Impact of live donor age (>or=50) on liver transplantation

Indications and results of right-lobe living donor liver transplantation

The shortage of deceased liver donor organs over the years has always posed the need to expand the donor pool. A viable alternative to deceased donors is that of the living donor. Indeed, the living donor in liver transplantation, initially in pediatric transplantation, but for several years now also in adult transplantation, is a more than viable alternative to deceased liver donation. In fact, right liver lobe donation has proven to be a surgical procedure with low impact on the donor's life in terms of morbidity and mortality, with excellent results in recipients of such organs. In recent years, an increasing number of studies have been published that show excellent results in right-lobe living donor liver transplantation, encouraging this practice not only in countries that have historically had a shortage of deceased donor organs, such as Asian countries, but making it a practice of increasing use in Western countries as well. In addition, thanks to improvements in surgical technique and the experience of high-volume centers, this surgery has also begun to be performed using minimally invasive surgical techniques, allowing us to envision ever better outcomes for both donor and recipient in the coming years.

Increasing practice and acceptable outcomes of high-MELD living donor liver transplantation in the USA

Recent deceased-donor allocation changes in the United States may have increased high-Model for End-Stage Liver Disease (MELD) living donor liver transplantation (LDLT); however, outcomes in these patients remain poorly defined. We aimed to examine the impact of the MELD score on LDLT outcomes. Using UNOS data (January 1, 2010-December 31, 2021), LDLT recipients were identified and stratified into low-MELD (<15), intermediate-MELD (15-24), and high-MELD (≥25) groups. We compared outcomes between MELD-stratified LDLT groups and between MELD-stratified LDLT and donation after brain death liver transplantation recipients. We used Kaplan-Meier analysis to compare graft survival rates and multivariable Cox proportional hazards modeling to identify factors associated with graft outcomes. Of 3558 LDLTs, 1605 (45.1%) were low-MELD, 1616 (45.4%) intermediate-MELD, and 337 (9.5%) high-MELD. Over the study period, the annual number of LDLTs increased from 282 to 569, and the proportion of high-MELD LDLTs increased from 3.9% to 7.7%. Graft survival was significantly higher in low-MELD versus high-MELD LDLT recipients (adjusted HR = 1.36, 95% CI: 1.03-1.79); however, 5-year survival exceeded 70.0% in both groups. We observed no significant difference in graft survival between high-MELD LDLT and high-MELD donation after brain death liver transplantation recipients (adjusted HR: 1.25, 95% CI:0.99-1.58), with a 5-year survival of 71.5% and 77.3%, respectively. Low LDLT center volume (<3 LDLTs/year) and recipient life support requirement were both associated with inferior graft outcomes among high-MELD LDLT recipients. While higher MELD scores confer graft failure risk in LDLT, high-MELD LDLT outcomes are acceptable with similar outcomes to MELD-stratified donation after brain death liver transplantation recipients. Future practice guidance should consider the expansion of LDLT recommendations to high-MELD recipients in centers with expertise to help reduce donor shortage.

Pure laparoscopic donor right hepatectomy in patients over 50 years old: Why age should not be a barrier

INTRODUCTION

Given the global aging population, the average age of liver donors is increasing. This study aimed to evaluate the surgical outcomes of grafts from pure laparoscopic donor right hepatectomy (PLDRH) in liver donors aged > 50 years.

METHODS

The medical records of liver donors were retrospectively reviewed. The donors underwent conventional donor right hepatectomy (CDRH) from January 2011 to May 2019 or PLDRH from March 2016 to May 2019. We divided the donors into three groups: PLDRH donors aged ≥50 (n = 26; Group 1) and aged < 50 (n = 257; Group 2), and CDRH donors aged ≥50 years (n = 66; Group 3).

RESULTS

Operation time (p < .01) and hospital stay (p < .01) were significantly lower in Group 1 than in Group 3. Other postoperative outcomes of donors including graft anatomical variation, graft weight, graft-to-recipient weight ratio, and hepatic steatosis were similar among the three groups. Although no postoperative complications occurred in Groups 1 and 3, they were detected in 17 cases (6.6%) in Group 2. No postoperative complications were detected among the recipients.

CONCLUSIONS

PLDRH was feasible and safe in donors aged over 50 years, with outcomes similar to those for donors aged <50 years. PLDRH should not be avoided solely based on the donor's age ≥50 years.

Impact of donor age on recipient morbidity and mortality after living donor liver transplantation

BACKGROUND

Evidence for use of graft from older donors in living donor liver transplantation (LDLT) has been conflicting. This study aims to clarify the impact of donor age on recipient morbidity and mortality after adult LDLT.

METHODS

A total of 90 live liver donors and recipients who underwent primary adult-to-adult LDLT were divided into three groups according to donor age: donors in 20s (D-20s) group, donors in 30s and 40s (D-30s and 40s) group and donors in 50s & 60s (D-50s and 60s) group. Multivariate analyses were conducted to look for independent risk/prognostic factors. Donor age was analysed as a continuous variable to determine an optimal cut off.

