all countries had a non-statistically significantly different mortality hazard post-LDLT (Ref US: Canada hazard ratio 0.53, 95% CI 0.28-1.01, p = 0.05; UK hazard ratio 1.09, 95% CI 0.59-2.02, p = 0.78). CONCLUSIONS: The use of LDLT has remained low in the US, the UK and Canada. Despite this, long-term survival is excellent. Continued efforts to increase LDLT utilization in these countries may be warranted due to the growing waitlist and differences in allocation that may disadvantage patients currently awaiting liver transplantation. LAY SUMMARY: This multicenter international comparative analysis of living donor liver transplantation in the United States, the United Kingdom, and Canada demonstrates that despite low use of the procedure, the long-term outcomes are excellent. In addition, the mortality risk is not statistically significantly different between the evaluated countries. However, the incidence and risk of retransplantation differs between the countries, being the highest in the United Kingdom and lowest in the United States.

Right Lobe Versus Left Lobe Living Donor Liver Transplantation: A Systematic Review and Meta-analysis of Donor and Recipient Outcomes.

BACKGROUND: Living donor liver transplantation (LDLT) is an established treatment for advanced liver disease. Whether right lobe (RL) or left lobe (LL) LDLT provides the best outcomes for donors and recipients remains contentious. METHODS: MedLine, Embase, PubMed, and Cochrane Central were searched to identify studies comparing RL- and LL-LDLT and reporting donor and/or recipient outcomes. Effect sizes were pooled using random-effect meta-analysis. Meta-regressions were used to explore heterogeneity. RESULTS: Sixty-seven studies were included. RL donors were more likely to experience major complications (relative risk [RR] = 1.63; 95% confidence interval [CI] = 1.30-2.05; I2 = 19%) than LL donors; however, no difference was observed in the risk of any biliary complication (RR = 1.41; 95% CI = 0.91-2.20; I2 = 59%), bile leaks (RR = 1.56; 95% CI = 0.97-2.51; I2 = 52%), biliary strictures (RR = 0.99; 95% CI = 0.43-1.88; I2 = 27%), or postoperative death (RR = 0.51; 95% CI = 0.25-1.05; I2 = 0%). Among recipients, the incidence of major complications (RR = 0.85; 95% CI = 0.68-1.06; I2 = 21%), biliary complications (RR = 1.10; 95% CI = 0.91-1.33; I2 = 8%), and vascular complications (RR = 0.79; 95% CI = 0.44-1.43; I2 = 0%) was similar. Although the rate of small for size syndrome (RR = 0.47; 95% CI = 0.30-0.74; I2 = 0%) and postoperative deaths (RR = 0.62; 95% CI = 0.44-0.87; I2 = 0%) was lower among RL-LDLT recipients, no differences were observed in long-term graft (hazard ratio = 0.87; 95% CI = 0.55-1.38; I2 = 74%) and overall survival (hazard ratio = 0.86; 95% CI = 0.60-1.22; I2 = 44%). CONCLUSIONS: LL donors experience fewer complications than RL donors, and LL-LDLT recipients had similar outcomes to RL-LDLT recipients. These findings suggest that LL-LDLT offers the best outcomes for living donors and similar outcomes for recipients when measures are taken to prevent small for size syndrome.

Recipient and Donor Outcomes After Living-Donor Liver Transplant for Unresectable Colorectal Liver Metastases.

Importance: Colorectal cancer is a leading cause of cancer-related death, and nearly 70% of patients with this cancer have unresectable colorectal cancer liver metastases (CRLMs). Compared with chemotherapy, liver transplant has been reported to improve survival in patients with CRLMs, but in North America, liver allograft shortages make the use of deceased-donor allografts for this indication problematic. Objective: To examine survival outcomes of living-donor liver transplant (LDLT) for unresectable, liver-confined CRLMs. Design, Setting, and Participants: This prospective cohort study included patients at 3 North American liver transplant centers with established LDLT programs, 2 in the US and 1 in Canada. Patients with liver-confined, unresectable CRLMs who had demonstrated sustained disease control on oncologic therapy met the inclusion criteria for LDLT. Patients included in this study underwent an LDLT between July 2017 and October 2020 and were followed up until May 1, 2021. Exposures: Living-donor liver transplant. Main Outcomes and Measures: Perioperative morbidity and mortality of treated patients and donors, assessed by univariate statistics, and 1.5-year Kaplan-Meier estimates of recurrence-free and overall survival for transplant recipients. Results: Of 91 evaluated patients, 10 (11%) underwent LDLT (6 [60%] male; median age, 45 years [range, 35-58 years]). Among the 10 living donors, 7 (70%) were male, and the median age was 40.5 years (range, 27-50 years). Kaplan-Meier estimates for recurrence-free and overall survival at 1.5 years after LDLT were 62% and 100%, respectively. Perioperative morbidity for both donors and recipients was consistent with established standards (Clavien-Dindo complications among recipients: 3 [10%] had none, 3 [30%] had grade II, and 4 [40%] had grade III; donors: 5 [50%] had none, 4 [40%] had grade I, and 1 had grade III). Conclusions and Relevance: This study's findings of recurrence-free and overall survival rates suggest that select patients with unresectable, liver-confined CRLMs may benefit from total hepatectomy and LDLT.

Normothermic Ex Vivo Kidney Perfusion for Human Kidney Transplantation: First North American Results.

BACKGROUND: Normothermic ex vivo kidney perfusion (NEVKP) has shown promising results for preservation, assessment, and reconditioning of kidney allografts in preclinical studies. Here, we report the first North American safety and feasibility study of deceased donor kidneys grafts transplanted following preservation with NEVKP. METHODS: Outcomes of 13 human kidney grafts that received 1 to 3 h of NEVKP after being transported in an anoxic hypothermic machine perfusion device were compared with a matched control group of 26 grafts that were preserved with anoxic hypothermic machine perfusion alone. RESULTS: Grafts were perfused for a median of 171 min (range, 44-275 min). The delayed graft function rate in NEVKP versus control patients was 30.8% versus 46.2% ( P = 0.51). During the 1-y follow-up, no differences in postoperative graft function, measured by serum creatinine, necessity for dialysis, and urine production, were found between the study group and the control group. There were no differences in 1 y posttransplantation graft or patient survival between the 2 groups. CONCLUSIONS: Our study demonstrates the safety and feasibility of NEVKP for human deceased donor kidney transplantation. Further studies are warranted to explore how this technology can minimize cold ischemia, improve posttransplant graft function, and assess and repair expanded criteria kidney grafts.