Comprehensive deep learning-based assessment of living liver donor CT angiography: from vascular segmentation to volumetric analysis.

BACKGROUND: Precise preoperative assessment of liver vasculature and volume in living donor liver transplantation is essential for donor safety and recipient surgery. Traditional manual segmentation methods are being supplemented by deep learning (DL) models, which may offer more consistent and efficient volumetric evaluations. METHODS: This study analyzed living liver donors from Samsung Medical Center using preoperative CT angiography data between April 2022 and February 2023. A DL-based 3D residual U-Net model was developed and trained on segmented CT images to calculate the liver volume and segment vasculature, with its performance compared to traditional manual segmentation by surgeons and actual graft weight. RESULTS: The DL model achieved high concordance with manual methods, exhibiting Dice Similarity Coefficients of 0.94±0.01 for the right lobe and 0.91±0.02 for the left lobe. The liver volume estimates by DL model closely matched those of surgeons, with a mean discrepancy of 9.18 mL, and correlated more strongly with actual graft weights (R-squared value of 0.76 compared to 0.68 for surgeons). CONCLUSION: The DL model demonstrates potential as a reliable tool for enhancing preoperative planning in liver transplantation, offering consistency and efficiency in volumetric assessment. Further validation is required to establish its generalizability across various clinical settings and imaging protocols.

Analgesic effects of ultrasound-guided preoperative posterior Quadratus Lumborum block in laparoscopic hepatectomy: A prospective double-blinded randomized controlled trial.

STUDY OBJECTIVE: To determine if single-injection bilateral posterior quadratus lumborum block (QLB) with ropivacaine would improve postoperative analgesia in the first 24 h after laparoscopic hepatectomy, compared with 0.9% saline. DESIGN: Prospective, double blinded, randomized controlled trial. SETTING: A single tertiary care center from November 2021 and January 2023. PATIENTS: A total of 94 patients scheduled to undergo laparoscopic hepatectomy due to hepatocellular carcinoma. INTERVENTIONS: Ninety-four patients were randomized into a QLB group (receiving 20 mL of 0.375% ropivacaine on each side, 150 mg in total) or a control group (receiving 20 mL of 0.9% saline on each side). MEASUREMENTS: The primary outcome was the cumulative opioid consumption during the initial 24-h post-surgery. Secondary outcomes included pain scores and intraoperative and recovery parameters. MAIN RESULTS: The mean cumulative opioid consumption during the initial 24-h post-surgery was 30.8 ± 22.4 mg in the QLB group (n = 46) and 34.0 ± 19.4 mg in the control group (n = 46, mean differences: -3.3 mg, 95% confidence interval, -11.9 to 5.4, p = 0.457). The mean resting pain score at 1 h post-surgery was significantly lower in the QLB group than in the control group (5 [4-6.25] vs. 7 [4.75-8], p = 0.035). No significant intergroup differences were observed in the resting or coughing pain scores at other time points or in other secondary outcomes. CONCLUSIONS: Preoperative bilateral posterior QLB did not reduce cumulative opioid consumption during the first 24 h after laparoscopic hepatectomy.

Surgical outcome and risk scoring to predict survival after hepatic resection for hepatocellular carcinoma with portal vein tumor thrombosis.

Backgrounds/Aims: The hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) is classified as the advanced stage (BCLC stage C) with extremely poor prognosis, and in current guidelines is recommended for systemic therapy. This study aimed to evaluate the surgical outcomes and long-term prognosis after hepatic resection (HR) for patients who have HCC combined with PVTT. Methods: We retrospectively analyzed 332 patients who underwent HR for HCC with PVTT at ten tertiary referral hospitals in South Korea. Results: The median overall and recurrence-free survival after HR were 32.4 and 8.6 months, while the 1-, 3-, and 5-year overall survival rates were 75%, 48%, and 39%, respectively. In multivariate analysis, tumor number, tumor size, AFP, PIVKA-II, neutrophil-to-lymphocyte ratio, and albumin-bilirubin (ALBI) grade were significant prognostic factors. The risk scoring was developed using these seven factors-tumor, inflammation and hepatic function (TIF), to predict patient prognosis. The prognosis of the patients was well stratified according to the scores (log-rank test, p < 0.001). Conclusions: HR for patients who have HCC combined with PVTT provided favorable survival outcomes. The risk scoring was useful in predicting prognosis, and determining the appropriate treatment strategy for those patients who have HCC with PVTT.

