Outcomes of 6000 living donor liver transplantation procedures: a pioneering experience at ASAN Medical Center.

Living donor liver transplantation (LDLT) has emerged as a favorable alternative to deceased donor liver transplantation, significantly reducing waitlist mortality, particularly in Asian countries with very low deceased organ donation rates. Asan Medical Center (AMC) in South Korea has pioneered innovative LDLT surgical techniques and become established as an extremely high-volume center for LDLT. This retrospective study analyzed 6000 consecutive LDLT procedures, including 510 dual-graft procedures, performed at AMC between December 1994 and January 2021. Of these, 312 LDLT procedures were performed in children aged < 18 years. In adult recipients, liver cirrhosis (LC) related to viral hepatitis was the most common indication, occurring in 69.8% of cases. Biliary atresia (46.8%) was the most common indication for pediatric LDLT. This study demonstrated outstanding long-term outcomes, with patient survival rates at 1, 5, 10, and 20 years of 92.7%, 85.9%, 82.1%, and 70.9%, respectively, in LDLT group for adults aged 50 and under at the time of LDLT, and 92.9%, 89.0%, 88.1%, and 81.9%, respectively, in the pediatric group. The in-hospital mortality rate of adult recipients was 3.8% (n = 214/5688). This study demonstrates the importance of refined surgical techniques, selection of grafts tailored to the recipient, and comprehensive multidisciplinary perioperative patient care in expanding the scope of LDLT and improving recipient outcomes.

No Prognostic Impact of Graft-to-Recipient Weight Ratio on Hepatocellular Carcinoma Recurrence Following Living Donor Liver Transplantation.

BACKGROUND The effects of a low graft-to-recipient weight ratio (GRWR) on the prognosis of patients with hepatocellular carcinoma (HCC) are unclear. The present study examined whether the GRWR had an impact on the rate of HCC recurrence following living donor liver transplantation (LDLT). MATERIAL AND METHODS This retrospective observational single-center study included 856 patients who underwent LDLT for HCC between January 2006 and December 2016 at Asan Medical Center and evaluated the association between GRWR and post-transplant tumor recurrence. RESULTS Of the 856 patients who underwent LDLT for HCC, 54 (6.3%), 272 (31.8%), 274 (32.0%), and 256 (29.9%) had GRWR <0.8%, 0.8-0.99%, 1.0-1.19%, and ≥1.2%, respectively. Analysis of all patients revealed that the disease-free survival (DFS; P=0.545) and overall survival (OS; P=0.313) rates were not different in these 4 groups. Subgroups analyses also showed that GRWR did not influence survival rates in patients within (DFS: P=0.398; OS: P=0.676) and beyond (DFS: P=0.602; OS: P=0.649) the Milan criteria, or in patients with alpha-fetoprotein-des-γ-carboxyprothrombin-tumor volume scores <5log (DFS: P=0.633; OS: p=0.285) and ≥5log (DFS: P=0.674; OS: P=0.906). CONCLUSIONS GRWR less than 0.8% did not demonstrate a noteworthy prognostic influence on the oncological results among patients who had undergone LDLT for HCC. High-volume multi-center studies are necessary to validate these findings.

Safety of right liver donation after improving steatosis through weight loss in living donors: a retrospective study.

BACKGROUND: Living donor liver transplantation using hepatic steatosis-improved grafts mitigates donor shortage. Herein, we aimed to evaluate the safety and feasibility of right-lobe adult-to-adult living donor liver transplantation using grafts improved through donor weight loss. METHODS: In this retrospective study conducted in a single institution in the Republic of Korea, we reviewed the medical records of living liver donors who lost ≥ 10% of their body weight to improve steatosis before right lobe donation between January 2015 and December 2020. Overall, 1040 right-lobe donors were included, with 150 and 890 donors in the weight loss and control (non-steatosis) groups, respectively. RESULTS: We performed 1:1 individual matching using the greedy matching method, by which 124 patients were included in each group. The median period from the date of the first visit to donation was 113 (interquartile range: 78-184) days in the weight loss group. As body weight changed from 82.8 ± 13.7 kg to 70.8 ± 11.8 kg (p < 0.0001), body mass index also improved from 27.8 ± 3.9 kg/m2 to 23.8 ± 3.1 kg/m2 (p < 0.0001). No significant between-group differences existed in the postoperative laboratory data for living donors and recipients. The incidence of postoperative complications in donors was comparable between the groups (control group, 9.7%; weight loss group, 13.7%; p = 0.3185). The graft and recipient survival rates were comparable between the groups (p = 1.000). CONCLUSION: Weight loss through diet and exercise significantly could improve hepatic steatosis in living donor candidates for liver transplantation, with the surgical outcomes in recipients and donors being equivalent to those in recipients and non-steatotic donors.

