Survival after liver transplantation for hepatocellular carcinoma in the model for end-stage liver disease and pre-model for end-stage liver disease eras and the independent impact of hepatitis C virus

A Review of the Current State of Liver Transplantation Disparities

Equity in access is one of the core goals of the Organ Procurement and Transplant Network (OPTN). However, disparities in liver transplantation have been described since the passage of the National Organ Transplant Act, which established OPTN in the 1980s. During the past few decades, several efforts have been made by the United Network for Organ Sharing (UNOS) to address disparities in liver transplantation with notable improvements in many areas. Nonetheless, disparities have persisted across insurance type, sex, race/ethnicity, geographic area, and age. African Americans have lower rates of referral to transplant centers, females have lower rates of transplantation from the liver waiting list than males, and public insurance is associated with worse posttransplant outcomes than private insurance. In addition, pediatric candidates and older adults have a disadvantage on the liver transplant waiting list, and there are widespread regional disparities in transplantation. Given the large degree of inequity in liver transplantation, there is a tremendous need for studies to propose and model policy changes that may make the liver transplant system more just and equitable.

Impact of chronic hepatitis C virus infection on the survival of patients with oropharyngeal cancer

BACKGROUND

Although an association between hepatitis C virus (HCV) infection and oropharyngeal cancers (OPCs) has been reported, to the authors' knowledge the clinical significance of this epidemiological finding remains unknown. Therefore, the authors analyzed the oncologic outcomes of HCV-infected patients with OPCs.

METHODS

In this retrospective cohort study, all patients with OPCs who were seen at The University of Texas MD Anderson Cancer Center between January 2004 and December 2015 were reviewed. HCV infection was defined as detectable HCV RNA in the serum. Five-year overall survival and progression-free survival rates were compared between patients infected with HCV and those not infected.

RESULTS

A total of 161 patients were examined. The majority of the patients were white (141 patients; 88%) and male (132 patients; 82%) and had TNM stage III or IV disease (147 patients; 91%). The OPC involved the tonsils (83 patients; 52%), base of the tongue (67patients; 42%), or the soft palate (11 patients; 7%). The median follow-up after an OPC diagnosis was 3 years (range, 1-13 years). HCV-infected patients (25 patients) and HCV-uninfected patients (136 patients) were comparable with regard to smoking and alcohol status. In multivariate analysis, HCV was associated with increased cancer-specific mortality (hazard ratio, 2.15; 95% confidence interval, 1.08-6.85 [P = .02]) and risk of OPC progression (hazard ratio, 5.42; 95% confidence interval, 2.64-11.14 [P = .0008]) independent of age and cirrhosis status. Antivirals were administered after the diagnosis of OPC in 8 of the 25 HCV-infected patients (32%). HCV-infected patients who received antivirals were found to have better 5-year overall survival (70% vs 12%; P = .005) and progression-free survival (72% vs 19%; P = .005) compared with patients who did not.

CONCLUSIONS

The early detection of HCV is important in patients with OPC because this infection may affect their oncologic outcomes. Cancer 2018;124:960-5. © 2017 American Cancer Society.

The Geography of Primary Hepatic Neoplasms Treatments in Canada: Changes in Latitudes and Changes in Attitudes

BACKGROUND

Studies on treatment modalities for primary hepatic neoplasms (PHN) in Canada are lacking. Our primary aim was to analyze the age-standardized incidence of hepatic resection, ablation, transplantation, and embolization for PHN between 2002 and 2013. Secondary aim was to evaluate temporal trends for these treatment modalities.

STUDY DESIGN

National Canadian Cancer Registries were accessed for relevant epidemiological data. Age-standardized incidence of treatment ratios (SIRs) was calculated and comparisons were performed for Atlantic Canada, Ontario, the Prairies, and British Columbia.