RESULTS

Overall donor morbidity was 4/90 (4.44%), major donor morbidity was 1/90 (1.11%) and there was no donor mortality. Recipients in the D-20s group had better 1-, 3- and 5-year recipient survival than recipients in the D-50s and 60s group (96%, 91%, 91% versus 73%, 58%, 58%, respectively) (P = 0.020). Donor age was identified to be an independently significant risk factor for increased major complications (P = 0.007) and prognostic factor for reduced overall survival (P = 0.014). The optimal donor age cut off was determined to be 46.5 years old.

CONCLUSION

Older donors are associated with poorer recipient outcomes after adult-to-adult LDLT. Usage of liver grafts from older donors should be carefully considered when choosing liver grafts for patients undergoing LDLT.

Impact of Donor and Recipient Age on Outcomes After Living Donor Liver Transplant

BACKGROUND

Living donor liver transplant between elderly donors and recipients has gained popularity, but the effects of their age remain unknown. Our aim is to evaluate the effects of matching by donor and recipient age with special insights into their recovery periods.

METHODS

Ninety-five living donor liver transplant pairs, excluding the left lateral segment graft cases, who underwent surgery were enrolled. Median follow-up was 97 months (range, 1-212 months). Elderly recipients were classified as being 51 years or older. Donor-recipient pairs were divided into (1) nonelderly donor/nonelderly recipient (YY) (n = 26), (2) elderly donor/nonelderly recipient (n = 8), (3) nonelderly donor/elderly recipient (n = 38), and (4) elderly donor/elderly recipient (EE) (n = 23).

RESULTS

The 1-, 3-, and 5-year survival rates were 92.7%, 92.7%, and 88.9% (YY); 75.0%, 62.5%, and 62.5% (EY); 80.5%, 76.3%, and 67.9% (EY); and 86.9%, 82.6%, and 78.1% (EE) (P = .30), respectively. Perioperative parameters were comparable between the 4 groups. Liver grafts from the elderly population exhibited higher peaks of transaminases post-transplant regardless of recipient age (P ≤ .05). Postoperative recovery of total bilirubin in the EE group was relatively slower (P = .27). Required rates of plasma exchange postoperatively were relatively higher in the EE group (34.8% vs 15.4% in the YY group).

CONCLUSIONS

These findings suggest a modest and not statistically significant effect that elderly liver grafts exhibit slower recovery trajectories in the acute phase but finally achieve acceptable outcomes.

Impact of Donor Age on the Outcome of Living-donor Liver Transplantation: Special Consideration to the Feasibility of Using Elderly Donors

BACKGROUND

The use of elderly donors (≥60 y) in living-donor liver transplantation (LDLT) remains controversial. In this study, we aimed to determine the safety of surgery for elderly donors and the impact of donor age on LDLT outcomes.

METHODS

We, retrospectively, reviewed 470 cases of LDLT at Kumamoto University Hospital from December 1998 to March 2017.

RESULTS

Donors were divided into 5 groups according to age: 20-29 (n = 109), 30-39 (n = 157), 40-49 (n = 87), 50-59 (n = 81), and ≥60 (n = 36). At our institution, elderly donor candidates required additional preoperative work-up. There were no significant differences in the incidence of postoperative complications and duration of postoperative hospital stay among the 5 donor groups. Regardless of graft type, elderly donors were comparable to younger donor groups (<30 y) in postoperative recovery of liver function. Risk-adjusted overall survival rates of recipients among donor groups were not significantly different. Additionally, donor age was not significantly associated with 6-month graft survival of adult and pediatric recipients.

CONCLUSIONS

Elderly candidates ≥60 years of age can safely be selected as LDLT donors after meticulous preoperative work-up.

Liver donor age affects hepatocyte function through age-dependent changes in decellularized liver matrix

The only treatment available for end stage liver diseases is orthotopic liver transplantation. Although there is a big donor scarcity, many donor livers are discarded as they do not qualify for transplantation. Alternatively, decellularization of discarded livers can potentially render them transplantable upon recellularization and functional testing. The success of this approach will heavily depend on the quality of decellularized scaffolds which might show variability due to factors including age. Here we assessed the age-dependent differences in liver extracellular matrix (ECM) using rat and human livers. We show that the liver matrix has higher collagen and glycosaminoglycan content and a lower growth factor content with age. Importantly, these changes lead to deterioration in primary hepatocyte function potentially due to ECM stiffening and integrin-dependent signal transduction. Overall, we show that ECM changes with age and these changes significantly affect cell function thus donor age should be considered as an important factor for bioengineering liver substitutes.

Expanding Indications for Liver Transplant: Tumor and Patient Factors

During the past few decades, liver transplant has developed from a high-mortality procedure to an almost routine procedure with good survival outcomes. The development of living donor liver transplant has increased the availability of liver grafts, and the scope of indications for liver transplant has been expanding ever since. The aim of this review is to provide an overview of such an expansion of scope. Various criteria have been proposed to expand the eligibility of patients with hepatocellular carcinoma exceeding the Milan criteria for liver transplant. Furthermore, liver transplant is increasingly performed as a treatment modality for cholangiocarcinoma, neuroendocrine liver metastasis and colorectal liver metastasis. The number of elderly patients receiving liver transplant is on the rise. Combined organ transplantation has also been adopted to treat patients with multiple organ failure. Going forward, further development of preoperative noninvasive predictors in tumor, patient and even donor factors is needed to identify patients at risk of poor outcomes and hence optimize patient management.