Reconstruction of all hepatic arteries in right lobe grafts with 2 hepatic arteries and zero percent hepatic artery thrombosis.

Hepatic artery thrombosis (HAT) is a common cause of graft loss in living-donor liver transplantation, occurring in ~2.5%-8% of patients. Some right lobe grafts have 2 hepatic arteries (HAs), and the optimal reconstruction technique remains controversial. This study aimed to identify risk factors for HAT and to evaluate the efficacy of reconstructing 2 HAs in right lobe grafts. This retrospective, single-center study analyzed 1601 living-donor liver transplantation recipients with a right liver graft and divided them into 1 HA (n = 1524) and 2 HA (n = 77) groups. The reconstruction of all HAs was performed using a microscope with an interrupted suture. The primary outcome was any HAT event. Of the 1601 patients, 37.8% had a history of transcatheter arterial chemoembolization, and 130 underwent pretransplant hepatectomy. Extra-anatomical arterial reconstruction was performed in 38 cases (2.4%). HAT occurred in 1.2% of patients (20/1601) who underwent surgical revascularization. In the multivariate analysis, undergoing pretransplant hepatectomy ( p = 0.008), having a female donor ( p = 0.02), having a smaller graft-to-recipient weight ratio ( p = 0.002), and undergoing extra-anatomical reconstruction ( p = 0.001) were identified as risk factors for HAT. However, having 2 HA openings in right liver grafts was not a risk factor for HAT in our series. Kaplan-Meier survival analysis showed no significant difference in graft survival and patient survival rates between the 1 HA and 2 HA groups ( p = 0.09, p = 0.97). In our series, although the smaller HA in the 2 HA group should increase the risk of HAT, HAT did not occur in this group. Therefore, reconstructing both HAs when possible may be a reasonable approach in living-donor liver transplantation using a right liver graft with 2 HA openings.

Achieving 400 Living Donor Liver Transplantations Annually During the COVID-19 Pandemic: A Single-Center Experience.

BACKGROUND: The COVID-19 pandemic has had a major impact on liver transplantation (LT) and living donor programs globally. PURPOSE: In this study, we aimed to present the principles and strategies of our LT program during the pandemic period and describe its achievements. BASIC PROCEDURES: We retrospectively reviewed the outcomes of 1417 LTs performed at Asan Medical Center, Seoul, Korea, from 2020 to 2022. Of these, 216 recipients who received transplants from deceased donors were excluded, and 1201 recipients who received transplants from 1268 live donors were included in the study, including 38 children <18 years old. MAIN FINDINGS: Among the 1201 living donor LT (LDLT) recipients, the most common indication for LT was unresectable hepatocellular carcinoma (315/1163, 27.1%) in adults and biliary atresia (29/38, 76.3%) in pediatric recipients. Emergency LDLT was performed in 40 patients (3.3%). The median model of end-stage liver disease and pediatric end-stage liver disease scores were 13.9 ± 7.2 and 13.8 ± 7.1, respectively. In-hospital mortality of recipients was higher than usual at 2.2%, but the cause of death was not related to COVID-19 infection. Of the 1268 live donors who underwent hepatectomy for liver donation, 660 (52.1%) underwent hepatectomy using a minimally invasive approach. Although 17 (1.3%) live donors experienced major complications, there were no serious life-threatening complications and no mortality. CONCLUSION: Even in a pandemic era, a team with well-established infection control protocols, patient-tailored surgical strategies, and thorough perioperative care can maintain LDLT at a similar quantitative and qualitative level as in a non-pandemic era.