RESULTS

British Columbia recorded the highest SIRs for ablation (1.9; 95% CI 1.8-2.0), hepatic resection (1.2; 95% CI 1.1-1.3), and transarterial locoregional therapies (2.8; 95% CI 2.4-3.2). For hepatic resection, the lowest SIR was found in Atlantic Canada (0.7; 95% CI 0.6-0.9), while the Prairies recorded the lowest estimate for transarterial therapies (0.2; 95% CI 0.1-0.4). Liver transplantation had the highest SIR in Ontario (1.5; 95% CI 1.3-1.6) and the lowest SIR in British Columbia. No significant temporal changes in SIRs were observed for any of the treatments except for transarterial therapies.

CONCLUSIONS

Treatment of PHN in Canada differs by geography. Variations might be due to differences in expertise or access to therapeutic modalities.

Treatment of patients waitlisted for liver transplant with all-oral direct-acting antivirals is a cost-effective treatment strategy in the United States

All-oral direct acting antivirals (DAAs) have been shown to have high safety and efficacy in treating patients with hepatitis C virus (HCV) awaiting liver transplant (LT). However, there is limited empirical evidence comparing the health and economic outcomes associated with treating patients pre-LT versus post-LT. The objective of this study was to analyze the cost-effectiveness of pre-LT versus post-LT treatment with an all-oral DAA regimen among HCV patients with hepatocellular carcinoma (HCC) or decompensated cirrhosis (DCC). We constructed decision-analytic Markov models of the natural disease progression of HCV in HCC patients and DCC patients waitlisted for LT. The model followed hypothetical cohorts of 1,000 patients with a mean age of 50 over a 30-year time horizon from a third-party US payer perspective and estimated their health and cost outcomes based on pre-LT versus post-LT treatment with an all-oral DAA regimen. Transition probabilities and utilities were based on the literature and hepatologist consensus. Sustained virological response rates were sourced from ASTRAL-4, SOLAR-1, and SOLAR-2. Costs were sourced from RedBook, Medicare fee schedules, and published literature. In the HCC analysis, the pre-LT treatment strategy resulted in 11.48 per-patient quality-adjusted life years and $365,948 per patient lifetime costs versus 10.39 and $283,696, respectively, in the post-LT arm. In the DCC analysis, the pre-LT treatment strategy resulted in 9.27 per-patient quality-adjusted life years and $304,800 per patient lifetime costs versus 8.7 and $283,789, respectively, in the post-LT arm. As such, the pre-LT treatment strategy was found to be the most cost-effective in both populations with an incremental cost-effectiveness ratio of $74,255 (HCC) and $36,583 (DCC). Sensitivity and scenario analyses showed that results were most sensitive to the utility of patients post-LT, treatment sustained virological response rates, LT costs, and baseline Model for End-Stage Liver Disease score (DCC analysis only).

CONCLUSION

The timing of initiation of antiviral treatment for HCV patients with HCC or DCC relative to LT is an important area of clinical and policy research; our results indicate that pre-LT treatment with a highly effective, all-oral DAA regimen provides the best health outcomes and is the most cost-effective strategy for the treatment of HCV patients with HCC or DCC waitlisted for LT. (Hepatology 2017;66:46-56).

Model for end-stage liver disease score and MELD exceptions: 15 years later

The model for end-stage liver disease (MELD) score has been used as an objective scale of disease severity for management of patients with end-stage liver disease; it currently serves as the basis of an urgency-based organ-allocation policy in several countries. Implementation of the MELD score led to a reduction in waiting-list registration and waiting-list mortality and an increase in the number of deceased-donor transplants without adversely affecting long-term outcomes after liver transplantation (LT). The MELD score has been used for management of non-transplant patients with chronic liver disease. MELD exceptions serve as a mechanism to advance the needs of subsets of patients with liver disease not adequately addressed by MELD-based organ allocation. Several models have been proposed to refine and improve the MELD score as the environment within which it operates continues to evolve toward transplantation for sicker patients. The MELD score continues to serve and be used as a template to improve upon as an objective gauge of disease severity and as a metric enabling optimization of allocation of scarce donor organs for LT.