Clinical Outcome of Residual Liver Volume and Hepatic Steatosis After Right-Lobe Living-Donor Hepatectomy

Background

We examine how residual liver volume (RLV) and hepatic steatosis (HS) of living liver donors affect the regeneration process and clinical outcomes.

Material/Methods

We longitudinally studied 58 donors who underwent right-lobe hepatectomy during the period February 2014 to February 2015 at a single medical institution. The patients were classified based on RLV (30–35%, 35–40%, 40–50%) subgroups and HS (<10%, 10–30%, 30–50%) subgroups. Clinical parameters such as clinical outcome, liver volumetric recovery (LVR,%) rate and remnant left-liver (RLL,%) growth rate were collected for analysis.

Results

The clinical features of postoperative peak total bilirubin (p=.024) were significant in the 3 RLV subgroups. Body mass index (p=.017), preoperative alanine transaminase (p<.001), and pleural effusion (p=.038) were significant in the 3 HS subgroups. The LVR rate and RLL growth rate equations showed significant variation in regeneration among the 3 RLV subgroups. The LVR rate and RLL growth rate equations did not show significant variation in regeneration among the 3 HS subgroups.

Conclusions

Hyperbilirubinemia was a risk factor in the small-RLV group, and a large amount of pleural effusion was a risk factor in the steatosis 30–50% group. Hepatic steatosis subgroups did not show significantly different degrees of regeneration. The safety of living donors was a major concern while we compiled the extended living-donor criteria presented in this paper.

Impact of Donor Age on Recipient Survival in Adult-to-Adult Living-donor Liver Transplantation

OBJECTIVE

To investigate the influence of donor age on recipient outcome after living-donor partial liver transplantation (LDLT).

BACKGROUND

Donor age is a well-known prognostic factor in deceased donor liver transplantation; however, its role in LDLT remains unclear.

METHODS

We retrospectively analyzed 315 consecutive cases of primary adult-to-adult LDLT in our center between April 2006 and March 2014. Recipients were divided into 5 groups according to the donor age: D-20s (n = 60); D-30s (n = 72); D-40s (n = 57); D-50s (n = 94); and D-60s (n = 32). The recipient survival and the association with various clinical factors were investigated.

RESULTS

Recipient survival proportions were significantly higher in D-20s compared with all the other groups (P = 0.008, < 0.001, < 0.001, and = 0.006, vs D-30s, -40s, -50s, and -60s, respectively), whereas there was no association between recipient survival and their own age. There are 3 typical relationships between donors and recipients in adult-to-adult LDLT: from child-to-parent, between spouses/siblings, and from parent-to-child. The overall survival in child-to-parent was significantly higher than in spouses/siblings (P = 0.002) and in parent-to-child (P = 0.005), despite significantly higher recipient age in child-to-parent [59 (42-69) years, P < 0.001]. Contrastingly, parent-to-child exhibited the lowest survival, despite the youngest recipient age [26 (20-43) years, P < 0.001]. In addition, younger donor age exhibited significantly better recipient survival both in hepatitis C virus-related and in non-hepatitis C virus diseases. Univariate and multivariate analyses both demonstrated that donor age and graft-type (right-sided livers) are independent prognostic factors for recipient survival.

CONCLUSIONS

Donor age is an independent, strong prognostic factor in adult-to-adult LDLT.

Impact of donor age on liver regeneration and function following adult living donor liver transplantation

The aim of the present study was to evaluate the impact of donor age on liver function and regeneration following living donor liver transplantation. Donors were divided into an elderly donor group (age >50 years old; n=8) and a young donor group (age <30 years old; n=35). The recipients were also divided into an elderly group (age >50 years old; n=5) and a young group (age <30 years old; n=25). Alanine aminotransferase, aspartate aminotransferase, total bilirubin (TB) and prothrombin time were recorded 1-5 days postoperatively. The liver regeneration ratio (LRR) was recorded 7 and 15 days postoperatively in donors and at 0.5, 1, 3 and 6 months postoperatively in recipients by contrast-enhanced multi-slice spiral computed tomography. Notably, the LRR in the young donor group was significantly increased compared with that in the elderly donor group at 7 days postoperatively (P<0.05). Among recipients, TB in the elderly group was significantly increased compared with that in the young group at 1-5 days postoperatively (P<0.05). The residual liver regeneration rate was decreased and the time of jaundice was prolonged in recipients in the elderly group 7 days postoperatively, but donor age had little impact on the short-term outcome of the residual liver and graft.

Feasibility of using marginal liver grafts in living donor liver transplantation

Liver transplantation (LT) is one of the most effective treatments for end-stage liver disease caused by related risk factors when liver resection is contraindicated. Additionally, despite the decrease in the prevalence of hepatitis B virus (HBV) over the past two decades, the absolute number of HBsAg-positive people has increased, leading to an increase in HBV-related liver cirrhosis and hepatocellular carcinoma. Consequently, a large demand exists for LT. While the wait time for patients on the donor list is, to some degree, shorter due to the development of living donor liver transplantation (LDLT), there is still a shortage of liver grafts. Furthermore, recipients often suffer from emergent conditions, such as liver dysfunction or even hepatic encephalopathy, which can lead to a limited choice in grafts. To expand the pool of available liver grafts, one option is the use of organs that were previously considered “unusable” by many, which are often labeled “marginal” organs. Many previous studies have reported on the possibilities of using marginal grafts in orthotopic LT; however, there is still a lack of discussion on this topic, especially regarding the feasibility of using marginal grafts in LDLT. Therefore, the present review aimed to summarize the feasibility of using marginal liver grafts for LDLT and discuss the possibility of expanding the application of these grafts.