Prognostic significance of MRI features in patients with solitary large hepatocellular carcinoma following surgical resection.

OBJECTIVE: To assess the prognostic impact of preoperative MRI features on outcomes for single large hepatocellular carcinoma (HCC) (≥ 8 cm) after surgical resection. MATERIAL AND METHODS: This retrospective study included 151 patients (mean age: 59.2 years; 126 men) with a single large HCC who underwent gadoxetic acid-enhanced MRI and surgical resection between 2008 and 2020. Clinical variables, including tumor markers and MRI features (tumor size, tumor margin, and the proportion of hypovascular component on hepatic arterial phase (AP) (≥ 50% vs. < 50% tumor volume) were evaluated. Cox proportional hazards model analyzed overall survival (OS), recurrence-free survival (RFS), and associated factors. RESULTS: Among 151 HCCs, 37.8% and 62.2% HCCs were classified as ≥ 50% and < 50% AP hypovascular groups, respectively. The 5- and 10-year OS and RFS rates in all patients were 62.0%, 52.6% and 41.4%, 38.5%, respectively. Multivariable analysis revealed that ≥ 50% AP hypovascular group (hazard ratio [HR] 1.7, p = 0.048), tumor size (HR 1.1, p = 0.006), and alpha-fetoprotein ≥ 400 ng/mL (HR 2.6, p = 0.001) correlated with poorer OS. ≥ 50% AP hypovascular group (HR 1.9, p = 0.003), tumor size (HR 1.1, p = 0.023), and non-smooth tumor margin (HR 2.1, p = 0.009) were linked to poorer RFS. One-year RFS rates were lower in the ≥ 50% AP hypovascular group than in the < 50% AP hypovascular group (47.4% vs 66.9%, p = 0.019). CONCLUSION: MRI with ≥ 50% AP hypovascular component and larger tumor size were significant factors associated with poorer OS and RFS after resection of single large HCC (≥ 8 cm). These patients require careful multidisciplinary management to determine optimal treatment strategies. CLINICAL RELEVANCE STATEMENT: Preoperative MRI showing a ≥ 50% arterial phase hypovascular component and larger tumor size can predict worse outcomes after resection of single large hepatocellular carcinomas (≥ 8 cm), underscoring the need for tailored, multidisciplinary treatment strategies. KEY POINTS: MRI features offer insights into the postoperative prognosis for large hepatocellular carcinoma. Hypovascular component on arterial phase ≥ 50% and tumor size predicted poorer overall survival and recurrence-free survival. These findings can assist in prioritizing aggressive and multidisciplinary approaches for patients at risk for poor outcomes.

Left lobe living donor liver transplantation using the resection and partial liver segment 2-3 transplantation with delayed total hepatectomy (RAPID) procedure in cirrhotic patients: First case report in Korea.

In liver transplantation, the primary concern is to ensure an adequate future liver remnant (FLR) volume for the donor, while selecting a graft of sufficient size for the recipient. The living donor-resection and partial liver segment 2-3 transplantation with delayed total hepatectomy (LD-RAPID) procedure offers a potential solution to expand the donor pool for living donor liver transplantation (LDLT). We report the first case involving a cirrhotic patient with autoimmune hepatitis and hepatocellular carcinoma, who underwent left lobe LDLT using the LD-RAPID procedure. The living liver donor (LLD) underwent a laparoscopic left hepatectomy, including middle hepatic vein. The resection on the recipient side was an extended left hepatectomy, including the middle hepatic vein orifice and caudate lobe. At postoperative day 7, a computed tomography scan showed hypertrophy of the left graft from 320 g to 465 mL (i.e., a 45.3% increase in graft volume body weight ratio from 0.60% to 0.77%). After a 7-day interval, the diseased right lobe was removed in the second stage surgery. The LD-RAPID procedure using left lobe graft allows for the use of a small liver graft or small FLR volume in LLD in LDLT, which expands the donor pool to minimize the risk to LLD by enabling the donation of a smaller liver portion.