Hepatitis B and C in African Americans: current status and continued challenges

Viral hepatitis remains a public health concern in the United States, resulting in excess morbidity and mortality for the individual and representing a burden to societies as evidenced by billions of dollars in health care expenditures. As with many chronic diseases, race and ethnicity influence various aspects of disease pathogenesis, including mechanisms of persistence, disease progression, disease sequelae, and response to therapy. For hepatitis B and C infections, African Americans disproportionately bear a large burden of disease in the United States. The role and importance of African American race, however, have been less well-characterized in the literature among the population of viral hepatitis-infected individuals. The differences in epidemiology, manifestations of liver disease, response to therapy, and differential trends in liver transplantation in African Americans compared with other racial and ethnic groups deserve special attention. This review will address the current status of hepatitis B and C infection in African Americans in the United States and identify some of the remaining challenges in diagnosis, characterization of natural history, and treatment. For the purposes of this review, the terms African American and black will be used interchangeably throughout the text.

Hepatitis C infection and hepatocellular carcinoma in liver transplantation: a 20-year experience

BACKGROUND

Hepatitis C infection (HCV) and hepatocellular carcinoma (HCC), the two main causes of liver transplantation (LT), have reduced survival post-LT. The impact of HCV, HCC and their coexistence on post-LT survival were assessed.

METHODOLOGY

All 601 LT patients from 1992 to 2011 were reviewed. Those deceased within 30 days (n = 69) and re-transplants (n = 49) were excluded. Recipients were divided into four groups: (a) HCC-/HCV-(n = 252) (b) HCC+/HCV- (n = 58), (c) HCC-/HCV+ (n = 106) and (d) HCC+/HCV+ (n = 67). Demographics, the donor risk index (DRI), Model for End-Stage Liver Disease (MELD) score, survival, complications and tumour characteristics were collected. Statistical analysis included anova, chi-square, Fisher's exact tests and Cox and Kaplan-Meier for overall survival.

RESULTS

Groups were comparable with regards to baseline characteristics, but HCC patients were older. After adjusting for age, MELD, gender and the donor risk index (DRI), survival was lower in the HCC+/HCV+ group (59.5% at 5 yrs) and the hazard ratio (HR) was 1.90 [95% confidence interval (CI),1.24-2.95, P = 0.003] and 1.45 (95% CI, 0.99-2.12, P = 0.054) for HCC-/HCV+. HCC survival was similar to controls (HR 1.18, 95% CI, 0.71-1.93, P = 0.508). HCC+/HCV- patients exceeded the Milan criteria (50% versus 31%, P < 0.04) and had more micro-vascular invasion (37.5% versus 20.6%, P = 0.042). HCC+/HCV+ versus HCC+/HCV- survival remained lower (HR 1.94, 95% CI, 1.06-3.81, P = 0.041) after correcting for tumour characteristics and treatment.

CONCLUSION

HCV patients had lower survival post-LT. HCC alone had no impact on survival. Patient survival decreased in the HCC+/HCV+ group and this appears to be as a consequence of HCV recurrence.

Low expression of PAI-2 as a novel marker of portal vein tumor thrombosis and poor prognosis in hepatocellular carcinoma

BACKGROUND

Plasminogen activator inhibitor (PAI)-2 was previously shown to be less frequently expressed in hepatocellular carcinoma (HCC). The present study was designed to investigate the clinical, pathological, and prognostic significance of PAI-2 expression in HCC.

METHODS

Expression of PAI-2 was detected immunohistochemically for specimens from 78 patients with HCC after hepatic resection and correlated with clinicopathological features and patient survival. Risk factors of portal vein tumor thrombosis (PVTT) were also analyzed.

RESULTS

Positive PAI-2 staining was observed in tumor and non-tumor tissues from 21 (26.9%) and 56 (71.8%) patients, respectively. Plasminogen activator inhibitor-2 negativity in tumor tissues was significantly associated with PVTT, with a high sensitivity not only in univariate analysis but also in multivariate analysis. In addition, positive PAI-2 staining was related to smaller tumor size and prolonged patient survival. The Cox regression model identified intratumoral PAI-2 staining as an independent prognosticator in patients with HCC after resection.

