Liver Allocation Policies in the USA: Past, Present, and the Future

Liver Transplant as a Treatment of Primary and Secondary Liver Neoplasms

Importance

Liver malignancies are an increasing global health concern with a high mortality. We review outcomes following liver transplant for primary and secondary hepatic malignancies.

Observations

Transplant may be a suitable treatment option for primary and secondary hepatic malignancies in well-selected patient populations.

Conclusions and Relevance

Many patients with primary or secondary liver tumors are not eligible for liver resection because of advanced underlying liver disease or high tumor burden, precluding complete tumor clearance. Although liver transplant has been a long-standing treatment modality for patients with hepatocellular carcinoma, recently transplant has been considered for patients with other malignant diagnoses. In particular, while well-established for hepatocellular carcinoma and select patients with perihilar cholangiocarcinoma, transplant has been increasingly used to treat patients with intrahepatic cholangiocarcinoma, as well as metastatic disease from colorectal liver and neuroendocrine primary tumors. Because of the limited availability of grafts and the number of patients on the waiting list, optimal selection criteria must be further defined. The ethics of organ allocation to individuals who may benefit from prolonged survival after transplant yet have a high incidence of recurrence, as well as the role of living donation, need to be further discerned in the setting of transplant oncology.

Induction Immunosuppression Does Not Worsen Tumor Recurrence After Liver Transplantation for Hepatocellular Carcinoma

BACKGROUND

Prior studies are inconsistent regarding the impact of antibody induction therapy on outcomes after liver transplantation (LT) for hepatocellular carcinoma (HCC).

METHODS

Adults transplanted with HCC exception priority were identified from February 27, 2002, to March 31, 2019, using the United Network for Organ Sharing database. Time-to-event analyses evaluated the association of antibody induction therapy (none, nondepleting induction [NDI], depleting induction [DI]) with overall post-LT patient survival and HCC recurrence. Separate multivariable models adjusted for tumor characteristics on either last exception or on explant. The interaction of induction and maintenance regimen at LT discharge was investigated.

RESULTS

Among 22 535 LTs for HCC, 17 688 (78.48%) received no antibody induction, 2984 (13.24%) NDI, and 1863 (8.27%) DI. Minimal differences in patient and tumor characteristics were noted between induction groups, and there was significant center variability in practices. NDI was associated with improved survival, particularly when combined with a calcineurin inhibitor (CNI) and antimetabolite (hazard ratio [HR] 0.73 versus no induction plus 3-drug therapy in the last exception model [ P  < 0.001]; HR 0.64 in the explant model [ P  = 0.011]). The combination of DI with CNI alone was also protective (HR 0.43; P  = 0.003). Neither NDI nor DI was associated with tumor recurrence (all P  > 0.1). However, increased HCC recurrence was observed with no induction plus CNI monotherapy (HR 1.47, P  = 0.019; versus no induction plus 3-drug therapy).

CONCLUSIONS

In conclusion, induction immunosuppression was not associated with worse post-LT outcomes in patients transplanted with HCC exception priority. An improvement in survival was possibly observed with NDI.

Outcomes of liver transplantation in non-alcoholic steatohepatitis (NASH) versus non-NASH associated hepatocellular carcinoma

BACKGROUND

Non-alcoholic steatohepatitis (NASH)-associated hepatocellular carcinoma (HCC) is a rising indication for liver transplantation. This unique population, with multiple comorbidities, has potential for worse post-transplant outcomes. We compared post-transplant survival of NASH and non-NASH HCC patients using a large cohort.

METHODS

Adults transplanted for HCC between 2008 and 2018, from United Network for Organ Sharing (UNOS) and University Health Network (UHN) databases were divided into two populations: NASH and non-NASH. Recipient characteristics and post-transplant survival were compared. Subgroup analyses were performed within and beyond Milan criteria.

RESULTS

2071 of 20,672 (10.0%) patients underwent transplantation for NASH HCC, with annual proportional increase of 1.2%UHN (p = 0.02) and 1.3%UNOS (p < 0.001). The 1-,3-,5-year post-transplant survival were 90.8%, 83.9%, 76.3% NASH HCC versus 91.9%, 82.1%, 74.9% non-NASH HCC (p = 0.94). No survival differences were observed in populations within or beyond Milan. Competing-risk analysis demonstrated no differences in risk for cardiovascular-related death (HR1.24, 95%CI 0.87-1.55, p = 0.16), or HCC recurrence-related death (HR1.21, 95%CI 0.89-1.65, p = 0.23). NASH HCC patients had lower risk of liver-related deaths (HR0.57, 95%CI 0.34-0.98, p = 0.04).

