Older liver graft transplantation, cholestasis and synthetic graft function

Nodular Regenerative Hyperplasia Is Not a Rare Condition After Liver Transplantation: Incidence, Predictive Factors, and Impact on Survival

BACKGROUND

The objectives of this study were to evaluate incidence and to identify the risk factors of occurrence and the predictive factors of symptomatic forms of nodular regenerative hyperplasia (NRH) after liver transplantation (LT).

METHODS

To identify risk factors of NRH following LT, we included 1648 patients transplanted from 2004 to 2018 and compared the patients developing NRH after LT to those who did not. To identify predictive factors of symptomatic NRH, we selected 115 biopsies displaying NRH and compared symptomatic to asymptomatic forms. Symptomatic NRH was defined as the presence of ascites, esophageal varices, hepatic encephalopathy, portal thrombosis, retransplantation, or death related to NRH.

RESULTS

The incidence of NRH following LT was 5.1%. In multivariate analysis, the independent factor of developing NRH after LT was the donor's age (odds ratio [OR] = 1.02; confidence interval, 1.01-1.03; P = 0.02). Symptomatic forms occurred in 29 (25.2%) patients: 19 (16.5%) patients presented with ascites, 13 (11.3%) with esophageal varices, 4 (3.5%) with hepatic encephalopathy, and 8 (7%) with portal thrombosis. The median period before the onset of symptoms was 8.4 (1.5-11.3) y after LT. The spleen size at diagnosis/before LT ratio (OR = 12.5; 114.17-1.37; P = 0.0252) and thrombectomy during transplantation (OR = 11.17; 1.48-84.11; P = 0.0192) were associated with symptomatic NRH in multivariate analysis.

CONCLUSIONS

NRH following LT is frequent (5.1%) and leads to symptomatic portal hypertension in 25.2% of patients. Using older grafts increases the risk of developing NRH after LT. Clinicians should screen for signs of portal hypertension, particularly in measuring spleen size.

Liver transplantation for non-resectable colorectal liver metastasis: where we are and where we are going

PURPOSE

Almost 50% of patients diagnosed with colorectal cancer (CRC) will develop liver metastasis (LM). Although their only long-term curative treatment is surgery, less than half of these patients can be eventually resected. Therefore, palliative chemotherapy is offered as a definitive option, though with poor results. Recently, the University of Oslo group has published encouraging results in the treatment of these patients with liver transplantation (LT), whereby worldwide interest in this option has been renewed.

METHODS

A literature review of LT for patients with unresectable colorectal metastasis was performed. This included information regarding patient selection, complications, overall survival (OS) and disease-free survival (DFS), immunosuppression, chemotherapy, and description of the ongoing trials.

RESULTS

Improvements in OS and DFS have been observed in consecutive published prospective trials, as patient selection has been refined. Papers reporting OS of patients who randomly presented similar selection criteria also exhibited good results.

CONCLUSION

LT within the available therapeutic options in patients with CRC-LM seems to be a compelling alternative in carefully selected patients. The ongoing trials will provide valuable information regarding selection criteria, immunosuppressive therapy and different modalities of adjuvant chemotherapy, which are, to our knowledge, the vital platform of LT in CRC-LM. Although some of the developing techniques involve living donors, graft availability for these patients remains a matter of major concern.

Liver transplantation for colorectal liver metastasis

PURPOSE OF REVIEW

The aim of this review is to discuss existing data on liver transplantation for colorectal liver metastasis, emerging controversies, and future directions.

RECENT FINDINGS

Contemporary experience with transplanting patients with liver metastasis from colon cancer is mainly derived from European centers, with a large proportion being from a single institution (SECA study), made possible in part by a relatively high donor pool. The initial results prove to be encouraging by demonstrating an overall survival advantage over unresectable patients with liver-limited disease managed with chemotherapy only. Recurrence patterns, however, suggest a need for better patient selection and treatment sequencing optimization. In North America, the main barriers in establishing similar protocols result from national liver graft shortage, which represents an issue of competing resources when indications have yet to be well defined. Evolving strategies in transplantation, such as the utilization of marginal liver grafts and living donor liver transplantation might constitute potential solutions.