3D auto-segmentation of biliary structure of living liver donors using magnetic resonance cholangiopancreatography for enhanced preoperative planning.

BACKGROUND: This study aimed to develop an automated segmentation system for biliary structures using a deep learning model, based on data from magnetic resonance cholangiopancreatography (MRCP). MATERIALS AND METHODS: Living liver donors who underwent MRCP using the gradient and spin echo technique followed by three-dimensional modeling were eligible for this study. A three-dimensional residual U-Net model was implemented for the deep learning process. Data were divided into training and test sets at a 9:1 ratio. Performance was assessed using the dice similarity coefficient to compare the model's segmentation with the manually labeled ground truth. RESULTS: The study incorporated 250 cases. There was no difference in the baseline characteristics between the train set (n=225) and test set (n=25). The overall mean Dice Similarity Coefficient was 0.80±0.20 between the ground truth and inference result. The qualitative assessment of the model showed relatively high accuracy especially for the common bile duct (88%), common hepatic duct (92%), hilum (96%), right hepatic duct (100%), and left hepatic duct (96%), while the third-order branch of the right hepatic duct (18.2%) showed low accuracy. CONCLUSION: The developed automated segmentation model for biliary structures, utilizing MRCP data and deep learning techniques, demonstrated robust performance and holds potential for further advancements in automation.

Comparison between laparoscopic liver resection and open liver resection in patients with hepatocellular carcinoma with portal vein tumor thrombosis.

BACKGROUND: Recently, the outcomes of surgical treatment for advanced hepatocellular carcinoma (HCC) have improved. However, despite the technical advancements in laparoscopic liver resection (LLR), it is still not recommended as the standard treatment for HCC with portal vein tumor thrombosis (PVTT) because of the poor oncological outcomes. This study aims to compare the clinical outcomes of open liver resection (OLR) and LLR in patients with HCC with PVTT. METHODS: A total of 86 patients with PVTT confirmed in the pathological report between January 2014 and December 2018, were enrolled. Short-term, postoperative, and long-term outcomes, including recurrence-free survival and overall survival rates, were evaluated. RESULTS: No difference between the two groups, except for age, was detected. The median age in the laparoscopic group was significantly higher than that in the open group. Regarding the pathological features, the maximal tumor size was significantly larger in the OLR; other pathological factors did not differ. There was no significant difference between overall survival (OS) and recurrence-free survival (RFS). Vp3 PVTT (hazards ratio [HR] 6.1, 95% confidence interval [CI] 1.9-18.5), Edmondson grade IV (HR 4.7, 95% CI 1.7-12.9, p = 0.003), and intrahepatic metastasis (HR 3.9, 95% CI 2.1-7.2, p < 0.001) remained the unique independent predictors of recurrence-free survival according to a multivariate Cox proportional hazard regression analysis. CONCLUSIONS: Laparoscopic liver resection for the management of HCC with PVTT provides the same short- and long-term results as those of the open approach.

Laparoscopic liver resection as a treatment option for intrahepatic cholangiocarcinoma.

Laparoscopic liver resection (LLR) remains controversial in the treatment of intrahepatic cholangiocarcinoma (ICC). The aim of the present study is to investigate the outcomes of LLR for ICC compared to open liver resection (OLR). We retrospectively reviewed patients who underwent surgery for ICC between January 2013 and February 2020. OLR and LLR were compared after propensity score matching (PSM). Overall survival (OS) and recurrence-free survival (RFS) were compared between the matched groups. During the study period, 219 patients met the inclusion criteria (OLR = 170 patients, 77.6%; LLR = 49 patients, 22.4%). Two groups of 43 patients each were analyzed after PSM. The 5-year RFS and OS were 44.6% and 47.9% in the OLR group and 50.9% and 39.8% in the LLR group, respectively. Hospital stay and intensive care unit care were significantly shorter and lower in the LLR group than in the OLR group, respectively. Total postoperative complications and complication rates for those Clavien-Dindo grade 3 or higher were similar between the OLR group and the LLR group. Multiple tumors and lymph node metastases were predisposing factors for tumor recurrence and death in multivariate analysis. The present study suggests that LLR should be considered in selective ICC because of short hospitalization and similar oncologic outcome and overall survival.

