Graft-recipient Weight Ratio Research Articles

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

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. 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). 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. These findings suggest that larger, healthier grafts are more conducive to inducing tolerance, and regulatory T cells are crucial in achieving tolerance.

Unusual grafts for living-donor liver transplantation

PurposeUnusual grafts, including extended left liver plus caudate lobe, right anterior section, and right posterior section grafts, are alternatives to left and right lobe grafts for living-donor liver transplantation. This study aimed to investigate unusual grafts from the perspectives of recipients and donors.MethodsFrom 2016 to 2021, 497 patients received living-donor liver transplantation at Severance Hospital. Among them, 10 patients received unusual grafts. Three patients received extended left liver plus caudate lobe grafts, two patients received right anterior section grafts, and five patients received right posterior section grafts. Liver volumetrics and anatomy were analyzed for all recipients and donors. We collected data on laboratory examinations (alanine aminotransferase, total bilirubin, international normalized ratio), imaging studies, graft survival, and complications. A 1:2 ratio propensity-score matching method was used to reduce selection bias and balance variables between the unusual and conventional graft groups.ResultsThe median of Model for End-stage Liver Disease score of unusual graft recipients was 13.5 (interquartile range 11.5–19.3) and that of graft–recipient weight ratio was 0.767 (0.7–0.9). ABO incompatibility was observed in four cases. The alanine aminotransferase level, total bilirubin level, and international normalized ratio decreased in both recipients and donors. Unusual and conventional grafts had similar survival rates (p = 0.492). The right and left subgroups did not differ from each counter-conventional subgroup (p = 0.339 and p = 0.695, respectively). The incidence of major complications was not significantly different between unusual and conventional graft recipients (p = 0.513). Wound seromas were reported by unusual graft donors; the complication ratio was similar to that in conventional graft donors (p = 0.169).ConclusionAlthough unusual grafts require a complex indication, they may show feasible surgical outcomes for recipients with an acceptable donor complication.

Feasible living donor liver transplantation for patients on chronic hemodialysis: a multicenter study in East Asian countries.

End-stage liver and kidney disease is an indication for simultaneous liver and kidney transplantation. However, in countries where deceased donor transplantation is not well established, living donor liver transplantation (LDLT) is a realistic option for patients on hemodialysis (HD). We investigated the outcomes of LDLT for patients on HD. We conducted a retrospective multicenter survey of patients on chronic HD who underwent LDLT in East Asian countries. The characteristics of donors and recipients and the short and long-term outcomes were analyzed. Between 2001 and 2021, 45 patients on HD underwent LDLT and 11 of these patients also underwent kidney transplantation (KT). The overall survival rate at 5years of the 34 patients who underwent only LDLT was 44.5%. Multivariate analysis identified a low graft recipient weight ratio (< 1%) (p = 0.048) and long HD duration (≥ 10years) (p = 0.046) as independent predictors of poor overall survival. The major complication was posttransplant bleeding, which occurred in12 patients (35%). It is important to establish the indications for LDLT, taking into consideration graft size and HD duration in candidate patients on HD.

Analysis of Outcome in Recipients with Different Graft-Recipient-Weight-Ratio (GRWR) Post Adult to Adult Living Donor Liver Transplant (LDLTx)