SUMMARY

Evidence suggests a potential survival benefit of liver transplantation for a subset of patients with unresectable liver-limited CRLM. Further prospective trials are needed to clarify the role and feasibility of this treatment strategy in oncotransplantation.

Results of Adult Living Donor Liver Transplantation with Sixth-Decade Donors: A Propensity Score Matching Study in a High-Volume Institution

BACKGROUND We assessed the prognostic impact of donor age on the outcome of adult living donor liver transplantation (LDLT). MATERIAL AND METHODS The study population comprised adult donor and recipients of right lobe grafts for LDLT performed from January 2005 to December 2016. There were 35 living donors aged ≥50 years (old-age donor group). As a control group, donors in their 20s (young-age donor group) were selected after one-to-one propensity score matching based on sex, model for end-stage liver disease (MELD) score, and primary diagnosis. RESULTS Donor age was 52.5±1.5 years versus 25.4±3.1 years in the old- and young-age donor groups, respectively. Remnant volumes of the 2 groups were 38.9±3.0% versus 38.1±2.9%, respectively (p=0.98). One-month regeneration rate of the remnant liver was 101.1±10.6% versus 104.5±11.8%, respectively (p=0.08), and there was no significant difference in the incidences of donor complications. Mean MELD score was 15 versus 14, respectively (p=0.82). Graft-to-recipient weight ratio was 1.02±0.43 versus 0.91±0.63, respectively (p=0.28). In the recipients, biliary complication occurred in 11.4% versus 8.6%, respectively (p=0.12), and there was no difference in 5-year survival rates of both groups (p=0.15). The 1-week and 1-month regeneration rates of the remnant left liver were 71.6±9.9% and 100.1±10.6% in the old-age group, respectively, whereas those were 80.2±12.1% and 104.5±11.8% in the young-age group, respectively (p=0.08). CONCLUSIONS Right lobe grafts from donors aged ≥50 years showed the usual recovery of graft function but rather delayed liver regeneration. Thus, old-aged donors should be selected prudently after consideration of hepatic resection rate, graft size, and hepatic steatosis.

Systematic review and meta-analysis of liver transplantation using grafts from deceased donors aged over 70 years

INTRODUCTION

Due to the current organ shortage, nearly 20% of patients die waiting for a liver transplant (LT). The average donor age is on the rise, and grafts from elderly donors are offered as extended criteria grafts.

METHODS

This is a meta-analysis comparing the outcome differences of adult patients undergoing LT using grafts from <70-year-old donors vs >70-year-old donors. The primary end-points were graft and patient survival. Secondary outcomes were biliary and vascular complications as well as graft function. The odds ratio (OR) is a summary statistic with the corresponding 95% confidence interval; P < .05 was considered to be statistically significant.

RESULTS

Eight nonrandomized comparative studies with 4376 LT recipients were included. About 79.9% and 20.1% of the grafts were from <70-year-old and >70-year-old donors, respectively. Graft survival at 1 year was similar between the two groups (P = .11), but there was better 3-year and 5-year graft survival in the >70-year-old group (P = .006 and P < .0001, respectively). Patient survival was also similar between the groups at 1 year (P = .54), but with better survival at 3-year and 5-year follow-ups (P = .007 and P < .0001, respectively) in the >70-year-old group. There were no statistically significant differences in the incidence of biliary, vascular, and graft functional-related complications.

CONCLUSION

Liver grafts from selected >70-year-old donors do not pose added organ-specific risks and thus have comparable transplantation outcomes.

The use of old donors in liver transplantation

The process of ageing has an impact on the entire human body including the organ systems. In transplantation, professionals are daily faced with risk assessment of suitable donor offers , whether to accept a liver graft for a specific recipient. In this context, livers from elderly donors are more frequently accepted for transplantation, to increase the donor pool and compensate the high waiting list mortality. In the current practice it is not unusual to accept 60-year old donor livers for transplantation, as the donor demographics have significantly changed over the years. However, controversy exists regarding the use of livers from donors above 70 or 80 years, particular in combination with other risk factors, e.g. liver steatosis, warm ischaemia or long cold storage. This review focuses first on the impact of ageing on liver morphology and function. Second, we will highlight outcome after transplantation from elderly donors. Finally, we describe further risk factors and donor-recipient selection under the scope of old donor organs and include our institutional experience and policy.