Liver resection in selective hepatocellular carcinoma with Vp3 or Vp4 portal vein tumor thrombosis improves prognosis.

BACKGROUND/AIM: Hepatocellular carcinoma (HCC) tumor thrombi located in the first branch of the portal vein (Vp3) or in the main portal trunk (Vp4) are associated with poor prognosis. This study aimed to investigate the clinicopathological characteristics and risk factors for HCC recurrence and mortality following liver resection (LR) in patients with Vp3 or Vp4 HCC. METHODS: The study included 64 patients who underwent LR for HCC with Vp3 or Vp4 portal vein tumor thrombosis (PVTT). RESULTS: Fifty-eight patients (90.6%) had Vp3 PVTT, whereas the remaining six patients exhibited Vp4 PVTT. The median tumor size measured 8 cm, with approximately 36% of patients presented with multiple tumors. Fifty-four patients (84.4%) underwent open LR, whereas 10 patients underwent laparoscopic LR. In the Vp4 cases, combined LR and tumor thrombectomy were performed. The 3-year cumulative disease-free survival rate was 42.8% for the Vp3 group and 22.2% for the Vp4 group. The overall survival (OS) rate at 3 years was 47.9% for the Vp3 group and 60.0% for the Vp4 group. Intrahepatic metastasis has been identified as an important contributor to HCC recurrence. High hemoglobin levels are associated with high mortality. CONCLUSION: LR is a safe and effective treatment modality for selected patients with Vp3 or Vp4 HCC PVTT. This suggests that LR is a viable option for these patients, with favorable outcomes in terms of OS.

Recurrence-free Survival After Liver Transplantation Versus Surgical Resection for Hepatocellular Carcinoma: Role of High-risk MRI Features.

BACKGROUND: This study aimed to evaluate recurrence-free survival (RFS) and overall survival (OS) after liver transplantation (LT) or liver resection (LR) for hepatocellular carcinoma (HCC) and perform subgroup analysis for HCC with high-risk imaging findings for recurrence on preoperative liver magnetic resonance imaging (MRI; high-risk MRI features). METHODS: We included patients with HCC eligible for both LT and LR and received either of the treatments between June 2008 and February 2021 from 2 tertiary referral medical centers after propensity score-matching. RFS and OS were compared between LT and LR using Kaplan-Meier curves with the log-rank test. RESULTS: Propensity score-matching yielded 79 patients in the LT group and 142 patients in the LR group. High-risk MRI features were noted in 39 patients (49.4%) in the LT group and 98 (69.0%) in the LR group. The Kaplan-Meier curves for RFS and OS were not significantly different between the 2 treatments among the high-risk group (RFS, P = 0.079; OS, P = 0.755). Multivariable analysis showed that treatment type was not a prognostic factor for RFS and OS ( P = 0.074 and 0.937, respectively). CONCLUSIONS: The advantage of LT over LR for RFS may be less evident among patients with high-risk MRI features.

LI-RADS category is associated with treatment outcomes of small single HCC: surgical resection vs. radiofrequency ablation.