Abstract Background The problem of graft size is one of the critical factors limiting the expansion of adultto-adult living donor liver transplantation (LDLT). Graft-to-recipient weight ratio (GRWR) &amp;gt; 0.8% is perceived as the critical graft size to meet the metabolic demand of the recipient. Small-for-size graft (SFSG) is the graft with GRWR &amp;lt; 0.8 and when its unable to meet the recipients metabolic demands, small-for-size syndrome (SFSS) occurs which is a life-threatening condition with rapidly progressive liver failure. This lower limit of GRWR (0.8%) has been challenged over the last decade perhaps due to better understanding of the pathophysiology, coupled with technical refinements, particularly related to venous outflow reconstruction. Aim of Work Our aim was to analyse the different outcomes of patients undergoing Living donor liver transplantation using grafts with GRWR ≤ 0.8% with those &amp;gt;0.8% to evaluate the factors that affect the post-operative outcome and the overall one year Graft survival. Methods This is a retrospective cohort study on 100 adult patients with ESLD or HCC (mean age 54.16 ± 10.53 years old) who underwent adult LDLT in the period between 2018 and 2020 and follow up the patients for one year post transplant, Patients were divided into two groups, patients who received Graft with GRWR ≤ 0.8 (N = 22 patients with lower limit of GRWR = 0.58 and there is 7 patients with GRWR ≤ 0.7) and those with GRWR &amp;gt;0.8 (N = 78 patients). We compared the the Donor factors, preoperative patient factors, intraoperative factors, development of small for size syndrome and graft survival in patients received small-for-size grafts (GRWR ≤ 0.8) with patients received GRWR &amp;lt;0.8. Results We retrospectively evaluated the donor factors, recipient factors and operative factors through the medical records. Small-for-size syndrome (SFSS) occurred in 2 of 22 patients (9.1%) in patients with GRWR ≤ 0.8 and in 1 of 78 patients (1.3%) in patients with GRWR &amp;gt;0.8 which was statistically insignificant between two groups. There was No significant difference in the Donor age, Preoperative MELD, CHILD, Portal hypertension, cold and warm ischemia, operative time, presence of PVT and HCC in patients who received GRWR ≤ 0.8 and patients with GRWR &amp;gt;0.8. the mean overall survival for all the studied cases was found 43.35 months and the overall survival at 6 months and 1 year was 96.0% but there was statistically significant increase in the overall survival of cases with GRWR &amp;gt;0.8 than those with GRWR ≤ 0.8 with p-value = 0.009, as the overall 6 months and 1 year survival for patients with GRWR &amp;gt;0.8 was 98% and 98 % compared to 86 % and 86 % in thoses with GRWR ≤ 0.8 Conclusion There is no difference in the outcome in form of development of Small for size syndrome when we use Grafts with GRWR &amp;gt;0.8 or with GRWR ≤ 0.8, However the venous Outflow of SFSG (GRWR &amp;lt; 0.8) is very critical to maintain good graft function in the recipient.

Reduced-Size Left Lateral Segment Grafts in Infants Weighing

Live donor liver transplantation for infants weighing <10 kg has unique complexities, as patient/graft size discrepancies may cause vascular perfusion deficiencies. Failure of the abdominal closure further complicates this already challenging procedure. To overcome these potential problems, several techniques for graft size reduction-either anatomic or nonanatomic-have been proposed in the literature. Technically easier and less time-consuming, nonanatomic size reductions have the advantage of avoiding the risk of injury to the portal pedicle. This study aimed to evaluate and compare the effects of nonanatomic graft size reduction in infants weighing <10 kg with a large estimated preoperative graft recipient weight ratio. We enrolled 106 infants weighing <10 kg. Of these infants, 50 received reduced-size grafts. The outcomes were compared between the groups. No difference was observed between the groups according to survival and vascular or biliary complications. None of the patients required an open abdomen or mesh closure. Nonanatomic size reduction of left lateral segment grafts can be safely applied without compromising vascular supply, graft function, and patient survival with comparable vascular and biliary complication rates. This technique is safe and efficient in overcoming the complications caused by large-for-size syndrome in infants weighing <10 kg.

Liver Only Living Donor Transplantation for Polycystic Disease in a Patient on Chronic Hemodialysis: Case Report

Polycystic liver disease (PLD) is characterized by the progressive development of polycystic lesions in the kidney and the liver, possibly resulting in dual organ failure. We indicated living donor liver transplantation (LDLT) for a patient with end-stage liver and kidney disease (ELKD) due to PLD on uncomplicated chronic hemodialysis. A 63-year-old man with ELKD and uncontrolled massive ascites due to PLD and hepatitis B on uncomplicated chronic hemodialysis was referred to us with a single possible 47-year-old female living donor. Because of the necessity of right lobe liver procurement from this small middle-aged donor and uncomplicated hemodialysis on this recipient, we considered LDLT, rather than dual organ transplantation, could be the most well-balanced option to save the life of this recipient with acceptable risk limits for this donor. A right lobe graft with 0.91 for graft recipient weight ratio was implanted with an uneventful operative procedure under intra- and postoperative continuous hemodiafiltration. The recipient was rescheduled on routine hemodialysis on day 6 after transplantation and recovered with a gradual decrease in ascites output. He was discharged on day 56. He continues to have a very good liver function and quality of life without ascites and uncomplicated routine hemodialysis 1 year after transplantation. The living donor was discharged 3 weeks after surgery and is also doing well. Although combined liver-kidney transplantation from a deceased donor could be the best option for ELKD due to PLD, LDLT can also be an acceptable option for ELKD with uncomplicated hemodialysis, considering the double equipoise theory for both lifesaving of the recipient and acceptable donor risk.