Factors associated with long-term survival after liver transplantation: A retrospective cohort study

AIM

To identify predictive factors associated with long-term patient and graft survival (> 15 years) in liver transplant recipients.

METHODS

Medical charts of all de novo adult liver transplant recipients (n = 140) who were transplanted in Hamburg between 1997 and 1999 were retrospectively reviewed. In total, 155 transplantations were identified in this time period (15 re-transplantations). Twenty-six orthotopic liver transplant (OLT) recipients were early lost to follow-up due to moving to other places within 1 year after transplantation. All remaining 114 patients were included in the analysis. The following recipient factors were analysed: Age, sex, underlying liver disease, pre-OLT body mass index (BMI), and levels of alanine aminotransferase (ALT), bilirubin, creatinine and gamma-glutamyltransferase (gamma-GT), as well as warm and cold ischemia times. Furthermore, the following donor factors were assessed: Age, BMI, cold ischemia time and warm ischemia time. All surviving patients were followed until December 2014. We divided patients into groups according to their underlying diagnosis: (1) hepatocellular carcinoma (n = 5, 4%); (2) alcohol toxic liver disease (n = 25, 22.0%); (3) primary sclerosing cholangitis (n = 6, 5%); (4) autoimmune liver diseases (n = 7, 6%); (5) hepatitis C virus cirrhosis (n = 15, 13%); (6) hepatitis B virus cirrhosis (n = 21, 19%); and (7) other (n = 35, 31%). The group “other” included rare diagnoses, such as acute liver failure, unknown liver failure, stenosis and thrombosis of the arteria hepatica, polycystic liver disease, Morbus Osler and Caroli disease.

RESULTS

The majority of patients were male (n = 70, 61%). Age and BMI at the time point of transplantation ranged from 16 years to 69 years (median: 53 years) and from 15 kg/m² to 33 kg/m² (median: 24), respectively. Sixty-six OLT recipients (58%) experienced a follow-up of 15 years after transplantation. Recipient’s age (P = 0.009) and BMI (P = 0.029) were identified as risk factors for death by χ²-test. Kaplan-Meier analysis confirmed BMI or age above the median as predictors of decreased long-term survival (P = 0.008 and P = 0.020). Hepatitis B as underlying disease showed a trend for improved long-term survival (P = 0.049, χ²-test, P = 0.055; Kaplan-Meier analysis, Log rank). Pre-transplant bilirubin, creatinine, ALT and gamma-GT levels were not associated with survival in these patients of the pre-era of the model of end stage liver disease.

CONCLUSION

The recipients’ age and BMI were predictors of long-term survival after OLT, as well as hepatitis B as underlying disease. In contrast, donors’ age and BMI were not associated with decreased survival. These findings indicate that recipient factors especially have a high impact on long-term outcome after liver transplantation.

Impairment of Host Liver Repopulation by Transplanted Hepatocytes in Aged Rats and the Release by Short-Term Growth Hormone Treatment

Hepatocyte transplantation is an alternative to whole liver transplantation. Yet, efficient liver repopulation by transplanted hepatocytes is low in livers of old animals. This restraint might be because of the poor proliferative capacity of aged donor hepatocytes or the regenerative impairment of the recipient livers. The age-dependent liver repopulation by transplanted wild-type hepatocytes was investigated in juvenile and senescent rats deficient in dipeptidyl-peptidase IV. Repopulation was quantified by flow cytometry and histochemical estimation of dipeptidyl-peptidase IV enzyme activity of donor cells in the negative host liver. As a potential pathway involved, expression of cell cycle proteins was assessed. Irrespective of the age of the donor hepatocytes, large cell clusters appeared in juvenile, but only small clusters in senescent host livers. Because juvenile and senescent donor hepatocytes were likewise functional, host-derived factor(s) impaired senescent host liver repopulation. Growth hormone levels were significantly higher in juvenile than in senescent rats, suggesting that growth hormone might promote host liver repopulation. Indeed, short-term treatment with growth hormone augmented senescent host liver repopulation involving the growth hormone-mediated release of the transcriptional blockade of genes associated with cell cycle progression. Short-term growth hormone substitution might improve liver repopulation by transplanted hepatocytes, thus augmenting the therapeutic benefit of clinical hepatocyte transplantation in older patients.