Living Donor Liver Transplantation: Technical Innovations

Living donor liver transplantation (LDLT) has found a place to serve the end-stage liver disease community as the donor safety and recipient suitability has been elucidated. Donor safety is of paramount importance and transplant programs must continue endeavors to maintain the highest possible standards. At the same time, adequacy of grafts based on recipient clinical status via their model for end-stage liver disease (MELD) score and volumetric studies to achieve a GRBWR >0.8, along with special attention to anatomic tailoring and portal venous flow optimization are necessary for successful transplantation. Technical innovations have improved sequentially the utility and availability of LDLT.

A Donor Age-Based and Graft Volume-Based Analysis for Living Donor Liver Transplantation in Elderly Recipients

Background

Given the expected increase in the number of elderly recipients, details regarding how clinical factors influence the outcome in living donor liver transplantation (LDLT) for the elderly remain unclear. We examined the survival outcomes according to the results of donor age-based and graft volume–based analyses and assessed the impact of prognostic factors on the survival after LDLT for elderly recipients.

Methods

The 198 adult recipients were classified into 2 groups: an elderly group (n = 70, E group; ≥ 60 years of age) and a younger group (n = 128, Y group; <60 years of age). We analyzed the prognostic factors for the survival in the E group and the survival rate for both groups at several follow-up points and conducted subgroup analyses in the E group by combining the donor age (≥50 vs <50 years) and graft weight (GW)/standard liver volume (SLV) (≥40% vs <40%).

Results

Donor age (hazard ratio [HR], 2.17; P = 0.062) and GW/SLV (HR, 1.80; P = 0.23) tended to have a high HR in the E group. The overall patient survival rates at 1, 3, and 5 years were 78.3%, 73.0%, and 61.0% in the E group, and 82.0%, 75.1%, and 69.2% in the Y group, respectively (P = 0.459). However, the outcomes tended to be worse in recipients of grafts from donors ≥50 years of age than in those with grafts from younger donors with GW/SLV < 40% (P = 0.048).

Conclusions

A worse outcome might be associated with aging of the donor, which leads to impairment of the graft function and liver regeneration. Both the graft volume and donor age should be considered when choosing grafts for LDLT in elderly patients.

Mechanism of impairment on liver regeneration in elderly patients: Role of hepatic stellate cell function

Japan, along with most other countries in the world, is facing an increasingly aging population with a prolonged life expectancy. Concurrently, the need for medical intervention, including hepatectomy, has also increased for the elderly. Although surgical outcomes for older patients are reported to be comparable with those for younger patients, additional care in the selection of older patients for hepatectomy is considered necessary. Although the effect of aging on human liver regeneration is not fully understood, the regeneration of liver tissue after hepatectomy in elderly patients is shown to be generally worse than in younger patients and, to date, the mechanisms involved in the impairment of liver regeneration have not been fully clarified. Hepatic stellate cells (HSCs) are liver-specific mesenchymal cells that play critical roles in liver physiology and fibrogenesis. Recent studies in liver regeneration have increasingly focused on HSCs rather than on hepatocytes, Kupffer cells, endothelial cells, or infiltrating immune cells and suggest that HSCs might play a critical role in liver regeneration. In this review, we summarize the mechanisms involved in the impairment of liver regeneration in elderly patients, especially focusing on HSCs. We also discuss how HSCs contribute to the impairment of liver regeneration.

Small-for-size syndrome in live donor liver transplantation-Pathways of injury and therapeutic strategies

Due to the severe organ shortage and the increasing gap between the supply and demand for donor grafts, live donor liver transplantation (LDLT) has become an accepted and alternative technique for the expansion of the donor pool. However, donor safety and good recipient outcomes must be balanced regarding risk stratification and decision-making within this patient population. Small-for-size syndrome (SFSS) is one of the complications encountered after LDLT, thus increasing the burden of optimizing donor graft selection and effective treatments during its occurrence. A graft-to-recipient weight ratio (GRWR) <0.8 predisposes the graft to SFSS. However, other factors may induce this complication even without a graft-to-patient size mismatch. Several strategies to prevent this complication include portal vein flow and liver outflow modulation, as well as pharmacological treatment. Also, as an entity with a multifactorial etiology, outcomes vary between right-lobe, left-lobe, and posterior-lobe donation among series encountered in the literature. In this review, we analyze the pathophysiology and classification of this complication, the state-of-the-art on management of SFSS, and the outcomes regarding the best treatment strategy on this patient population.

Live Donor Liver Transplantation With Older (≥50 Years) Versus Younger (<50 Years) Donors: Does Age Matter?

OBJECTIVE

To compare the outcome of adult live donor liver transplantation (LDLT) with grafts from older versus younger donors.