The Impact of the Multiple Bile Ducts on Postoperative Biliary Complications In Patients Undergoing Living Donor Liver Transplantation

We aimed to investigate the correlation between bile duct number and biliary complications in patients who underwent donor liver transplantation (LDLT). We reviewed all patients who underwent LDLT in our hospital between July 2008 and December 2020. The patients were divided into 2 groups according to the number of bile ducts in the living donor graft (single duct [SD] or multiple ducts [MD]). Collected data included donor and recipient demographics, surgical data including bile duct reconstruction, and perioperative and postoperative outcomes. No prisoners were used in this study, and participants were neither coerced nor paid. The current study complies with the Helsinki Congress and the Declaration of Istanbul. All 70 patients were classified as SD (n=48) and MD (n=22). Complications related to the bile duct occurred in 27 (38.6%) patients and were more common in the MD group (54.5% vs 31.3%; odds ratio, 2.4). The MD patients had a longer operation time (1052 ± 251 vs 910 ± 215 minutes, P=.019) and a higher percentage of hepaticojejunostomy (31.8% vs 8.3%, P=.012). Donor age, graft-recipient weight ratio, cold ischemic time, and transfusion volume did not differ between groups. Twenty-one patients (77.7%) fully recovered from complications related to the bile duct, but 3 patients (4.3%) had liver graft failure. Bile duct-related complications were common in LDLT patients, despite overall good results. Multiple bile ducts may be a potent risk factor for postoperative biliary complications.

P9.12: The Impact of the Multiple Bile Ducts on Postoperative Biliary Complications in Living Donor Liver Transplantation: Single Center Experience

Introduction: The multiple bile ducts in a living donor graft are a long standing troublesome. All transplant surgeons try to avoid this problem due to technical difficulty and relation with biliary complications. However, there have been many mixed reviews about the impact of multiple bile ducts on biliary complications. This study aimed to investigate correlations between the number of bile duct and biliary complications in patients undergoing living donor liver transplantation (LDLT). Methods: We reviewed all LDLT patients in our hospital between July 2008 and December 2020. The patients were divided into 2 groups according to the number of bile duct in living donor graft (single duct=SD, multiple duct=MD). Biliary complications were defined by endoscopic, interventional or surgical treatment. Collected data included demographics of donors and recipients, surgical data about to biliary anastomosis (duct-to-duct, hepaticojejunostomy, and conjoined), perioperative and postoperative outcomes. Results: All 70 patients were represented SD (n=48) and MD (n=22). Biliary complications occurred in 27(38.6%) patient and were more common in MD group (54.5% vs 31.3%). Although there were no statistic differences between 2 groups, multiple bile ducts was positively correlated with biliary complications (HR=2.4). MD patients revealed longer operation time (1052 ± 251 vs 910 ± 215 p=0.019) and higher percentage of hepaticojejunostomy (31.8% vs 8.3%, p=0.012). Donor age, graft-recipient weight ratio, cold ischemic time and amount of transfusion were not different between 2 groups. Twenty-one (77.7%) were fully recovered from biliary complications but 3(4.3%) resulted in graft failure. Conclusion: Biliary complications were common problems in LDLT despite overall good result. Multiple bile ducts can be a potent risk factor of biliary complications among other predisposing factors.

Alternatives to left lateral sector in paediatric liver transplantation-a systematic review on monosegmental and reduced grafts.