Liver function declines with increased age

INTRODUCTION

Age itself is not considered a contraindication for high impact surgery. However, the aging process of the liver remains largely unknown. This study evaluates age-dependent changes in liver function using a quantitative liver function test.

METHODS

Between January 2005 and December 2014, 508 patients underwent (99m)Tc-mebrofenin hepatobiliary scintigraphy (HBS) for the assessment of liver function. These included 203 patients with healthy livers (group A) and 57 patients with HCC and Child-Pugh A (group B). (99m)Tc-mebrofenin-uptake-rate of the whole liver corrected for body surface area (cMUR) was calculated for all patients. Linear regression analysis was performed to assess the relationship between age and cMUR.

RESULTS

The mean cMUR was 8.50 ± 2.05%/min/m(2) and 6.94 ± 2.03%/min/m(2) in group A and B, respectively. A negative linear correlation was found between patient's age and cMUR in group A, r = 0.244, p = 0.000. In group B, there was no correlation between age and cMUR, however, a trend in decline of liver function with age was noted.

CONCLUSION

This study shows that liver function deteriorates with age. Since the regenerative capacity of the liver correlates with liver function, this finding should be taken into account when assessing surgical risk in patients considered for major liver resection.

Kidney and liver transplantation in the elderly

BACKGROUND

Transplant surgery is facing a shortage of deceased donor organs. In response, the criteria for organ donation have been extended, and an increasing number of organs from older donors are being used. For recipients, the benefits of transplantation are great, and the growing ageing population has led to increasing numbers of elderly patients being accepted for transplantation.

METHODS

The literature was reviewed to investigate the impact of age of donors and recipients in abdominal organ transplantation, and to highlight aspects of the fine balance in donor and recipient selection and screening, as well as allocation policies fair to young and old alike.

RESULTS

Overall, kidney and liver transplantation from older deceased donors have good outcomes, but are not as good as those from younger donors. Careful donor selection based on risk indices, and potentially biomarkers, special allocation schemes to match elderly donors with elderly recipients, and vigorous recipient selection, allows good outcomes with increasing age of both donors and recipients. The results of live kidney donation have been excellent for donor and recipient, and there is a trend towards inclusion of older donors. Future strategies, including personalized immunosuppression for older recipients as well as machine preservation and reconditioning of donor organs, are promising ways to improve the outcome of transplantation between older donors and older recipients.

CONCLUSION

Kidney and liver transplantation in the elderly is a clinical reality. Outcomes are good, but can be optimized by using strategies that modify donor risk factors and recipient co-morbidities, and personalized approaches to organ allocation and immunosuppression.

Q-FISH measurement of hepatocyte telomere lengths in donor liver and graft after pediatric living-donor liver transplantation: donor age affects telomere length sustainability