Reduced Ceramides Are Associated with Acute Rejection in Liver Transplant Patients and Skin Graft and Hepatocyte Transplant Mice, Reducing Tolerogenic Dendritic Cells.

We set up this study to understand the underlying mechanisms of reduced ceramides on immune cells in acute rejection (AR). The concentrations of ceramides and sphingomyelins were measured in the sera from hepatic transplant patients, skin graft mice and hepatocyte transplant mice by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Serum concentrations of C24 ceramide, C24:1 ceramide, C16:0 sphingomyelin, and C18:1 sphingomyelin were lower in liver transplantation (LT) recipients with than without AR. Comparisons with the results of LT patients with infection and cardiac transplant patients with cardiac allograft vasculopathy in humans and in mouse skin graft and hepatocyte transplant models suggested that the reduced C24 and C24:1 ceramides were specifically involved in AR. A ceramide synthase inhibitor, fumonisin B1 exacerbated allogeneic immune responses in vitro and in vivo, and reduced tolerogenic dendritic cells (tDCs), while increased P3-like plasmacytoid DCs (pDCs) in the draining lymph nodes from allogeneic skin graft mice. The results of mixed lymphocyte reactions with ceranib-2, an inhibitor of ceramidase, and C24 ceramide also support that increasing ceramide concentrations could benefit transplant recipients with AR. The results suggest increasing ceramides as novel therapeutic target for AR, where reduced ceramides were associated with the changes in DC subsets, in particular tDCs.

Value of Doppler ultrasonography in predicting clinical outcomes for patients with acute cellular rejection after liver transplantation.

PURPOSE: This study investigated the value of Doppler ultrasonography in predicting clinical outcomes after antirejection treatment for patients with acute cellular rejection (ACR) following liver transplantation (LT). METHODS: This retrospective study included 84 patients who were pathologically diagnosed with ACR and received antirejection treatment within 90 days following LT. Two radiologists searched for abnormal Doppler parameters at ACR diagnosis and within 7 days after antirejection treatment initiation, including portal blood velocity (PBV) <20 cm/s, hepatic artery resistive index <0.5, and a monophasic hepatic vein flow pattern. Interval PBV changes were also evaluated. The frequencies of abnormal Doppler parameters and PBV changes were compared by treatment outcome. RESULTS: The frequency of abnormal PBV in the early post-treatment phase (PBVearly post-treatment) was significantly higher among poor responders (50.0% [10/20]) than among good responders (7.8% [5/64]) (P<0.001). The sensitivity, specificity, and accuracy of abnormal PBVearly post-treatment as a predictor of poor response to antirejection treatment were 50.0% (10/20), 92.2% (59/64), and 82.1% (69/84), respectively. A decrease (>10%) from the PBV at event (PBVevent) to PBVearly post-treatment was significantly more common among poor responders (50.0% [10/20]) than among good responders (20.3% [13/64]) (P=0.019). The sensitivity, specificity, and accuracy of this PBV decrease in predicting poor treatment response were 50.0% (10/20), 79.7% (51/64), and 72.6% (61/84), respectively. CONCLUSION: Abnormal PBVearly post-treatment and a decrease between PBVevent and PBVearly post-treatment were significantly associated with poor treatment response in patients with ACR after LT. Consequently, Doppler ultrasonography may be useful for predicting clinical outcomes in these patients.

Donor sex and donor-recipient sex disparity do not affect hepatocellular carcinoma recurrence after living donor liver transplantation.