OBJECTIVES: To assess whether the Liver Imaging Reporting and Data System (LI-RADS) category is associated with the treatment outcomes of small single hepatocellular carcinoma (HCC) after surgical resection (SR) and radiofrequency ablation (RFA). METHODS: This retrospective study included 357 patients who underwent SR (n = 209) or RFA (n = 148) for a single HCC of ≤ 3 cm between 2014 and 2016. LI-RADS categories were assigned. Overall survival (OS), recurrence-free survival (RFS), and local tumor progression (LTP) rates after treatment were compared according to the LI-RADS category (LR-4/5 vs. LR-M) before and after propensity score matching (PSM). Prognostic factors for treatment outcomes were assessed. RESULTS: In total, 357 patients (mean age, 59 years; men, 272) with 357 HCCs (294 LR-4/5 and 63 LR-M) were included. After PSM (n = 78 in each treatment group), there were 10 and 11 LR-M HCCs in the SR and RFA group, respectively. There were no significant differences in OS or RFS. However, SR provided a lower 5-year LTP rate than RFA (1.4% vs. 14.9%, p = 0.001). SR provided a lower 5-year LTP rate than RFA for LR-M HCCs (0% vs. 34.4%, p = 0.062) and LR-4/5 HCCs (1.5% vs. 12.0%, p = 0.008). The LI-RADS category was the sole risk factor associated with poor OS (hazard ratio [HR] 3.79, p = 0.004), RFS (HR 2.12; p = 0.001), and LTP (HR 2.89; p = 0.032). CONCLUSION: LI-RADS classification is associated with the treatment outcome of HCC, supporting favorable outcomes of SR over RFA for LTP, especially for HCCs categorized as LR-M. CLINICAL RELEVANCE STATEMENT: Liver Imaging Reporting and Data System category has a potential prognostic role, supporting favorable outcomes of surgical resection over radiofrequency ablation for local tumor progression, especially for hepatocellular carcinoma categorized as LR-M. KEY POINTS: • SR provided a lower 5-year LTP rate than RFA for HCCs categorized as LR-M (0% vs. 34.4%, p = 0.062) and HCCs categorized as LR-4/5 (1.5% vs. 12.0%, p = 0.008). • There is a steeply increased risk of LTP within 1 year after RFA for LR-M HCCs, compared to SR. • The LI-RADS category was the sole risk factor associated with poor OS (HR 3.79, p = 0.004), RFS (HR 2.12; p = 0.001), and LTP (HR 2.89; p = 0.032) in patients with HCC of ≤ 3 cm treated with SR or RFA.

Preoperative assessment of microvascular invasion risk using gadoxetate-enhanced MRI for predicting outcomes after liver transplantation for single hepatocellular carcinoma within the Milan criteria.

OBJECTIVE: To compare therapeutic outcomes after liver transplantation (LT) between hepatocellular carcinomas (HCC) with low and high risk for microvascular invasion (MVI) within the Milan criteria evaluated preoperatively. METHODS: Eighty patients with a single HCC who underwent LT as the initial therapy between 2008 and 2017 were included from two tertiary referral medical centers in a HBV-predominant population. A preoperative MVI-risk model was used to identify low- and high-risk patients. Recurrence-free survival (RFS) after LT between the two risk groups was compared using Kaplan-Meier curves with the log-rank test. Prognostic factors for RFS were identified using a multivariable Cox hazard regression analysis. RESULTS: Eighty patients were included (mean age, 51.8 years +/- 7.5 [standard deviation], 65 men). Patients were divided into low-risk (n = 64) and high-risk (n = 16) groups for MVI. The RFS rates after LT were significantly lower in the MVI high-risk group compared to the low-risk group at 1 year (75.0% [95% CI: 56.5-99.5%] vs. 96.9% [92.7-100%], p = 0.048), 3 years (62.5% [42.8-91.4%] vs. 95.3% [90.3-100%], p = 0.008), and 5 years (62.5% [42.8-91.4%] vs. and 95.3% [90.3-100%], p = 0.008). In addition, multivariable analysis showed that MVI high risk was the only significant factor for poor RFS (p = 0.016). CONCLUSION: HCC patients with a high risk of MVI showed significantly lower RFS after LT than those without. This model could aid in selecting optimal candidates in addition to the Milan criteria when considering upfront LT for patients with HCC if alternative treatment options are available. CLINICAL RELEVANCE STATEMENT: High risk for microvascular invasion (MVI) in hepatocellular carcinoma patients lowered recurrence-free survival after liver transplantation, despite meeting the Milan criteria. Identifying MVI risk could aid candidate selection for upfront liver transplantation, particularly if alternative treatments are available. KEY POINTS: • A predictive model-derived microvascular invasion (MVI) high- and low-risk groups had a significant difference in the incidence of MVI on pathology. • Recurrence-free survival after liver transplantation (LT) for single hepatocellular carcinoma (HCC) within the Milan criteria was significantly different between the MVI high- and low-risk groups. • The peak incidence of tumor recurrence was 20 months after liver transplantation, probably indicating that HCC with high risk for MVI had a high risk of early (≤ 2 years) tumor recurrence.