INTRODUCTION

Using older donor grafts for adult LDLT may help expand the donor pool. However, the risks of LDLT with older donors remain controversial, and many centers are reluctant to use live donors aged 45 years or older for adult LDLT.

METHODS

Outcomes of patients receiving a LDLT graft from donors aged 50 years or older (n = 91) were compared with those receiving a live donor graft from donors younger than 50 years (n = 378).

RESULTS

Incidences of biliary (LDLT <50: 24% vs LDLT ≥50: 23%; P = 0.89) and major complications (LDLT <50: 24% vs LDLT ≥50: 24%; P = 1) were similar between both groups of recipients. No difference was observed in 30-day recipient mortality (LDLT <50: 3% vs LDLT ≥50: 0%; P = 0.13). The 1- (90% vs 90%), 5- (82% vs 73%), and 10- (71% vs 58%) year graft survival was statistically similar between both groups (P = 0.075). Likewise, patient survival after 1- (92% vs 96%), 5- (83% vs 79%), and 10- (76% vs 69%) years was also similar (P = 0.686). Overall, donors rate of major complications (Dindo-Clavien ≥3b) within 30 days was low (n = 2.3%) and not different in older versus younger donors (P = 1). Donor median hospital stay in both groups was identical [LDLT <50: 6 (4-17) vs LDLT ≥50: 6 (4-14) days; P = 0.65]. No donor death occurred and all donors had full recovery and returned to baseline activity.

CONCLUSIONS

Right lobe LDLT with donors aged 50 years or older results in acceptable recipient outcome without increased donor morbidity or mortality. Potential live donors should not be declined on the basis of age alone.

A review of current status of living donor liver transplantation

Living donor liver transplantation (LDLT) has become an inevitable procedure in Asia due to its shortage of deceased donor under the influence of the religion and native cultures. Through a broad variety of experience, LDLT has been evolved and extended its indication. Although there have been many surgical and ethical efforts to prevent donor risk, concerns of donor's safety still are remaining questions due to its strict selection criteria. Therefore, dual grafts LDLT or ABO incompatible (ABO-I) LDLT may be effective means in its application and safety aspect. Many Asian LDLT centers have pointed out the useful extended criteria of LDLT for hepatocellular carcinoma (HCC), but the applicability of extended criteria should be validated and standardized by worldwide prospective studies based on the Milan criteria. Recent struggling efforts have been reported to surmount extensive portal vein thrombosis and Budd-Chiari syndrome which were previously contraindicated to LDLT. There is no doubt that LDLT is a surely complicated therapy to be performed successfully and requires devoted efforts by surgeons and co-workers. Nonetheless, comprehensive increasing understandings of partial graft LT and improvements of surgical techniques with challenges to obstacles in LDLT will make its prosperity with satisfactory outcomes.

Impact of elderly donors for liver transplantation: A single-center experience

Elderly donor grafts for liver transplantation (LT) are recognized to be marginal grafts. The present study investigated the impact of using elderly donors for LT. Between June 1990 and August 2012, 1631 patients received LT at Kyoto University Hospital. Out of 1631 patients, 1597 patients received living donor liver transplantation (LDLT), whereas the other 34 patients underwent deceased donor liver transplantation (DDLT). Seventy-five grafts that were used came from individuals who were ≥60 years old. We retrospectively analyzed the recipients' survival rates according to donor age. The overall survival rates of the recipients of all LDLT (P < 0.001), adult-to-adult LDLT (P = 0.007), all DDLT (P = 0.026), and adult-to-adult DDLT (P = 0.011) were significantly lower for the elderly donor group versus the younger group and especially for those who were hepatitis C-positive. A multivariate analysis revealed that donor age, ABO incompatibility, and preoperative intensive care unit stay were independent risk factors for poor patient survival in adult-to-adult LDLT. However, no significant differences existed between the 2 groups among those who received adult-to-adult LDLT in and after April 2006. No significant association was found between donor age and incidence of acute cellular rejection. In conclusion, donor age was closely related to the survival rate for LDLT and DDLT, although the impact of donor age was not shown in the recent cases.

The Influence of Aging on Hepatic Regeneration and Early Outcome after Portal Vein Occlusion: A Case-Control Study

BACKGROUND

Portal vein occlusion (PVO) is used to increase inadequate future liver remnant volume (FLRV). Impaired liver regeneration has been reported in aged animals. This study was designed to evaluate the impact of patient age on hepatic regeneration.

METHODS

Sixty patients aged ≥70 years were matched 1:1 with 60 patients aged <70 years. Matching criteria were sex, diabetes, cirrhosis, pre-PVO chemotherapy and bevacizumab administration, and jaundice.