Purpose: Studies have yielded contradictory results on whether donor sex and donor-recipient sex disparity affect hepatocellular carcinoma (HCC) recurrence after living donor liver transplantation (LDLT). The present study assessed whether donor sex or donor-recipient sex disparity affects HCC recurrence after LDLT at a high-volume center. Methods: This study included 772 HCC patients who underwent LDLT between January 2006 and December 2015 at Asan Medical Center. Patients were divided into 4 groups based on the sex of the donor and recipient: male-to-male (n = 490, 63.5%), male-to-female (n = 75, 9.7%), female-to-male (n = 170, 22.0%), and female-to-female (n = 37, 4.8%). Results: Disease-free survival (DFS; P = 0.372) and overall survival (OS; P = 0.591) did not differ significantly among the 4 groups. DFS also did not differ significantly between LDLT recipients with male and female donors (P = 0.792) or between male and female recipients (P = 0.084). After patient matching with an α-FP/des-γ-carboxy prothrombin/tumor volume score cutoff of 5logs, donor-recipient sex disparity did not significantly affect DFS (P = 0.598) or OS (P = 0.777). There were also no differences in DFS in matched LDLT recipients with male and female donors (P = 0.312) or between male and female recipients (P = 0.374). Conclusion: Neither donor sex nor donor-recipient sex disparity significantly affected posttransplant HCC recurrence.

Evolution of the technique of renoportal anastomosis for patients with complete portal venous occlusion in living donor liver transplantation: a retrospective cohort study.

BACKGROUND: This study aimed to present our surgical technique and the long-term outcomes of living donor liver transplantations with renoportal anastomosis for patients with complete portal venous occlusion. Renoportal anastomosis (RPA) is a promising technique for portal flow reconstruction during liver transplantation in patients with complete occlusion of the portal vein and extensive splanchnic vein thrombosis. However, reports demonstrating living donor liver transplantations (LDLT) with renoportal anastomosis are rarer than those demonstrating deceased donor liver transplantation. MATERIALS AND METHODS: In this single-centre retrospective cohort study, the authors analyzed the medical records of patients who underwent portal flow reconstruction via RPA with end-to-end anastomosis between the interposition graft and LRV-connected inferior vena cava (VC) cuff. The outcomes included postoperative RPA-related morbidity and patient and allograft survival for patients who underwent LDLT with RPA. RESULTS: Fifteen patients underwent LDLT with portal flow reconstruction via RPA from January 2005 to December 2019. The median follow-up period was 80.7 months (range: 27 days-195.2 months). RPA evolved from end-to-end anastomosis in 1 (6.7%) patient to end-to-side anastomoses in the next 6 (40%) patients and finally, to end-to-end anastomoses between the inferior VC cuff connected to the left renal vein and interposing vascular grafts in 8 (53.3%) patients. After standardization of the RPA technique from the eighth case in 2011, the incidence rate of RPA-related complications significantly decreased from 42.9% (3/7) to 12.5% (1/8). At the last follow-up, all 11 surviving patients had normal liver function, and 10 patients had patent anastomoses on imaging examination. CONCLUSIONS: This standardized RPA technique using an inferior VC cuff connected to the left renal vein creates a safe end-to-end RPA.

Favorable Prognostic Factors for Survival Outcomes of Hepatocellular Carcinoma with Portal Vein Tumor Thrombosis After Hepatectomy.

BACKGROUND: This study aimed to investigate prognostic factors of recurrence and survival associated with hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT). PATIENTS AND METHODS: This retrospective study included 161 patients with HCC with PVTT who underwent hepatectomy between January 2003 and January 2014 at the Asan Medical Center. Regression analyses were conducted to identify favorable predictive factors for overall survival (OS) and recurrence-free survival (RFS). RESULTS: The median follow-up was 15.9 months, while 1-, 3-, and 5-year OS was 65.0%, 38.4%, and 36.0%, respectively, and 1-year RFS was 25.5%. There were no significant differences in OS and RFS between the patients with portal vein invasion (Vp) 1-2 and Vp3-4 PVTT. Patients with intrahepatic recurrence had significantly better overall survival than patients with extrahepatic recurrence. Transcatheter arterial chemoembolization and radiofrequency ablation were the most effective treatments for intrahepatic metastasis, and surgery was the most effective treatment for extrahepatic metastasis. On multivariate analysis, absence of esophageal varices, maximal tumor size < 5 cm, tumor location in single lobe, and anatomical resection were favorable prognostic factors for OS and R0 resection, and absence of microvascular invasion was a favorable prognostic factor for RFS. CONCLUSION: The long-term outcome of patients with HCC with PVTT can be improved under consideration of favorable prognostic factors including absence of esophageal varices, maximal tumor size < 5 cm, tumor location in single lobe, and anatomical resection, R0 resection, and absence of microvascular invasion. In addition, recurrent HCC required aggressive management to prolong overall survival.