DISCUSSION

NASH HCC is a rising indication for liver transplantation. Despite demographic differences, no post-transplantation survival differences were observed between NASH and non-NASH HCC. This justifies equivalent organ allocation, irrespective of NASH status.

Hepatocellular Carcinoma, Alpha Fetoprotein, and Liver Allocation for Transplantation: Past, Present and Future

Hepatocellular carcinoma (HCC) is one of the leading indications for liver transplantation and has been the treatment of choice due to the oncologic benefit for patients with advanced chronic liver disease (AdvCLD) and small tumors for the last 25 years. For HCC patients undergoing liver transplantation, alpha fetoprotein (AFP) has increasingly been applied as an independent predictor for overall survival, disease free recurrence, and waitlist drop out. In addition to static AFP, newer studies evaluating the AFP dynamic response to downstaging therapy show enhanced prognostication compared to static AFP alone. While AFP has been utilized to select HCC patients for transplant, despite years of allocation policy changes, the US allocation system continues to take a uniform approach to HCC patients, without discriminating between those with favorable or unfavorable tumor biology. We aim to review the history of liver allocation for HCC in the US, the utility of AFP in liver transplantation, the implications of weaving AFP as a biomarker into policy. Based on this review, we encourage the US transplant community to revisit its HCC organ allocation model, to incorporate more precise oncologic principles for patient selection, and to adopt AFP dynamics to better stratify waitlist dropout risk.

Preoperative Prognostic Nutritional Index May Be a Strong Predictor of Hepatocellular Carcinoma Recurrence Following Liver Transplantation

Purpose

Malnutrition is a major risk factor of immune dysfunction and poor outcome in cancer patients. The prognostic nutritional index (PNI), which is established by serum albumin level and peripheral lymphocyte count, was shown to correlate with prognosis of hepatocellular carcinoma (HCC) patients following liver resection and non-surgical interventions. The aim of this study was to analyze the predictive value of preoperative PNI in liver transplantation (LT) patients with HCC.

Patients and Methods

A total of 123 HCC patients that underwent LT were included in the analysis. The prognostic impact of preoperatively assessed clinical factors including the PNI on post-LT outcome was analyzed by uni- and multivariate analysis.

Results

Post-transplant tumor recurrence rates were 5.1% in high-PNI (> 42) and 55.6% in low-PNI (≤ 42) patients (p < 0.001). Preoperative high-PNI could be identified as a significant and independent promoter of both recurrence-free survival (hazard ratio [HR] = 10.12, 95% CI: 3.40–30.10; p < 0.001) and overall survival (HR = 1.69, 95% CI: 1.02–2.79; p = 0.004) following LT. Apart from that low-PNI proved to be a significant and independent predictor of microvascular tumor invasion (OR = 7.71, 95% CI: 3.17–18.76; p < 0.001). In contrast, no tumor morphology features including the Milan criteria revealed an independent prognostic value.

Conclusion

Our data indicate that preoperative PNI correlates with biological tumor aggressiveness and outcome following LT in HCC patients and may therefore be useful for refining oncologic risk stratification.

The second Mexican consensus on hepatocellular carcinoma. Part II: Treatment

Hepatocellular carcinoma (HCC) is more frequently manifesting as one of the main complications of cirrhosis of the liver, its principal risk factor. There have been modifications in its incidence over the past decade, related to an epidemiologic transition in the etiology of cirrhosis, with a decrease in the prevalence of hepatitis C and an increase in nonalcoholic fatty liver disease (NAFLD) as a cause, as well as the development of HCC in the non-cirrhotic liver due to NAFLD. Genetic markers associated with the disease have been identified, and surveillance and diagnosis have improved. Regarding treatment, surgical techniques, in both resection and transplantation, have advanced and radiologic techniques, at the curative stage of the disease, have enhanced survival in those patients. And finally, there have been radical changes in the systemic approach, with much more optimistic expectations, when compared with the options available a decade ago. Therefore, the Asociación Mexicana de Hepatología decided to carry out the Second Mexican Consensus on Hepatocellular Carcinoma, which is an updated review of the available national and international evidence on the epidemiology, risk factors, surveillance, diagnosis, and treatment of the disease, to offer the Mexican physician current information on the different topics regarding hepatocellular carcinoma. In this second part of the document, the topics related to the treatment of HCC are presented.