CONCLUSIONS

Our data demonstrated that low expression of PAI-2 serves as a novel marker of PVTT and poor prognosis in HCC.

Liver transplantation in the critically ill: a multicenter Canadian retrospective cohort study

Introduction

Critically ill cirrhosis patients awaiting liver transplantation (LT) often receive prioritization for organ allocation. Identification of patients most likely to benefit is essential. The purpose of this study was to examine whether the Sequential Organ Failure Assessment (SOFA) score can predict 90-day mortality in critically ill recipients of LT and whether it can predict receipt of LT among critically ill cirrhosis listed awaiting LT.

Methods

We performed a multicenter retrospective cohort study consisting of two datasets: (a) all critically-ill cirrhosis patients requiring intensive care unit (ICU) admission before LT at five transplant centers in Canada from 2000 through 2009 (one site, 1990 through 2009), and (b) critically ill cirrhosis patients receiving LT from ICU (n = 115) and those listed but not receiving LT before death (n = 106) from two centers where complete data were available.

Results

In the first dataset, 198 critically ill cirrhosis patients receiving LT (mean (SD) age 53 (10) years, 66% male, median (IQR) model for end-stage liver disease (MELD) 34 (26-39)) were included. Mean (SD) SOFA scores at ICU admission, at 48 hours, and at LT were 12.5 (4), 13.0 (5), and 14.0 (4). Survival at 90 days was 84% (n = 166). In multivariable analysis, only older age was independently associated with reduced 90-day survival (odds ratio (OR), 1.07; 95% CI, 1.01 to 1.14; P = 0.013). SOFA score did not predict 90-day mortality at any time. In the second dataset, 47.9% (n = 106) of cirrhosis patients listed for LT died in the ICU waiting for LT. In multivariable analysis, higher SOFA at 48 hours after admission was independently associated with lower probability of receiving LT (OR, 0.89; 95% CI, 0.82 to 0.97; P = 0.006). When including serum lactate and SOFA at 48 hours in the final model, elevated lactate (at 48 hours) was also significantly associated with lower likelihood of receiving LT (0.32; 0.17 to 0.61; P = 0.001).

Conclusions

SOFA appears poor at predicting 90-day survival in critically ill cirrhosis patients after LT, but higher SOFA score and elevated lactate 48 hours after ICU admission are associated with a lower probability receiving LT. Older critically ill cirrhosis patients (older than 60) receiving LT have worse 90-day survival and should be considered for LT with caution.

Employment of MELD score for the prediction of survival after liver transplantation

OBJECTIVE

To assess the overall accuracy of the preoperative MELD score for predicting survival after liver transplantation (LT) and appraise medium-term (24 months) predictors of survival.

METHODS

We conducted a cross-sectional study including patients transplanted by the Department of General Surgery and Liver Transplantation of the Oswaldo Cruz University Hospital, University of Pernambuco, between July 15th, 2003 and July 14th, 2009. We used analysis of area under ROC (receiver operating characteristic) as a summary measure of the performance of the MELD score and assessed predictors of medium-term survival using univariate and multivariate analysis.

RESULTS

The cumulative survival of three, six, 12 and 24 months of the 208 patients studied was 85.1%, 79.3%, 74.5% and 71.1%, respectively. The preoperative MELD score showed a low discriminatory power for predicting survival after TH. By univariate analysis, we identified intraoperative transfusion of red blood cells (p <0.001) and platelets (p = 0.004) and type of venous hepatocaval anastomosis (p = 0.008) as significantly related to medium-term survival of the patients studied. However, by multivariate analysis only red blood cell transfusion was a significant independent predictor of outcome.

CONCLUSION

The MELD score showed low overall accuracy for predicting post-transplant survival of patients studied, among which only intraoperative transfusion of red blood cells was identified as an independent predictor of survival in the medium term after TH.