RESULTS

The median ages in the older and younger groups were 76 (range 70-83) years and 59 (range 20-69) years, respectively (p < 0.001). Median FLRV following PVO (33.1 ± 6.8 vs. 31.9 ± 6.0 %) and volumetric increase (0.52 ± 0.35 vs. 0.49 ± 0.34) were similar in the two groups. Of the older and younger patients, 10 % and 1.7 %, respectively, did not undergo liver surgery after PVO (p = 0.051). Mortality (5.5 vs. 6.7 %) and major morbidity (25.9.8 vs. 22 %) rates were similar. Liver failure rate was higher in older patients (35.1 vs. 16.9 %, p < 0.026), mainly due to Grade A liver failure (20.3 vs. 8.4 %, p < 0.001). Multivariate analysis showed that age ≥ 70 years [odds ratio (OR) 3.03; 95 % confidence interval (CI) 1.18-7.78; p = 0.020] and biliary cancer diagnosis (OR 4.69; 95 % CI 1.81-12.09; p = 0.001) were independent risk factors for postoperative liver failure.

CONCLUSIONS

Liver regeneration after PVO is not impaired by age. Nevertheless, liver resection in elderly patients is performed less often after PVO and carries a higher risk of liver failure.

A complete treatment of adult living donor liver transplantation: a review of surgical technique and current challenges to expand indication of patients

The growing disparity between the number of liver transplant candidates and the supply of deceased donor organs has motivated the development of living donor liver transplantation (LDLT). Over the last two decades, the operation has been markedly improved by innovations rendering modern results comparable with those of deceased donor liver transplantation (DDLT). However, there remains room for further innovation, particularly in adult living donor liver transplantation (ALDLT). Unlike whole-size DDLT and pediatric LDLT, size-mismatching between ALDLT graft and recipient body weight and changing dynamics of posttransplant allograft regeneration have remained major challenges. A better understanding of the complex surgical anatomy and physiologic differences of ALDLT helps avoid small-for-size graft syndrome, graft congestion from outflow obstruction and graft hypoperfusion from portal flow steal. ALDLT for high-urgency patients (Model for End-Stage Liver Disease score >30) can achieve results comparable to DDLT in high volume centers. Size limitations of partial grafts and donor safety issues can be overcome with dual grafts and modified right-lobe grafts that preserve the donor's middle hepatic vein trunk. Extended application of LDLT for unresectable hepatocellular carcinoma above Milan criteria is an optional strategy at the cost of slightly compromised survival. ABO-blood group incompatibility obstacles have been broken down by introducing a paired donor exchange program and refined peri-operative management of ABO-incompatible ALDLT. This review focuses on recent innovations of surgical techniques, safe donor selection, current strategies to expand ALDLT with broadened patient selection criteria and important aspects of teamwork required for success.

Importance of donor-recipient age gradient to the prediction of graft outcome after living donor liver transplantation

PURPOSE

Advanced donor age is a well-known risk factor for poor graft function after living donor liver transplantation (LDLT). In addition, advanced recipient age has a significant impact because of the high prevalence of comorbidities. We investigated the relationship between donor-recipient age gradient (DRAG) and the posttransplant outcomes in LDLT.

METHODS

We included 821 consecutive adult recipients who underwent LDLT from June 1997 to May 2011. According to the value of DRAG, they were divided into 2 groups: Negative years (the donor was younger than the recipient) and positive years (the donor was older than the recipient). These groups were further divided into subgroups (≤-21, -20 to -1, 0 to 20, and ≥21 years). We collected retrospectively patient characteristics, laboratory results, medical and surgical complications, and graft loss.

RESULTS

The positive DRAG group had higher level of posttransplant alkaline phosphatase, but a lower incidence of biliary complications. The negative DRAG group, particularly DRAG ≤ -21 years was associated with the superior 1-, 3-, 5-, and 10-year graft survivals. Recipients with DRAG ≥ 21 showed persistently inferior graft survival during the observation period. In cases of young donors, transplants utilizing lower DRAG seen between young donors and older recipients showed more favorable graft survival than that of young-to-young transplants.

CONCLUSION

This study demonstrated that DRAG and a fixed donor age limit could be significant factors to predict graft survival after LDLT. Patients should carefully consider the worse graft survival if the donor is older than the recipient by ≥20.

Outcome of patients undergoing right lobe living donor liver transplantation with small-for-size grafts

AIM: To investigate the outcome of living donor liver transplantation (LDLT) recipients transplanted with small-for-size grafts (SFSGs).

METHODS: Between November 2001 and December 2010, 196 patients underwent LDLT with right lobe liver grafts at our center. Recipients were divided into 2 treatment groups: group A with an actuarial graft-to-recipient weight ratio (aGRWR) < 0.8% (n = 45) and group B with an aGRWR ≥ 0.8% (n = 151). We evaluated serum liver function markers within 4 wk after transplantation. We also retrospectively evaluated the outcomes of these patients for potential effects related to the recipients, the donors and the transplantation procedures based upon a review of their medical records.

RESULTS: Small-for-size syndrome (SFSS) developed in 7 of 45 patients (15.56%) in group A and 9 of 151 patients (5.96%) in group B (P = 0.080). The levels of alanine aminotransferase and aspartate aminotransferase in group A were higher than those in group B during early period after transplantation, albeit not significantly. The cumulative 1-, 3- and 5-year liver graft survival rates were 82.22%, 71.11% and 71.11% for group A and 81.46%, 76.82%, and 75.50% for group B patients, respectively (P = 0.623). However, univariate analysis of risk factors associated with graft survival in group A demonstrated that the occurrence of SFSS after LDLT was the only significant risk factor affecting graft survival (P < 0.001). Furthermore, multivariate analysis of our data did not identify any additional significant risk factors accounting for poor graft survival.