Factors associated with operational tolerance after liver transplantation: a single center retrospective study.

Background: Liver transplantation has adverse effects from life-long immunosuppression that limit the improvement of long-term outcomes. Achieving clinical operational tolerance is a major goal in organ transplantation. Methods: This study analyzed liver transplantation patients at a single institution from 1998 to 2020, excluding those who died within 1-year posttransplant. Operational tolerance was defined as normal liver function even after immunosuppressive drugs were discontinued. Propensity score matching was implemented at a 1:2 ratio for the tolerant group (TG) and the nontolerant group (NTG). Results: Out of 2,300 recipients, 99 achieved operational tolerance without rejection. No significant differences in sex or body mass index (BMI) were found between the TG and NTG. There was a significantly higher percentage of children in the TG (24.0%) than in the NTG (10.1%). The NTG had more living donor liver transplants. Among 2,054 adult recipients, no significant differences in age, sex, or BMI were found between the TG and the NTG. However, the rate of living donor liver transplantation was 40.3% (29/75) in the TG and 84.8% in the NTG (P<0.001). The propensity score-matched analysis showed higher chronic renal failure rates and a higher graft recipient weight ratio in the TG, along with shorter warm ischemic times during surgery. After immunosuppressant withdrawal, a significant increase in the ratio of CD4+CD25+ T cells to total CD4+ T cells was observed in the TG. Conclusions: These findings suggest that larger, healthier grafts are more conducive to inducing tolerance, and regulatory T cells are crucial in achieving tolerance.

Automated 3D liver segmentation from hepatobiliary phase MRI for enhanced preoperative planning.

Recent advancements in deep learning have facilitated significant progress in medical image analysis. However, there is lack of studies specifically addressing the needs of surgeons in terms of practicality and precision for surgical planning. Accurate understanding of anatomical structures, such as the liver and its intrahepatic structures, is crucial for preoperative planning from a surgeon's standpoint. This study proposes a deep learning model for automatic segmentation of liver parenchyma, vascular and biliary structures, and tumor mass in hepatobiliary phase liver MRI to improve preoperative planning and enhance patient outcomes. A total of 120 adult patients who underwent liver resection due to hepatic mass and had preoperative gadoxetic acid-enhanced MRI were included in the study. A 3D residual U-Net model was developed for automatic segmentation of liver parenchyma, tumor mass, hepatic vein (HV), portal vein (PV), and bile duct (BD). The model's performance was assessed using Dice similarity coefficient (DSC) by comparing the results with manually delineated structures. The model achieved high accuracy in segmenting liver parenchyma (DSC 0.92 ± 0.03), tumor mass (DSC 0.77 ± 0.21), hepatic vein (DSC 0.70 ± 0.05), portal vein (DSC 0.61 ± 0.03), and bile duct (DSC 0.58 ± 0.15). The study demonstrated the potential of the 3D residual U-Net model to provide a comprehensive understanding of liver anatomy and tumors for preoperative planning, potentially leading to improved surgical outcomes and increased patient safety.

Long-Term Outcomes of Liver Transplantation in Hepatocellular Carcinoma with Bile Duct Tumor Thrombus: A Comparison with Portal Vein Tumor Thrombus.

Liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) with bile duct tumor thrombus (BDTT) remains controversial. This study analyzed the recurrence and overall survival rates through long-term results after LT in HCC patients with BDTT and compared the results after LT in HCC patients with portal vein tumor thrombus (PVTT). We performed a retrospective study of 45 patients with PVTT, 16 patients with BDTT, and 11 patients with coexisting PVTT and BDTT among HCC patients who underwent LT at a single center from 1999 to 2020. The HCC recurrence rates were 40.4% at 1 year, 30.3.3% at 2 years, and 27.6% at 3 years in the PVTT group; 66.7%, 53.3%, and 46.7% in the BDTT group; and 22.2%, 22.2%, and 0% in the coexisting group (p = 0.183). Overall patient survival rates were 68.4% at 1 year, 54.3% at 2 years, and 41.7% at 3 years in the PVTT group; 81.3%, 62.5%, and 48.2% in the BDTT group; and 63.6%, 27.3%, and 0% in the coexisting group (p = 0.157). In the multivariate analysis, the pre-transplantation model for tumor recurrence after liver transplantation (MoRAL) score and model for end-stage liver disease (MELD) score were found to be independent risk factors for recurrence and survival in all groups. HCC patients with BDTT showed no difference in recurrence and survival compared with HCC patients with PVTT at the long-term follow-up after LT.

Graft-recipient-weight ratio and lowered immunosuppression is important for the success of adult liver retransplantation.

This study analyzed the risk of liver retransplantation and factors related to better outcome. Adult liver transplantations performed during 1996-2021 were included. Comparison between first transplantation and retransplantation were performed. Among retransplantation cases, comparison between whole liver and partial liver graft was performed. Multivariable Cox analyses for analyzing risk factors for primary graft and overall patient survival were performed for the entire cohort as well as the subgroup of patients with retransplantation. A total 2237 transplantations from 2135 adults were included and 103 cases were retransplantation. A total of 44 cases (42.7%) were related to acute graft dysfunction while 59 cases (57.3%) were related to subacute or chronic graft dysfunction. Retransplantation was related poor primary graft (HR 3.439, CI 2.230-5.304, P < 0.001) and overall patient survival. (HR 2.905, CI 2.089-4.040, P < 0.001) Among retransplantations, mean serum FK506 trough level ≥ 9 ng/mL was related to poor primary graft (HR 3.692, CI 1.288-10.587, P = 0.015) and overall patient survival. (HR 2.935, CI 1.195-7.211, P = 0.019) Graft-recipient-weight ratio under 1.0% was related to poor overall patient survival in retransplantations. (HR 3.668, CI 1.150-11.698, P = 0.028). Retransplantation can be complicated with poor graft and patient survival compared to first transplantation, especially when the graft size is relatively small. Lowering the FK506 trough level during the first month can be beneficial for outcome.

Donor Safety and Risk Factors of Pure Laparoscopic Living Donor Right Hepatectomy: A Korean Multicenter Study.

OBJECTIVE: The aim of this study was to identify safety and risk factors of living donor after pure laparoscopic donor right hepatectomy in a Korean multicenter cohort study. BACKGROUND: Pure laparoscopic donor right hepatectomy is not yet a standardized surgical procedure due to lack of data. METHODS: This retrospective study included 543 patients undergoing PLRDH between 2010 and 2018 in 5 Korean transplantation centers. Complication rates were assessed and multivariate logistic regression analyses were performed to identify risk factors of open conversion, overall complications, major complications, and biliary complications. RESULTS: Regarding open conversion, the incidence was 1.7% and the risk factor was body mass index >30 kg/m 2 [ P =0.001, odds ratio (OR)=22.72, 95% CI=3.56-146.39]. Rates of overall, major (Clavien-Dindo classification III-IV), and biliary complications were 9.2%, 4.4%, and 3.5%, respectively. For overall complications, risk factors were graft weight >700 g ( P =0.007, OR=2.66, 95% CI=1.31-5.41), estimated blood loss ( P <0.001, OR=4.84, 95% CI=2.50-9.38), and operation time >400 minutes ( P =0.01, OR=2.46, 95% CI=1.25-4.88). For major complications, risk factors were graft weight >700 g ( P =0.002, OR=4.01, 95% CI=1.67-9.62) and operation time >400 minutes ( P =0.003, OR=3.84, 95% CI=1.60-9.21). For biliary complications, risk factors were graft weight >700 g ( P =0.01, OR=4.34, 95% CI=1.40-13.45) and operation time >400 minutes ( P =0.01, OR=4.16, 95% CI=1.34-12.88). CONCLUSION: Careful donor selection for PLRDH considering body mass index, graft weight, estimated blood loss, and operation time combined with skilled procedure can improve donor safety.