Modulation of immune responses following solid organ transplantation by microRNA

Organ transplantation, an accepted treatment for end stage organ failure, is often complicated by allograft rejection and disease recurrence. In this review we will discuss the potential role of microRNAs in allograft immunity especially leading to rejection of the transplanted organ. microRNAs (miRNAs), originally identified in C. elegans, are short non-coding 21-24 nucleotide sequences that bind to its complementary sequences in functional messenger RNAs and inhibits post-translational processes through RNA duplex formation resulting in gene silencing (Lau et al., 2001). Gene specific translational silencing by miRNAs regulates pathways for immune responses such as development of innate immunity, inflammation, T-cell and B-cell differentiation and signaling that are implicated in various stages of allograft rejection. miRNAs also play a role in development of post-transplant complicacies like fibrosis, cirrhosis, carcinogenesis often leading to graft loss and poor patient outcome. Recent advancements in the methods for detecting and quantifying miRNA in tissue biopsies, as well as in serum and urine samples, has led to identification of specific miRNA signatures in patients with allograft rejection and have been utilized to predict allograft status and survival. Therefore, miRNAs play a significant role in post-transplant events including allograft rejection, disease recurrence and tumor development impacting patient outcome.

Non-cancerous prognostic factors of hepatocellular carcinoma after liver transplantation

PURPOSE

To explore non-cancerous factors that may be related with medium-term survival (24 months) after liver transplantation (LT) in this data from northeast Brazil.

METHODS

A cross-sectional study was carried out in patients who underwent deceased-donor orthotopic LT because hepatocellular carcinoma (HCC) at the University of Pernambuco, Brazil. Non-cancerous factors (i.e.: donor-, receptor-, surgery- and center-related variables) were explored as prognostic factors of medium-term survival using univariate and multivariate approachs.

RESULTS

Sixty-one patients were included for analysis. Their three, six, 12 and 24-month overall cumulative survivals were 88.5%, 80.3%, 73.8% and 65.6%, respectively. Our univariate analysis identified red blood cell transfusion (Exp[b]=1.26; p<0.01) and hepato-venous reconstruction technique (84.6% vs. 51.4%, p<0.01; respectively for piggyback and conventional approaches) as significantly related to post-LT survival. The multivariate analysis confirmed the hepato-venous reconstruction technique was an independent prognostic factor.

CONCLUSION

The piggyback technique was related to improved medium-term survival of hepatocellular carcinoma patients after liver transplantation in this northeast Brazilian sample.

Model for end-stage liver disease: end of the first decade

The Model for End-stage Liver Disease (MELD) score is the basis for allocation of liver allografts for transplantation in the United States. The MELD score, as an objective scale of disease severity, is also used in the management of patients with chronic liver disease in the nontransplant setting. Several models have been proposed to improve the MELD score. The authors believe that the MELD score is, by design, continually evolving and lends itself to continued refinement and improvement to serve as a metric to optimize organ allocation in the future.

Can the dropout risk of candidates with hepatocellular carcinoma predict survival after liver transplantation?

In the last US national conference on liver transplantation for hepatocellular carcinoma (HCC), a continuous priority score, that incorporates model for end-stage liver disease (MELD), alpha-fetoprotein and tumor size, was recommended to ensure a more equitable liver allocation. However, prioritizing highest alpha-fetoprotein levels or largest tumors may select lesions at a higher risk for recurrence; similarly, patients with higher degree of liver failure could have lower postoperative survival. Data from 300 adult HCC recipients were reviewed and the proposed HCC-MELD equation was applied to verify if it can predict post-transplantation survival. The 5-year survival and recurrence rates after transplantation were 72.8 and 13.5%, respectively. Cox regression analysis confirmed HCC-MELD as predictive of both postoperative survival and recurrence (p < 0.001). The 5-year predicted survival and recurrence rates were plotted against the HCC-MELD-based dropout probability: the higher the dropout probability while on waiting list, the lower the predicted survival after transplantation, that is worsened by hepatitis C positivity; similarly, the higher the predicted HCC recurrence rate after transplantation. The HCC priority score could predict the postoperative survival of HCC recipients and could be useful in selecting patients with greater possibilities of survival, resulting in higher post-transplantation survival rates of HCC populations.