BackgroundPaediatric liver transplantation (pLT) is the treatment of choice for many liver conditions. However, it still poses relevant challenges, mainly related to the size of the recipients. Unlike in adults, excessive graft volume might represent an issue when the estimated graft-recipient-weight-ratio (GRWR) is significantly disproportionate. In this situation, the traditional left lateral sector (LLS) grafts are too big and other alternatives are required, such as monosegmental or reduced (including hyper-reduced) grafts (RLLS/HRLLS). Results with conventional LLS-pLT are excellent and replicating them with monosegmental or RLLS is challenging given (I) the technical complexity and (II) the need to overcome the large-for-size scenario. This article is to review the existing experience with monosegmental, RLLS/HRLLS grafts and appraise its results.MethodsSystematic search of the electronic databases, conducted from their inception until May 2020.ResultsAfter scrutiny of the available literature, 16 studies were included reporting 330 patients transplanted with monosegmental and RLLS/HRLLS grafts. There were 10 re-grafts (6 of them <90 days); 90% of grafts were LDLT. Overall, median recipient’s age and weight were 7 months (range, 5 days–22 months) and 5.8 kg (range, 2.6–8 kg) respectively. Median graft weight was 209 grams (range, 124–264 grams) and median GRWR was 3.5% (range, 2.7–5.6%). Hepatic artery and portal vein thrombosis overall incidence were 1.5% and 4.2%; 120 out of the 330 pLT were monosegmental (37%) producing a smaller graft (median of 164 grams) and accordingly a lower GRWR (median 3.2%) compared to reduced LLS. With a median follow-up of 39 months (range, 6–87 months), the overall graft and patient survival were 84% (285/340) and 89% (295/330).DiscussionMonosegmental and RLLS/HRLLS grafts provide access to liver transplantation for very small recipients with excellent results comparable to the standard LLS.

Therapeutic Plasma Exchange for Management of Early Allograft Dysfunction After Living Donor Liver Transplant: An Unmatched Cohort Study.

Therapeutic plasma exchange has been reported to be useful in the management of acute liver failure and acute-on-chronic liver failure. This retrospective study evaluated therapeutic plasma exchange as an adjunct to standard supportive care for early allograft dysfunction after living donor liver transplant. All consecutive adult living donor liver transplants performed from January 2015 to February 2019 were included. Patients treated without or with therapeutic plasma exchange for early allograft dysfunction (Olthoff criteria) were compared. There were 465 adult transplant recipients, and 67 (14.4%) had early allograft dysfunction, of which 43 (64%) had therapeutic plasma exchange and 24 (36%) did not. Fourteen patients were excluded, as they had both preoperative and immediate postoperative therapeutic plasma exchange (5 patients with acute liver failure and 9 with acute-on-chronic liver failure). The therapeutic plasma exchange group (n = 29) had more preoperative acute kidney injury (55.2% vs 25.0%; P = .009), lower graft-recipient weight ratio (0.96 vs 1.09; P = .043), and slightly higher final portal pressure (11 vs 10 mg/dL; P = .027). Therapeutic plasma exchange was started at a median of postoperative day 9, with median serum bilirubin of 13.6 mg/dL and a median of 3 sessions per patient. There was no 90-day mortality in the group without therapeutic plasma exchange; however, in the therapeutic plasma exchange group, 13 patients (45%) died (P < .001). Patients who received therapeutic plasma exchange had more septic complications (62.1% vs 12.5%; P < .001) and needed more postoperative renal replacement therapy (51.7% vs 8.3%; P < .001). This is the first study to compare patients treated with or without therapeutic plasma exchange for early allograft dysfunction in the living donor liver transplant setting. Within the limitations of this retrospective study, we were unable to confirm whether therapeutic plasma exchange could increase early mortality.

Impact of Graft Size Matching on the Early Post-Transplant Complications and Patients Survival in Children after Living Donor Liver Transplantations.