CONCLUSION: Our study suggests that LDLT recipients with an aGRWR < 0.8% may have liver graft outcomes comparable to those who received larger size grafts. Further studies are required to ascertain the safety of using SFSGs.

Donor age affects liver regeneration during early period in the graft liver and late period in the remnant liver after living donor liver transplantation

BACKGROUND

The aim of the present study was to evaluate the influence of donor age on liver regeneration and surgical outcomes in recipients and donors.

PATIENTS AND METHODS

Among 101 cases of adult-to-adult living donor liver transplantation (LDLT) between March 2002 and March 2011, according to donor age: younger (Y) <50 years of age or older (O) ≥ 50 years of age, the donors and recipients using right (R) or left (L) graft were divided into groups Y/R (n = 51) and O/R (n = 17), and groups Y/L (n = 26) and O/L (n = 7), respectively. Remnant liver volume (RemLV) and graft liver volume (GLV) were estimated by computed tomography (CT) volumetry. A disintegrin and metalloprotease with thrombospondin type I domain 13 (ADAMTS13) activities and von Willebrand factor (vWF) antigen levels were measured as factors reflecting thrombotic microangiopathy.

RESULTS

Among the donors, RemLV/total liver volume (TLV) was lower in group O/R than in group Y/R, although there were no significant differences by t-test with the Bonferroni correction (rough p value = 0.02 at 6 months and rough p value > 0.05 at 1, 3, and 12 months). Donor age (≥ 50 years) was independently correlated with impaired remnant liver regeneration at 6 months in right lobe LDLT (p = 0.04). Among the recipients, GLV/standard liver volume (SLV) was lower during the first month, although there were no significant differences between the two groups by t-test with the Bonferroni correction (rough p value = 0.03 at 1 week and rough p value >0.05 at 2 weeks and 1 and 3 months). Donor age (≥ 50 years) was independently correlated with impaired graft liver regeneration at 1 week in both right and left lobe LDLT (p < 0.05). ADAMTS13 activities were lower in group O/R than in group Y/R, although there were no significant differences by t-test with the Bonferroni correction (rough p value = 0.049 on postoperative days (POD) 1 and 28 and rough p value >0.05 on POD 7 and 14). vWF/ADAMTW13 ratios were higher on POD 14, although there were no significant differences between the two groups by t-test with the Bonferroni correction (rough p value = 0.044 on POD 14 and rough p value >0.05 on POD 1, 7, 14, and 28).

CONCLUSIONS

The surgical outcomes using older donor livers for LDLT were comparable to those using younger donor livers. When using older donor livers, however, we should pay attention to the liver volume for recipients as well as donors, because older donor livers might have impaired regenerative ability.

The influence of donor age on liver regeneration and hepatic progenitor cell populations

BACKGROUND

Recent reports suggest that donor age might have a major impact on recipient outcome in adult living donor liver transplantation (LDLT), but the reasons underlying this effect remain unclear. The aims of this study were to compare liver regeneration between young and aged living donors and to evaluate the number of Thy-1+ cells, which have been reported to be human hepatic progenitor cells.

METHODS

LDLT donors were divided into 2 groups (Group O, donor age ≥ 50 years, n = 6 and Group Y, donor age ≤ 30 years, n = 9). The remnant liver regeneration rates were calculated on the basis of computed tomography volumetry on postoperative days 7 and 30. Liver tissue samples were obtained from donors undergoing routine liver biopsy or patients undergoing partial hepatectomy for metastatic liver tumors. Thy-1+ cells were isolated and counted using immunomagnetic activated cell sorting (MACS) technique.

RESULTS

Donor liver regeneration rates were significantly higher in young donors compared to old donors (P = .042) on postoperative day 7. Regeneration rates were significantly higher after right lobe resection compared to rates after left lobe resection. The MACS findings showed that the number of Thy-1+ cells in the human liver consistently tended to decline with age.

CONCLUSION

Our study revealed that liver regeneration is impaired with age after donor hepatectomy, especially after right lobe resection. The declining hepatic progenitor cell population might be one of the reasons for impaired liver regeneration in aged donors.

Utilization of elderly donors in living donor liver transplantation: when more is less?

An accepted definition of donor exclusion criteria has not been established for living donor liver transplantation (LDLT). The use of elderly donors to expand the living donor pool raises ethical concerns about donor safety. The aims of this study were (1) the comparison of the postoperative outcomes of living liver donors by age (≥ 50 versus < 50 years) and (2) the evaluation of the impact of the extent of right hepatectomy on donor outcomes. The study group included 150 donors who underwent donor right hepatectomy between October 2004 and April 2009. Extended criteria surgery (ECS) was defined as right hepatectomy with middle hepatic vein (MHV) harvesting or right hepatectomy resulting in an estimated remnant liver volume (RLV) less than 35%. The primary endpoints were donor outcomes in terms of donor complications graded according to the Clavien classification. Group 1 consisted of donors who were 50 years old or older (n = 28), and group 2 consisted of donors who were less than 50 years old (n = 122). At least 1 ECS criterion was present in 74% of donors: 57% had 1 criterion, and 17% had 2 criteria. None of the donors had grade 4 complications or died. The overall and major complication rates were similar in the 2 donor age groups [28.6% and 14.3% in group 1 and 32% and 8.2% in group 2 for the overall complication rates (P = 0.8) and the major complication rates (P = 0.2), respectively]. However, there was a significant correlation between the rate of major complications and the type of surgery in donors who were 50 years old or older. In LDLT, extending the limits of surgery comes at the price of more complications in elderly donors. Right hepatectomy with MHV harvesting and any procedure causing an RLV less than 35% should be avoided in living liver donors who are 50 years old or older.