Impact of MELD allocation policy on survival outcomes after liver transplantation: a single-center study in northeast Brazil

OBJECTIVE

To analyze the impact of model for end-stage liver disease (MELD) allocation policy on survival outcomes after liver transplantation (LT).

INTRODUCTION

Considering that an ideal system of grafts allocation should also ensure improved survival after transplantation, changes in allocation policies need to be evaluated in different contexts as an evolutionary process.

METHODS

A retrospective cohort study was carried out among patients who underwent LT at the University of Pernambuco. Two groups of patients transplanted before and after the MELD allocation policy implementation were identified and compared using early postoperative mortality and post-LT survival as end-points.

RESULTS

Overall, early postoperative mortality did not significantly differ between cohorts (16.43% vs. 8.14%; p = 0.112). Although at 6 and 36-months the difference between pre-vs. post-MELD survival was only marginally significant (p = 0.066 and p = 0.063; respectively), better short, medium and long-term post-LT survival were observed in the post-MELD period. Subgroups analysis showed special benefits to patients categorized as nonhepatocellular carcinoma (non-HCC) and moderate risk, as determined by MELD score (15-20).

DISCUSSION

This study ensured a more robust estimate of how the MELD policy affected post-LT survival outcomes in Brazil and was the first to show significantly better survival after this new policy was implemented. Additionally, we explored some potential reasons for our divergent survival outcomes.

CONCLUSION

Better survival outcomes were observed in this study after implementation of the MELD criterion, particularly amongst patients categorized as non-HCC and moderate risk by MELD scoring. Governmental involvement in organ transplantation was possibly the main reason for improved survival.

Survival tree and MELD to predict long term survival in liver transplantation waiting list

MELD score is a formula based on laboratory variables used as a predictor of short-term mortality index in cirrhotic patients. It is applied to allocate patients in liver transplantation waiting list in many countries. However, MELD score cutoff point accuracy to predict long term mortality has not been statistically evaluated. The aim of this study was to analyze the MELD score and other variables related to long-term mortality using a new model: the Survival Tree analysis. The variables considered in this study were obtained at the time of liver transplantation list enrollment. The graphical representation of the survival trees showed that MELD 16 was the most statistically significant mortality cutoff point. The results were compatible with the MELD cutoff point reported in the clinical literature. This methodology can be extended to identify significant cutoff points related to other diseases whose severity is not necessarily expressed by MELD.

Targeting mitogen-activated protein kinase kinase with the inhibitor PD0325901 decreases hepatocellular carcinoma growth in vitro and in mouse model systems

Hepatocellular carcinoma (HCC) is a common cause of death from solid organ malignancy worldwide. Extracellular signal-regulated/mitogen-activated protein kinase kinase (MEK) signaling is a critical growth regulatory pathway in HCC. Targeting MEK with a novel small molecule inhibitor, PD0325901, may inhibit HCC tumorigenesis. PD0325901 (0.01-100 nM) inhibited growth and MEK activity in vitro in immortalized murine transforming growth factor alpha (TGF-alpha) transgenic hepatocyte (TAMH) cells, derived from the livers of TGF-alpha transgenic mice. Treatment of athymic mice bearing TAMH flank tumors with vehicle or PD0325901 (20 mg/kg) revealed a significant reduction of MEK activity ex vivo 24 hours after a single PD0325901 dose. The growth rate of TAMH flank tumors over 16 days was reduced threefold in the treatment arm (1113 +/- 269% versus 3077 +/- 483%, P < 0.01). PD0325901 exhibited similar inhibitory effects in HepG2 and Hep3B human HCC cells in vitro and in Hep3B flank tumors in vivo. To confirm this in a developmental model, MT-42 (CD-1) TGF-alpha mice were treated with vehicle or PD0325901 (20 mg/kg) for 5 weeks. Gross HCC was detected in 47% and 13.3% of the control and treatment mice, respectively. Tumor growth suppression by PD0325901 relative to vehicle was also shown by magnetic resonance imaging. These studies provide compelling preclinical evidence that targeting MEK in human clinical trials may be promising for the treatment of HCC.