We aimed to assess the impact of the graft-recipient weight ratio (GRWR) on early post-transplant complications and patient survival rates in children after living donor liver transplantation (LDLT). We retrospectively analyzed 321 patients who underwent LDLT from 2004 to 2019. The recipients were categorized into four groups: 37 patients had a GRWR ≤ 1.5% (Group A), 196 patients had a GRWR > 1.5% and ≤3.5% (Group B), 73 patients had a GRWR > 3.5% and <5% (Group C) and 15 patients had a GRWR ≥ 5% (Group D). Incidence of early surgical complications including vascular complications, biliary complications, postoperative bleedings, gastrointestinal perforations and graft loss were comparable among groups with a different GRWR. Delayed abdominal wound closure was more common in patients with a GRWR > 3.5%. Recipients with a GRWR < 5% had a significantly better prognosis concerning patients and graft survival. Using grafts with a GRWR < 5% allows us to expand the donor pool and decrease the risk of mortality while on the waiting list, when patients at the time of transplantation have less advanced liver disease. LDLT with a GRWR ≥ 5% is related to a higher risk of poor outcome, and thus should be an option for treating selected patients when the risk of a delayed transplantation is high and access to deceased donors is limited.

Pure laparoscopic living donor hepatectomy for the right posterior segment graft

The right posterior segment (RPS) graft was introduced as an alternative to expand donor pool. The first LDLT case using an RPS graft was reported in 2001, the RPS graft has not been widely used in LDLT because of lack of donors with suitable anatomical variation, technical challenge for safe donor hepatectomy and surgical difficulties in recipient operation. We present the 3 cases of pure laparoscopic donor hepatectomy with RPS graft. For donor evaluation, we performed laboratory test, abdominal ultrasonography and dynamic computed tomography (CT) scan. Graft selection was determined based on volumetric analysis. In 3 cases of RPS graft, the ratio of the remnant liver volume/whole liver volume was less than 0.3 and left lobe graft was small for metabolic demand of recipients. All 3 donors had type 3 portal vein variation. The Graft Recipient Weight Ratio (GRWR) was 0.72, 0.81, and 1.34 in each case. Preoperative magnetic resonance cholangiopancreatography (MRCP) was performed to evaluate bile duct anomaly. In 3 cases, we had no open conversion, intraoperative and postoperative transfusion. Cut surface bile leakage occurred in one case, but bile leakage decreased without procedure or intervention, the donor discharged at postoperative day 9. He had no more complications. Recipients were recovered uneventfully and discharged. To meet the donor's safety and recipient's metabolic demand, graft selection is one of the important factors in LDLT, the RPS graft is an alternative to expand donor pool. However, thorough preoperative evaluation to understand the anatomical variation is necessary even for experienced transplant surgeons.

Dextroplantation of a reduced left lateral section graft in an infant undergoing living donor liver transplantation

Graft size matching is essential for successful liver transplantation in infant recipients. We present our technique of graft dextroplantation used in an infant who underwent living donor liver transplantation (LDLT) using a reduced left lateral section (LLS) graft. The patient was an 11-month-old 7.8 kg-weighing female infant with hepatoblastoma. She was partially responsive to systemic chemotherapy, thus LDLT was performed to treat the tumor. The living donor was a 34-year-old mother of the patient. After non-anatomical size reduction, the weight of the reduced LLS graft was 235 g, which was 3.0% of the graft-recipient weight ratio. Recipient hepatectomy was performed according to the standard procedures of pediatric LDLT. At the beginning of graft implantation, the graft was temporarily placed at the abdomen to determine the implantation location. The graft portal vein was anastomosed with an interposed external iliac vein homograft. As the liver graft was not too large and it was partially accommodated in the right subphrenic fossa, the abdominal wall wound was primarily closed. The patient recovered uneventfully. An imaging study revealed deep accommodation of the graft within the right subphrenic fossa. The patient has been doing well for 3 months without any vascular complications. Dextroplantation of a reduced LLS graft can be a useful technical option for LDLT in infant patients.