Liver transplantation using University of Wisconsin or Celsior preserving solutions in the portal vein and Euro-Collins in the aorta

INTRODUCTION

Orthotopic liver transplantation (OLT) is today the gold standard treatment of the end-stage liver disease. Different solutions are used for graft preservation. Our objective was to compare the results of cadaveric donor OLT, preserved with the University of Wisconsin (UW) or Celsior solutions in the portal vein and Euro-Collins in the aorta.

METHODS

We evaluated retrospectively 72 OLT recipients, including 36 with UW solution (group UW) and 36 with Celsior (group CS). Donors were perfused in situ with 1000 mL UW or Celsior in the portal vein of and 3000 mL of Euro-Collins in the aortia and on the back table managed with 500 mL UW or Celsior in the portal vein, 250 mL in the hepatic artery, and 250 mL in the biliary duct. We evaluated the following variables: donor characteristics, recipient features, intraoperative details, reperfusion injury, and steatosis via a biopsy after reperfusion. We noted grafts with primary nonfunction (PNF), initial poor function (IPF), rejection episodes, biliary duct complications, hepatic artery complications, re-OLT, and recipient death in the first year after OLT.

RESULTS

The average age was 33.6 years in the UW group versus 41 years in the CS group (P = .048). There was a longer duration of surgery in the UW group (P = .001). The other recipient characteristics, ischemia-reperfusion injury, steatosis, PNF, IPF, rejection, re-OLT, and recipient survival were not different. Stenosis of the biliary duct occured in 3 (8.3%) cases in the UW group and 8 (22.2%) in the CS (P = .19) with hepatic artery thrombosis in 4 (11.1%) CS versus none in the UW group (P = .11).

CONCLUSION

Cadaveric donor OLT showed similar results with organs preserved with UW or Celsior in the portal vein and Euro-Collins in the aorta.

Gender-specific differences associated with living donor liver transplantation: a review study

Living donor liver transplantation (LDLT) has developed into an important therapeutic option for liver diseases. For living donor kidney transplantation (LDKT), gender-specific differences have been observed among both donors (two-thirds being women and one-third being men) and recipients (two-thirds being men and one-third being women). The aim of this study was to determine whether there is a gender disparity for LDLT. We contacted 89 national and international transplantation registries, single transplant centers, and coordinators. In addition, a sample of 274 articles dealing with LDLT and its outcomes was reviewed and compared with the registry data. The data included the gender of the donors and recipients, the country of transplantation, and the donor-recipient relationship. The investigation showed that overall there were slightly more men among the donors (53% male and 47% female). As for the recipients, 59% of the organs were distributed to males, and 41% were distributed to females. Differences in the gender distribution were observed with respect to individual countries. Worldwide, 80% of the donors were blood-related, 11% were not blood-related, and 9% were spouses. The data acquired from the publications were similar to the registry data. Our research has shown that there are hardly any registry data published, a lot of countries do not have national registries, or the access to these data is difficult. Even widely ranging published studies often do not give information on the gender distribution or the donor-recipient relationship. Further investigations are needed to understand the possible medical, psychosocial, or cultural reasons for gender distribution in LDLT and the differences in comparison with LDKT.

In-hospital mortality in adult recipients of living donor liver transplantation: experience of 576 consecutive cases at a single center

Adult living donor liver transplantation (LDLT) was developed against the background of a scarcity of deceased donors and has a number of disadvantages leading to in-hospital mortality, such as marginal donors and grafts and recipients suffering from severe conditions. We have thus developed surgical and medical innovations to overcome these disadvantages. The present study analyzes the causes of death and factors affecting in-hospital mortality in adult recipients of LDLT. Between November 1994 and December 2007, 576 consecutive adult patients underwent LDLT at a single medical center. Overall in-hospital mortality was 18.9%. The peak rate was 55.6% in 1996, and the rate gradually decreased thereafter to 4.4% in 2007. The most frequent cause of death was infection (62.5%), which was followed by rejection (15.7%) and nonseptic multiple-organ failure (8.9%). Being intensive care unit-bound before the operation, ABO blood type incompatibility, an absence of postoperative enteral nutrition, and a Model for End-Stage Liver Disease score of 25 or higher were independent risk factors for in-hospital mortality. In ABO-identical and ABO-compatible cases, retransplantation and a positive lymphocyte crossmatch test were additional independent risk factors. In conclusion, even aggressive efforts, preoperative conditions such as being intensive care unit-bound, a high Model for End-Stage Liver Disease score, retransplantation, and a positive lymphocyte crossmatch test are still risk factors. Enteral nutrition could be a promising strategy to improve adult LDLT.