Along with the increasing need for living-donor liver transplantation (LDLT), the issue of organ shortage has become a serious problem. Therefore, the use of organs from elderly donors has been increasing. While the short-term results of LDLT have greatly improved, problems affecting the long-term outcome of transplant patients remain unsolved. Furthermore, since contradictory data have been reported with regard to the relationship between donor age and LT/LDLT outcome, the question of whether the use of elderly donors influences the long-term outcome of a graft after LT/LDLT remains unsettled. To address whether hepatocyte telomere length reflects the outcome of LDLT, we analyzed the telomere lengths of hepatocytes in informative biopsy samples from 12 paired donors and recipients (grafts) of pediatric LDLT more than 5 years after adult-to-child LDLT because of primary biliary atresia, using quantitative fluorescence in situ hybridization (Q-FISH). The telomere lengths in the paired samples showed a robust relationship between the donor and grafted hepatocytes (r = 0.765, p = 0.0038), demonstrating the feasibility of our Q-FISH method for cell-specific evaluation. While 8 pairs showed no significant difference between the telomere lengths for the donor and the recipient, the other 4 pairs showed significantly shorter telomeres in the recipient than in the donor. Multiple regression analysis revealed that the donors in the latter group were older than those in the former (p = 0.001). Despite the small number of subjects, this pilot study indicates that donor age is a crucial factor affecting telomere length sustainability in hepatocytes after pediatric LDLT, and that the telomeres in grafted livers may be elongated somewhat longer when the grafts are immunologically well controlled.

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.

The marginal liver donor--an update

The number of patients awaiting liver transplantation keeps steadily rising with no corresponding rise in suitable grafts for transplantation. There also is an increasing trend of patients dying or being taken off waiting lists because of deterioration while waiting for a transplant. Over the preceding years the use of marginal grafts in liver transplantation has been driven by the critical shortage of donor organs and by emerging data that their use has resulted in a favourable outcome. This review revisits the factors defining marginality of a graft, and the issues faced by transplant units in making the decision to use such a graft. It also looks at the innovations in transplantation geared towards increasing the donor pool and the resulting issues of matching marginal grafts to suitable recipients.

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

BACKGROUND

The question of whether donor age negatively impacts recipient outcome in adult-to-adult living donor liver transplantation (LDLT) is rarely discussed. The aim of this study was to evaluate the impact of older donor age (50 years or older) on recipient outcomes in adult-to-adult LDLT.

METHODS

LDLT data were retrospectively evaluated from our 299 LDLT cases in 297 recipients, which were divided into 2 groups: a younger group (group Y, donor age<50, n=237) and an older group (Group O, donor age>or=50, n=62). Clinical parameters of both recipients and donors were comparable between groups.

RESULTS

There was no difference between the groups in patient survival or postoperative complications of either donors or recipients. In recipients, graft regeneration was significantly impaired in Group O. Graft function, including protein synthesis and cholestasis, was comparable between the 2 groups.

CONCLUSION

Although the regeneration capacity of aged grafts was impaired, the function of grafts from older donors was comparable to that of those from younger donors. There was no difference in the clinical outcomes between the groups.

Minimizing risk associated with elderly liver donors by matching to preferred recipients

Elderly liver donors (ELDs) represent a possible expansion of the donor pool, although there is great reluctance to use ELDs because of reports that increasing donor age predicts graft loss and patient death. The goal of this study was to identify a subgroup of recipients who would be least affected by increased donor age and thus best suited to receive grafts from ELDs. A national registry of deceased donor liver transplants from 2002-2005 was analyzed. ELDs aged 70-92 (n = 1043) were compared with average liver donors (ALDs) aged 18-69 (n = 15,878) and ideal liver donors (ILDs) aged 18-39 (n = 6842). Recipient factors that modified the effect of donor age on outcomes were identified via interaction term analysis. Outcomes in recipient subgroups were compared using Kaplan-Meier survival analysis. Recipients preferred for ELD transplants were determined to be first-time recipients over the age of 45 with body mass index <35, non-status 1 registration, cold ischemic time <8 hours, and either hepatocellular carcinoma or an indication for transplantation other than hepatitis C. In preferred recipients, there were no differences in outcomes when ELD livers were used (3-year graft survival: ELD 75%, ALD 75%, ILD 77%, P > 0.1; 3-year patient survival: ELD 81%, ALD 80%, ILD 81%, P > 0.1). In contrast, there were significantly worse outcomes when ELD livers were used in nonpreferred recipients (3-year graft survival: ELD 50%, ALD 71%, ILD 75%, P < 0.001; 3-year patient survival: ELD 64%, ALD 77%, ILD 80%, P < 0.001).

CONCLUSION

The risks of ELDs can be substantially minimized by appropriate recipient selection.