Prognosis of hepatic epithelioid hemangioendothelioma after living donor liver transplantation

Epithelioid hemangioendothelioma (EHE) is a rare borderline vascular tumor. Due to its rarity and protean behavior, the optimal treatment of hepatic EHE has not yet been standardized. This single-center study describes outcomes in patients with hepatic EHE who underwent living donor liver transplantation (LDLT). The medical records of patients who underwent LDLT for hepatic EHE from 2007 to 2016 were reviewed. During 10-year period, four patients, one man and three women, of mean age 41.3 ± 11.1 years, underwent LDLT for hepatic EHE. Based on imaging modalities, these patients were preoperatively diagnosed with EHE or hepatocellular carcinoma, with percutaneous liver biopsy confirming that all four had hepatic EHE. The tumors were multiple and scattered over entire liver, precluding liver resection. Blood tumor markers were not elevated, except that CA19-9 and des-γ-carboxy prothrombin was slightly elevated in one patient. Mean model for end-stage liver disease score was 10.8 ± 5.7. All patients underwent LDLT using modified right liver grafts, with graft-recipient weight ratio of 1.11 ± 0.19, and all recovered uneventfully after LDLT. One patient died due to tumor recurrence at 9 months, whereas the other three have done well without tumor recurrence, resulting in 5-year disease-free and overall patient survival rates of 75% each. The patient with tumor recurrence was classified as a high-risk patient based on the original and modified hepatic EHE-LT scoring systems. LDLT can be an effective treatment for patients with unresectable hepatic EHEs that are confined within the liver and absence of macrovascular invasion and lymph node metastasis.

3D-reconstruction and heterotopic implantation of reduced size monosegment or left lateral segment grafts in small infants: A new technique in pediatric living donor liver transplantation to overcome large-for-size syndrome

BackgroundMonosegmental grafts and reduced left lateral segment grafts have been introduced to overcome the problems of large-for-size grafts in pediatric living donor liver transplantation. Here, we introduce a new method of reduced size monosegment or left lateral segment grafts transplanted in the right diaphragmatic fossa heterotopically in small infants. MethodsThere were 4 infants who underwent living donor liver transplantation with heterotopically implanted reduced monosegmental or left lateral segment grafts at our center. The demographic, operative, postoperative, and follow-up data of these infants were collected from our prospectively designed database and reviewed. Technical details of the donor and recipient operation are shared and a supplemental provided. ResultsThe mean recipient age was 7.5 ± 0.9 months (range: 5–10 months), and body weight was 5.9 ± 0.7 kg (range: 4.6–7.8). Primary diagnoses of the recipients were biliary atresia (n:3) and progressive familial intrahepatic cholestasis (n:1). Mean graft-recipient weight ratio was 3.3 ± 0.2. Reduced monosegment III grafts were used in 2 cases, and reduced left lateral segment grafts were used in the other 2 patients. Bile duct reconstruction was done by Roux-en-Y hepaticojejunostomy in 3 patients and duct-to-duct anastomosis in the remaining patient. All patients recovered from the liver transplantation operation and are doing well at a mean follow-up of 8 months. ConclusionLiving donor liver transplantation with heterotopically implanted reduced monosegmental or left lateral segment seems feasible for the treatment of neonates and extremely small infants. Further accumulation of cases and long-term follow-up are necessary to collect data for the establishment of this treatment modality.

"Graft Recipient Weight Ratio" or "Graft Volume Standard Liver Volume Ratio" in clinical practice in living donor liver transplantation.