Different antibody responses between liver and kidney transplant recipients elicited by third doses of COVID-19 mRNA vaccines.

Background: Solid organ transplant recipients exhibit decreased antibody responses, mainly due to their weakened immune systems. However, data are limited on antibody responses after the primary series of coronavirus disease 2019 (COVID-19) vaccines among recipients of various solid organ transplant types. Thus, we compared the antibody responses after three COVID-19 vaccine doses between liver transplant (LT) and kidney transplant (KT) recipients. Methods: We prospectively enrolled solid organ transplant recipients who received three COVID-19 vaccine doses from June 2021 to February 2022 and measured S1-specific immunoglobulin G antibodies using an enzyme-linked immunosorbent assay. Results: Seventy-six LT and 17 KT recipients were included in the final analysis. KT recipients showed consistently lower antibody responses even after the third vaccine dose (86.2% vs. 52.9%, P=0.008) and lower antibody titers (median, 423.0 IU/mL [interquartile range, 99.6-2,057 IU/mL] vs. 19.7 IU/mL [interquartile range, 6.9-339.4 IU/mL]; P=0.006) than were observed in LT recipients. Mycophenolic acid was a significant risk factor for a seropositive antibody response after the third vaccine dose in the multivariable analysis (odds ratio, 0.06; 95% confidence interval, 0.00-0.39; P=0.02). Conclusions: We found a weaker antibody response despite the completion of the primary series of COVID-19 vaccines in KT recipients than in LT recipients. Mycophenolic acid use in KT recipients might be the main contributor to this observation.

Efficacy and safety of adhesion barrier in living-donor liver transplantation with right liver graft to prevent delayed gastric emptying.

Delayed gastric emptying (DGE) is a common complication of liver transplantation. This study aimed to clarify the efficacy and safety of the application of an adhesion barrier for preventing DGE in living-donor liver transplantation. This retrospective study included 453 patients who underwent living-donor liver transplantation using a right lobe graft between January 2018 and August 2019, and the incidence of postoperative DGE and complications was compared between patients in whom adhesion barrier was used (n=179 patients) and those in whom adhesion barrier was not used (n=274 patients). We performed 1:1 propensity score matching between the 2 groups, and 179 patients were included in each group. DGE was defined according to the International Study Group for Pancreatic Surgery classification. The use of adhesion barrier was significantly associated with a lower overall incidence of postoperative DGE in liver transplantation (30.7 vs. 17.9%; p =0.002), including grades A (16.8 vs. 9.5%; p =0.03), B (7.3 vs. 3.4%; p =0.08), and C (6.6 vs. 5.5%; p =0.50). After propensity score matching, similar results were observed for the overall incidence of DGE (29.6 vs. 17.9%; p =0.009), including grades A (16.8 vs. 9.5%; p =0.04), B (6.7 vs. 3.4%; p =0.15), and C (6.1 vs. 5.0%; p =0.65). Univariate and multivariate analyses showed a significant correlation between the use of adhesion barrier and a low incidence of DGE. There were no statistically significant differences in postoperative complications between the 2 groups. The application of an adhesion barrier could be a safe and feasible method to reduce the incidence of postoperative DGE in living-donor liver transplantation.

Efficacy and safety of lenvatinib in patients with recurrent hepatocellular carcinoma after liver transplantation.