Liver Transplant Center Size and The Impact on the Clinical Outcomes and Resource Utilization

BACKGROUND

Prior studies suggest that transplant center volume is associated with liver transplantation (LT) outcomes. We compared patient characteristics and waitlist outcomes among transplant centers in the U.S. with different volumes.

METHODS

Data for adult waitlisted candidates and LT recipients in the U.S. between 2008 and 2017 were extracted from the Scientific Registry of Transplant Recipients database. Transplant centers were categorized by transplants/year into tertiles:low-volume centers (LVCs; <20 transplantations per year)medium-volume centers (MVCs; 20-55 transplantations per year)high-volume centers (HVCs; >55 transplantations per year)Patient characteristics, waitlist outcomes, and factors associated with post-transplantation mortality were compared.

RESULTS

From 141 centers, 112,110 patients were waitlisted for LT: 6% at LVCs, 26% at MVCs, and 68% at HVCs. Patients listed in LVCs were less likely to have private insurance but had higher Medicaid and Veterans Affairs healthcare rates. Patients at LVCs were less likely to receive LT (47% vs. 53% in MVC vs. 61% in HVC), had higher transfer rates to other centers, and were more likely to be removed from the waitlist. In competing risk survival analysis, adjusted for center location, MELD score, and clinico-demographic factors, patients listed at an HVC were more likely to receive LT (aHR:1.30; 95%CI= 1.27-1.33; P<0.001). Among LT-recipients (n=62,131), receiving a transplant at an LVC was associated with higher post-LT mortality (aHR:1.16; 95%CI=1.05-1.28; P=0.003).

CONCLUSION

Patients in LVCs were less likely to receive a LT and a higher risk of post-LT death.Supplemental Visual Abstract; http://links.lww.com/TP/C274.

Race and Gender Disparity in the Surgical Management of Hepatocellular Cancer: Analysis of the Surveillance, Epidemiology, and End Results (SEER) Program Registry

BACKGROUND

The existence of race and gender disparity has been described in numerous areas of medicine. The management of hepatocellular cancer is no different, but in no other area of medicine, is the treatment algorithm more complicated by local, regional, and national health care distribution policy.

METHODS

Multivariate logistic regression and Cox-regression were utilized to analyze the treatment of patients with hepatocellular cancer registered in SEER between 1999 and 2013 to determine the incidence and effects of racial and gender disparity. Odd ratios (OR) are relative to Caucasian males, SEER region, and tumor characteristics.

RESULTS

The analysis of 57,449 patients identified the minority were female (25.31%) and African-American (16.26%). All tumor interventions were protective (p < 0.001) with respect to survival. The mean survival for all registered patients was 13.01 months with conditional analysis, confirming that African-American men were less likely to undergo ablation, resection, or transplantation (p < 0.001). Women were more likely to undergo resection (p < 0.001). African-American women had an equivalent OR for resection but had a significantly lower transplant rate (p < 0.001).

CONCLUSIONS

Utilizing SEER data as a surrogate for patient navigation in the treatment of hepatocellular cancer, our study identified not only race but gender bias with African-American women suffering the greatest. This is underscored by the lack of navigation of African-Americans to any therapy and a significant bias to navigate female patients to resection potentially limiting subsequent access to definitive therapy namely transplantation.

Survival After Treatable Hepatocellular Carcinoma Recurrence in Liver Recipients: A Nationwide Cohort Analysis

Background

Survival after post-transplant recurrence of HCC is dismal, and almost all treatments for recurrent HCC are off-labeled, without an extensive large-scale analysis. We aimed to delineate their post-recurrence courses and define benchmarks for comparing future treatment effectiveness.

Methods

Three national databases, including health insurance, catastrophic illness, and the cause of death, were linked for cohort establishment and data collection during the period from 2005 to 2016. Patients with HCC recurrence ≥6 months after transplant surgery and under treatment were recruited for survival analysis. Selection of treatment strategies for HCC recurrence after liver transplant was based on the same criteria for those without liver transplant.