Safety and Efficacy of Conversion to Once-Daily Tacrolimus from Twice-Daily Tacrolimus in Pediatric Liver Transplant Recipients.

BACKGROUND: Nonadherence to immunosuppression is the most common cause of late acute rejection in pediatric liver transplant (LT) recipients. A prolonged-release once-daily tacrolimus formulation was developed to improve adherence and long-term allograft survival. METHODS: We screened 179 pediatric LT recipients who converted from twice-daily tacrolimus (TD-TAC) to once-daily tacrolimus (OD-TAC) between February 2011 and September 2019. RESULTS: One hundred seventy-nine recipients converted to OD-TAC and were followed for 18 months. 152 OD-TAC-converted recipients (84.9%) experienced uneventful follow-up, while 21 recipients showed LFT elevation. Four recipients had biopsy-proven acute rejection within six months of conversion, all of which were successfully treated with steroid pulse. 166 recipients (92.7%) remain on OD-TAC and 13 (7.3%) were switched back to TD-TAC. The mean tacrolimus trough level significantly decreased three months following conversion (3.14 ± 1.9 ng/mL) compared with pre-conversion levels (3.69 ± 1.98 ng/mL). Mean tacrolimus trough levels remained unchanged from 3 months to 12 months following conversion. Percent coefficient of variation of tacrolimus trough levels decreased significantly from 32.5 ± 16.4 ng/mL to 27.5 ± 15.6 ng/mL after conversion to OD-TAC, reflecting a decrease in variation of tacrolimus trough levels following conversion. CONCLUSIONS: Conversion to OD-TAC in pediatric LT recipients with stable graft function is safe and effective. LEVEL OF EVIDENCE: Level IV.

Comparison of pure laparoscopic donor right posterior sectionectomy versus right hemihepatectomy for living donor liver transplantation.

The right posterior section (RPS) graft for living donor liver transplantation is an alternative graft in a live liver donor with insufficient remnant left lobe volume and portal vein anomaly. Although there have been some reports regarding pure laparoscopic donor right posterior sectionectomy (PLDRPS), no study has compared PLDRPS versus pure laparoscopic donor right hemihepatectomy (PLDRH). The aim of our study was to compare the surgical outcomes of PLDRPS versus PLDRH at centers achieving a complete transition from open to laparoscopic approach in liver donor surgery. From March 2019 to March 2022, a total of 351 living donor liver transplantations, including 16 and 335 donors who underwent PLDRPS and PLDRH, respectively, were included in the study. In the donor cohort, there were no significant differences in major complication (≥grade III) rate and comprehensive complication index between the PLDRPS versus PLDRH group (6.3% vs. 4.8%; p = 0.556 and 2.7 ± 8.6 vs.1.7 ± 6.4; p = 0.553). In the recipient cohort, there was a significant difference in major complication (≥grade III) rate (62.5% vs. 35.2%; p = 0.034) but no significant difference in comprehensive complication index (18.3 ± 14.9 vs. 15.2 ± 24.9; p = 0.623) between the PLDRPS and PLDRH groups. PLDRPS in live liver donors with portal vein anomaly and insufficient left lobe was technically feasible and safe with experienced surgeons. The PLDRPS group might be comparable with the PLDRH group based on the surgical outcomes of donors and recipients. However, in terms of recipient outcomes, more careful selection of donors of the RPS graft and further research in a large number of cases are necessary to evaluate the usefulness of PLDRPS.