INTRODUCTION: Lenvatinib is approved for the treatment of patients with metastatic or recurrent hepatocellular carcinoma (HCC); however, clinical outcomes of lenvatinib therapy in patients with post-liver transplantation (LT) HCC recurrence remain unclear. We investigated the efficacy and safety of lenvatinib in patients with post-LT HCC recurrence. METHODS: This multinational, multicenter, retrospective study included 45 patients with recurrent HCC after LT who received lenvatinib at six institutions in three countries (Korea, Italy, and Hong Kong) from June 2017 to October 2021. RESULTS: At the time of lenvatinib initiation, 95.6% (n = 43) of patients had Child-Pugh A status, and 35 (77.8%) and 10 (22.2%) participants were classified as having albumin-bilirubin (ALBI) grades 1 and 2, respectively. The objective response rate was 20.0%. With a median follow-up duration of 12.9 months (95% confidence interval [CI]: 11.2-14.7), the median progression-free survival and overall survival (OS) were 7.6 (95% CI: 5.3-9.8) months, and 14.5 (95% CI: 0.8-28.2) months, respectively. Patients with ALBI grade 1 showed significantly better OS (52.3 months, [95% CI: not assessable]) than patients with ALBI grade 2 (11.1 months [95% CI: 0.0-30.4 months], p = 0.003). The most common adverse events were hypertension (n = 25, 55.6%), fatigue (n = 17, 37.8%), and anorexia (n = 14, 31.1%). CONCLUSION: Lenvatinib showed consistent efficacy and toxicity profiles in patients with post-LT HCC recurrence that were comparable to those reported from previous studies among non-LT HCC patients. The baseline ALBI grade correlated with better OS in post-LT lenvatinib-treated patients.

A Multicenter, Randomized, Open-Label Study to Compare the Efficacy and Safety of Tacrolimus and Corticosteroids in Combination With or Without Mycophenolate Mofetil in Liver Transplantation Recipients Infected With Hepatitis B Virus.

BACKGROUND: Mycophenolate mofetil exhibits pharmacologic mechanisms different from calcineurin inhibitors. Therefore, the dose of calcineurin inhibitors can be reduced along with side effects for effective immunosuppression. We aimed to evaluate the efficacy and safety of tacrolimus and corticosteroid in combination with or without mycophenolate mofetil in living donor liver transplantation (LDLT) recipients infected with hepatitis B virus (HBV). METHODS: A randomized, open-label, comparative, multicenter, phase IV study was conducted with 119 patients from January 2014 to September 2017. In the full analysis set population, 58 and 59 patients were included in the study group (triple-drug regimen: TacroBell + My-rept + corticosteroid) and the control group (dual-drug regimen: TacroBell + corticosteroid), respectively. In the per protocol set population, 49 and 42 patients were included in the study and control groups, respectively. RESULTS: In the full analysis set population, the incidence of biopsy-proven acute cellular rejection (rejection activity index score ≥4) was 3.4% in the study group; however, this finding was not observed in the control group (P = .468). Hepatitis B virus recurrence was observed in one patient in the control group. No cases of biopsy-proven acute cellular rejection and HBV recurrence were observed in the per protocol set population. The incidences of serious adverse events were 25.9% and 18.0% in the study and control groups, respectively; however, the difference between the groups was not statistically significant (P = .376). CONCLUSION: Although the study involved a small number of patients, the triple-drug regimen can be considered safe and effective for immunosuppression after living donor liver transplantation in patients infected with HBV.

Incidence of superficial left hepatic vein and its usability for graft hepatic vein venoplasty in pediatric liver transplantation.

BACKGROUNDS: The anatomy of the left hepatic vein (LHV) is variable; thus, it should be considered for graft hepatic vein (GHV) venoplasty for left lateral section (LLS) and left liver grafts. This study assessed the incidence of superficial LHV (sLHV) branches according to LHV anatomy and its usability for GHV venoplasty in pediatric liver transplantation (LT). METHODS: This study consisted of three parts: (1) anatomical classification of LHV variations and the incidence of sLHV branches; (2) morphometric simulative analysis of GHV reconstruction and (3) clinical application based on LHV anatomy. RESULTS: The LHV anatomy of 248 potential LLS graft donors was classified into four types according to the number and location of GHV openings: one single opening (type 1; n = 186 [75.0%]), two large openings (type 2; n = 35 [14.1%]), one large and one small adjacent opening (type 3; n = 14 [5.6%]), and two large widely-separated openings (type 4; n = 13 [5.2%]). An sLHV branch was identified in 87 of 248 (35.1%) donor livers. Morphometric analysis of simulative GHV venoplasty with an sLHV branch increased GHV diameters by 30% in type 1 LLS grafts and 20% in type 2/3 LLS grafts. An analysis of 50 consecutive patients who underwent pediatric LT showed that the 2-year rates of GHV obstruction were 2.0% with LLS grafts and 0% with left liver grafts. CONCLUSIONS: The GHV orifice can be enlarged through LHV anatomy-based unification venoplasty. Unification venoplasty with an sLHV branch provided sufficient enlargement of the GHV orifice.