We enjoyed the recently published article by Toshima et al,1 demonstrating the importance of recipient BMI for choosing graft in living donor liver transplantation (LDLT) to prevent small-for-size graft syndrome (SFSS). They retrospectively analyzed the incidence of SFSS in 694 recipients who underwent LDLT according to required graft volume based on graft-to-recipient body weight ratio (GRWR) or graft weight to standard liver weight (GW/SLW) in strata of recipient body mass index (BMI). They concluded that GRWR was useful, but GW/SLW was not useful in obese recipients (BMI > 30 kg/m2). Small-for-size graft syndrome has high mortality and morbidity after LDLT because of early graft dysfunction. The importance of accurate estimation for required liver volume in LDLT has been growing with increased number of LDLT worldwide due to the shortage of donor organs. GW/SLW was proposed in 1995 by calculating standard liver volume using the formula, which includes body surface area.2 However, the formula might have less generalizability because they calculated standard liver volume in 96 patients in one prefecture in Japan. In addition, the average of height and body weight were 164.8 cm and 56.5 kg, respectively. Therefore, it may be difficult to estimate standard liver volume and graft weight in obese donors and recipients. In fact, Toshima et al showed GW/SLW was not associated with SFSS in obese patients. GRWR has been another way to estimate required liver volume. Since GRWR could take the body weight of a recipient into account, it may give us a better estimation in obese patients. The estimation of graft weight has been performed using volumetric analysis by three-dimensional computed tomography (CT). However, the discrepancy between estimated graft volume and actual graft weight are often observed, and can potentially cause SFSS. A study showed that estimated liver volume was the largest using the venous phase of enhanced CT, while the smallest using unenhanced CT.3 In addition, estimated liver volume by volumetry is provided as “volume” (i.e. mL), while actual graft size is measured by “weight” (i.e. g). To address this difference, another study suggested using conversion factor (1.20 mL/g) in estimation of graft weight.4 Furthermore, the actual graft weight measured on the back table could decrease from preoperatively estimated liver volume due to several factors including dehydration caused by University of Wisconsin solution, and the difference between the virtual and actual resection line of the liver. The coefficient factor of 0.85 in non-cirrhotic liver for graft weight estimation from preoperative CT volumetry has been proposed to address these factors.5 Although Toshima et al described the utility of GRWR in obese patients, they used actual procured graft weight for the analysis. Since graft weight could not be changed once it has been taken out from the donor, it is important to predict actual graft weight more accurately in the setting of preoperative volumetric analysis. We believe that this article by Toshima et al would provide a compelling rationale for further investigations into comprehensive ways to estimate liver volume more accurately, potentially avoiding SFSS and improving donor shortage. Conflict of Interest: The authors declare no conflicts of interest. Author Contribution: Study concept and design: Koichiro Haruki and Toru Ikegami. Drafting of the manuscript: Koichiro Haruki and Kenei Furukawa. Critical revision of the manuscript for important intellectual content: all authors. Study supervision: Toru Ikegami. Final approval of manuscript: all authors.

Pediatric split liver transplantation for congenital factor X deficiency: first 10-year follow-up of a case with portal vein stenting

Congenital factor X (FX) deficiency is a rare autosomal-recessive disease that induces bleeding disorder. Herein, we present the 10-year posttransplant course of a pediatric patient who underwent liver transplantation (LT) with portal vein (PV) stenting for correction of severe congenital FX deficiency, with focus on long-term maintenance of coagulation function and patency of PV stenting. A 17-month-old infant with recurrent hemorrhagic episodes due to FX deficiency underwent split LT using a left lateral section graft. The graft-recipient weight ratio was 2.2%. The graft implantation procedures were performed by following the standard pediatric split LT procedure. Nevertheless, a wall stent was inserted due to PV anastomotic stenosis on posttransplant day 1. Graft function recovered slowly because of partial parenchyma infarct, and the patient was discharged at 46 days after LT operation. The FX activity started to increase soon after LT and gradually normalized; the coagulation profiles have been maintained well for the past 10 years. The patient has been doing well for the past 10 years after LT without any episodes of abnormal bleeding. Due to the risk of vascular complications owed to PV stenting, life-long follow-up is mandatory with special attention until attainment of complete physical growth to adolescent and adulthood.

Prognosis of hepatic epithelioid hemangioendothelioma after living donor liver transplantation.