Results

Of 2,123 liver transplant recipients, 349 developed HCC recurrence ≥6 months after liver transplant, and the median recurrence time was 17.8 months post-transplant. Within 2 years of treatment, 61% patients showed recurrence (early recurrence group), and survival in these patients was poorer than in the late recurrence group. According to a multivariable analysis, the transplant era before 2008 and radiofrequency ablation were associated with good prognosis, whereas receiving sorafenib and radiotherapy was associated with poor prognosis. The effect of transplant era became insignificant after stratification by recently receiving pretransplant transarterial chemoembolization.

Conclusion

Timing of recurrence and interventions used were associated with the outcomes of patients with post-transplant HCC recurrence. These data provide the benchmark and indicate the critical period and high-risk factors for further therapeutic trial consideration.

Development and validation of risk score for predicting spontaneous rupture of hepatocellular carcinoma

Purpose

Spontaneous rupture is a potentially serious complication of liver cancer. A risk score was developed and validated for predicting spontaneous rupture based on a retrospective study.

Methods

Multiple logistic regression analysis was used to study the relationship between clinical variables and spontaneous rupture. The independent rupture predictors were converted into a score based on the odds ratio. Predicted attributes of the developed scores were then verified using a dataset in 2019.

Results

The incidence of spontaneous rupture was 5.5% from 2002 to 2019. A 10-point score (α-FP of ≥400 µg/L, 1; protrusion from liver surface, 2; ascites, 3; tumor size of >5 cm, 4) was derived for prediction of rupture and area under the receiver-operating characteristic curve was 0.9 (95% confidence interval, 0.87–0.92). When applying a cutoff value of 5 points or more, the specificity was 0.87 and the sensitivity was 0.84. A validation cohort consisting of 202 hepatocellular carcinoma patients reproduces the predictive, identification, and calibration characteristics. The observed rate of spontaneous rupture according to risk stratification of the score was 0.6% for those with a score of 0–4, 21.6% for a score of 5–7, and 36.4% for a score of 8–10 in the validation cohort.

Conclusion

Here, based on routine clinical data, we determine the factors that affect prognosis and propose an effective tool for predicting spontaneous rupture, which may be useful in guiding priority treatment of high-risk patients or clinical routine preventive treatment.

Liver transplantation for hepatocellular carcinoma: Management after the transplant

Hepatocellular carcinoma (HCC) is an increasingly common indication for liver transplantation (LT) in the United States and in many parts of the world. In the last decade, significant work has been done to better understand how to risk stratify LT candidates for recurrence of HCC following transplant using a combination of biomarker and imaging findings. However, despite the high frequency of HCC in the LT population, guidance regarding posttransplant management is lacking. In particular, there is no current evidence to support specific post-LT surveillance strategies, leading to significant heterogeneity in practices. In addition, there are no current recommendations regarding recurrence prevention, including immunosuppression regimen or secondary prevention with adjuvant chemotherapy. Finally, guidance on treatment of disease recurrence is also lacking and there is significant controversy about the use of immunotherapy in transplant recipients due to the risk of rejection. Thus, outcomes for patients with recurrence are poor. This paper therefore provides a comprehensive review of the current literature on post-LT management of patients with HCC and identifies gaps in our current knowledge that are in urgent need of further investigation.

Advances in resection and transplantation for hepatocellular carcinoma

It would be impossible to summarise all of the significant developments in the surgical management of hepatocellular carcinoma (HCC), even just over the past year, in a manuscript of this scope. Thus, we have selected topics for discussion that are the subject of current controversy and have attempted to present balanced points of view. Hepatic resection and transplantation are both mature modalities, and for the most part technical advances and improvements in candidate selection are incremental. The ability to readily cure hepatitis C stands out as the most impactful development in the field over recent years, especially in Western countries where hepatitis C has long been the chief aetiology underlying HCC and a predictor of poor outcomes after surgery, but its full implications remain to be clarified. The rising incidence of non-alcoholic steatohepatitis-related HCC and what it means with regard to surgical HCC management is an area of great current interest. With advancing technology, non-surgical locoregional treatments are gaining increasing application as potentially curative therapies. In addition, the advances in molecular and genomic assessment of HCC hold promise for personalising treatment and prognostication. The possible role of immunotherapy as an adjuvant to resection is being aggressively investigated. While liver surgery maintains an important role, the care of patients with HCC is more and more a team effort and needs to take place in the context of a well-integrated interdisciplinary programme to achieve the best outcomes for patients.