Cytotoxicity of Human Hepatic Intrasinusoidal Gamma/Delta T Cells Depends on Phospho-antigen and NK Receptor Signaling.

BACKGROUND/AIM: We previously showed that human hepatic intrasinusoidal (HI) natural killer (NK) T cells selectively eliminate hepatocellular carcinoma (HCC) cell lines. In this study, we investigated the underlying mechanisms on how HI γδ T cells, expanded with zoledronate, exhibit a superior cytotoxic effect on HI NK-resistant Huh7 HCC cells. MATERIALS AND METHODS: γδ T cells were obtained from living liver transplant donors or from peripheral blood mononuclear cells (PBMC) of healthy volunteers and were expanded in the presence of IL-2, IL-15, and zoledronate for 2 weeks. Cytotoxicity was measured using the lactate dehydrogenase (LDH) assay in vitro and by flow cytometry using carboxyfluorescein succinimidyl ester (CFSE) in vivo. RESULTS: The cytotoxicity of expanded HI γδ T cells against Huh7 cells was associated with a higher pyrophosphate expression in Huh7 cells compared to SNU398 cells. In contrast, the cytotoxicity of HI γδ T cells against SNU398 cells depended on NKG2D. HI γδ T cells expressed less PD-1 than PB γδ T cells. The cytotoxicity of HI γδ T cells against Du145 and PC3 prostate cancer cells was also associated with pyrophosphate expression in these cells, as well as NKG2D and DNAM-1. CONCLUSION: The expression levels of phospho-antigen in tumor cells determined the cytotoxicity of HI γδ T cells, although the NK activating receptors, death ligands, and immune checkpoint molecules also contribute to their cytotoxicity. γδ T cells are attractive candidates for cancer immune cell therapy.

Cutoff Values for Diagnosing Hepatic Steatosis Using Contemporary MRI-Proton Density Fat Fraction Measuring Methods.

OBJECTIVE: To propose standardized MRI-proton density fat fraction (PDFF) cutoff values for diagnosing hepatic steatosis, evaluated using contemporary PDFF measuring methods in a large population of healthy adults, using histologic fat fraction (HFF) as the reference standard. MATERIALS AND METHODS: A retrospective search of electronic medical records between 2015 and 2018 identified 1063 adult donor candidates for liver transplantation who had undergone liver MRI and liver biopsy within a 7-day interval. Patients with a history of liver disease or significant alcohol consumption were excluded. Chemical shift imaging-based MRI (CS-MRI) PDFF and high-speed T2-corrected multi-echo MR spectroscopy (HISTO-MRS) PDFF data were obtained. By temporal splitting, the total population was divided into development and validation sets. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic performance of the MRI-PDFF method. Two cutoff values with sensitivity > 90% and specificity > 90% were selected to rule-out and rule-in, respectively, hepatic steatosis with reference to HFF ≥ 5% in the development set. The diagnostic performance was assessed using the validation set. RESULTS: Of 921 final participants (624 male; mean age ± standard deviation, 31.5 ± 9.0 years), the development and validation sets comprised 497 and 424 patients, respectively. In the development set, the areas under the ROC curve for diagnosing hepatic steatosis were 0.920 for CS-MRI-PDFF and 0.915 for HISTO-MRS-PDFF. For ruling-out hepatic steatosis, the CS-MRI-PDFF cutoff was 2.3% (sensitivity, 92.4%; specificity, 63.0%) and the HISTO-MRI-PDFF cutoff was 2.6% (sensitivity, 88.8%; specificity, 70.1%). For ruling-in hepatic steatosis, the CS-MRI-PDFF cutoff was 3.5% (sensitivity, 73.5%; specificity, 88.6%) and the HISTO-MRI-PDFF cutoff was 4.0% (sensitivity, 74.7%; specificity, 90.6%). CONCLUSION: In a large population of healthy adults, our study suggests diagnostic thresholds for ruling-out and ruling-in hepatic steatosis defined as HFF ≥ 5% by contemporary PDFF measurement methods.