BackgroundEpithelioid hemangioendothelioma (EHE) is a rare borderline vascular tumor. Due to its rarity and protean behavior, the optimal treatment of hepatic EHE has not yet been standardized. This single-center study describes outcomes in patients with hepatic EHE who underwent living donor liver transplantation (LDLT).MethodsThe medical records of patients who underwent LDLT for hepatic EHE from 2007 to 2016 were reviewed.ResultsDuring 10-year period, four patients, one man and three women, of mean age 41.3±11.1 years, underwent LDLT for hepatic EHE. Based on imaging modalities, these patients were preoperatively diagnosed with EHE or hepatocellular carcinoma, with percutaneous liver biopsy confirming that all four had hepatic EHE. The tumors were multiple and scattered over entire liver, precluding liver resection. Blood tumor markers were not elevated, except that CA19-9 and des-γ-carboxy prothrombin was slightly elevated in one patient. Mean model for end-stage liver disease score was 10.8±5.7. All patients underwent LDLT using modified right liver grafts, with graft-recipient weight ratio of 1.11±0.19, and all recovered uneventfully after LDLT. One patient died due to tumor recurrence at 9 months, whereas the other three have done well without tumor recurrence, resulting in 5-year disease-free and overall patient survival rates of 75% each. The patient with tumor recurrence was classified as a high-risk patient based on the original and modified hepatic EHE-LT scoring systems.ConclusionsLDLT can be an effective treatment for patients with unresectable hepatic EHEs that are confined within the liver and absence of macrovascular invasion and lymph node metastasis.

Fates of retained hepatic segment IV and its prognostic impact in adult split liver transplantation using an extended right liver graft.

PurposeWhen splitting a liver for adult and pediatric graft recipients, the retained left medial section (S4) will undergo ischemic necrosis and the right trisection graft becomes an extended right liver (ERL) graft. We investigated the fates of the retained S4 and its prognostic impact in adult split liver transplantation (SLT) using an ERL graft.MethodsThis was a retrospective analysis of 25 adult SLT recipients who received split ERL grafts.ResultsThe mean model for end-stage liver disease (MELD) score was 27.3 ± 10.9 and graft-recipient weight ratio (GRWR) was 1.98 ± 0.44. The mean donor age was 26.5 ± 7.7 years. The split ERL graft weight was 1,181.5 ± 252.8 g, which resulted in a mean GRWR of 1.98 ± 0.44. Computed tomography of the retained S4 parenchyma revealed small ischemic necrosis in 16 patients (64.0%) and large ischemic necrosis in the remaining 9 patients (36.0%). No S4-associated biliary complications were developed. The mean GRWR was 1.87 ± 0.43 in the 9 patients with large ischemic necrosis and 2.10 ± 0.44 in the 15 cases with small ischemic necrosis (P = 0.283). The retained S4 parenchyma showed gradual atrophy on follow-up imaging studies. The amount of S4 ischemic necrosis was not associated with graft (P = 0.592) or patient (P = 0.243) survival. A MELD score of >30 and pretransplant ventilator support were associated with inferior outcomes.ConclusionThe amount of S4 ischemic necrosis is not a prognostic factor in adult SLT recipients, probably due to a sufficiently large GRWR.

Prognosis of hepatic epithelioid hemangioendothelioma after living donor liver transplantation

Background: Epithelioid hemangioendothelioma (EHE) is a rare borderline vascular tu mor. Due to its rarity and protean behavior, the optimal treatment of hepatic EHE has not yet been standardized. This single-center study describes outcomes in patients with he patic EHE who underwent living donor liver transplantation (LDLT). Methods: The medical records of patients who underwent LDLT for hepatic EHE from 2007 to 2016 were reviewed. Results: During 10-year period, four patients, one man and three women, of mean age 41.3±11.1 years, underwent LDLT for hepatic EHE. Based on imaging modalities, these pa tients were preoperatively diagnosed with EHE or hepatocellular carcinoma, with percu taneous liver biopsy confirming that all four had hepatic EHE. The tumors were multiple and scattered over entire liver, precluding liver resection. Blood tumor markers were not elevated, except that CA19-9 and des-γ-carboxy prothrombin was slightly elevated in one patient. Mean model for end-stage liver disease score was 10.8±5.7. All patients under went LDLT using modified right liver grafts, with graft-recipient weight ratio of 1.11±0.19, and all recovered uneventfully after LDLT. One patient died due to tumor recurrence at 9 months, whereas the other three have done well without tumor recurrence, resulting in 5-year disease-free and overall patient survival rates of 75% each. The patient with tumor recurrence was classified as a high-risk patient based on the original and modified he patic EHE-LT scoring systems. Conclusions: LDLT can be an effective treatment for patients with unresectable hepat ic EHEs that are confined within the liver and absence of macrovascular invasion and lymph node metastasis.