Treatment patterns for hepatocellular carcinoma in patients with Child-Pugh class B and their impact on survival: A Korean nationwide registry study.

BACKGROUND AND AIMS: There are no established practice guidelines for treating hepatocellular carcinoma (HCC) in patients with Child-Turcotte-Pugh (CTP) class B liver function. To evaluate the impact of various initial treatment modalities on these patients, we conducted a nationwide registry study in Korea. MATERIALS AND METHODS: Treatment patterns and overall survival (OS) of patients with HCC and CTP class B according to initial treatment modalities in each Barcelona Clinic Liver Cancer (BCLC) stage were analysed using data from the Korean Primary Liver Cancer Registry between 2008 and 2016. Initial treatment modalities were categorized as standard, alternative treatment and supportive care only, referring to the 2018 BCLC guidelines, irrespective of liver function. RESULTS: Of the 2318 newly diagnosed Korean patients with HCC and CTP class B, 29.7%, 60.3% and 15.6% of patients in BCLC stages A, B and C, respectively, underwent standard treatment. Adjusted OS hazard ratios of alternative treatment referring to standard treatment were 1.55 (95% confidence interval [CI], 1.25-1.94; p < .001) in BCLC-A, 0.82 (95% CI, 0.43-1.56; p = .550) for curative alternative treatment, 1.89 (95% CI, 0.97-3.68; p = .059) for non-curative alternative treatment in BCLC-B, 0.40 (95% CI, 0.28-0.56; p < .001) for curative alternative treatment, 0.84 (95% CI, 0.69-1.02; p = .076) for non-curative alternative treatment for BCLC-C. CONCLUSION: Regardless of BCLC stages, chemoembolization was conducted the most among patients with CTP class B. Treatment in line with the BCLC treatment algorithm resulted in favourable OS outcomes, except for those with BCLC stage C, as systemic therapy showed poor OS.

Expression Patterns of Tumor Markers in Liver Transplant Recipients Showing Complete Pathological Response of Hepatocellular Carcinoma.

Complete pathological response (CPR) is achieved with various pretransplant locoregional treatments for hepatocellular carcinoma (HCC). This study aimed to investigate pretransplant expression of HCC tumor markers in liver transplantation (LT) recipients showing CPR. For the CPR group, 166 patients were selected from a single-institution LT database. Two control groups of 332 patients without HCC and 184 patients with partial pathological response (PPR) were also selected. The model for end-stage liver disease score in the CPR group was 11.5 ± 7.7. The number of transcatheter arterial chemoembolization sessions before LT was one in 68 patients (14.0%), two in 38 patients (22.9%), and three or more in 60 patients (36.1%). A solitary non-viable tumor was identified in 120 (86.4%) of the explant livers and the largest tumor size was 2.4 ± 1.3 cm. Living-donor and deceased-donor LTs were performed in 152 (91.6%) and 14 (8.4%) patients, respectively. The median levels of α-fetoprotein (AFP) and protein induced by Vitamin K absence or antagonist-II (PIVKA-II) measured within two weeks before LT were 4.2 ng/mL and 20 mAU/mL, respectively. These tumor marker levels were comparable to those in the no-HCC control group, but much lower than those in the PPR group (p < 0.001). Receiver operating characteristic curve analysis of AFP and PIVKA-II showed no definite cutoff values for CPR in the cohort of CPR and no-HCC patients, but significant cutoffs of 6.5 ng/mL for AFP and 29 mAU/mL for PIVKA-II were obtained in the cohort of CPR and PPR patients. The 1-, 3- and 5-year HCC recurrence and overall patient survival rates of the CPR group were 5.1% and 93.3%, 7.6% and 89.6%, and 7.6% and 89.6%, respectively. These tumor recurrence rates were much lower than those in the PPR group (p < 0.001). In conclusion, the present study results suggest that normalizing AFP and PIVKA-II after locoregional treatment is indicative of CPR. However, some CPR patients showed high expression of tumor markers; thus, pretransplant values of HCC tumor markers should be interpreted with caution.