Liver Transplantation and Hepatocellular Carcinoma Biology: Beginning of the End of the Era of Educated Guesses

Krüppel-like Factor 4 Blocks Hepatocellular Carcinoma Dedifferentiation and Progression through Activation of Hepatocyte Nuclear Factor-6

PURPOSE

Tumor differentiation is a behavioral index for hepatocellular carcinoma (HCC) and a prognostic factor for patients with HCC who undergo orthotopic liver transplantation (OLT). However, the molecular basis for HCC differentiation and prognostic value of the underlying molecules that regulate HCC differentiation are unclear. In this study, we defined a potential driver pathway for HCC differentiation and prognostication.

EXPERIMENTAL DESIGN

The regulation and function of Krüppel-like factor 4 (KLF4) and hepatocyte nuclear factor-6 (HNF-6) in HCC differentiation was evaluated using human tissues, molecular and cell biology, and animal models, and its prognostic significance was determined according to its impact on patient survival.

RESULTS

There was a direct relationship between the expression levels of KLF4 and HNF6 in HCC. Reduced KLF4 or HNF6 expression correlated with high HCC grade. Poorly differentiated HCC cells had lower expression of KLF4 or HNF6 and differentiation-associated markers than did well-differentiated cells. Elevated KLF4 of HNF6 expression induced differentiation of poorly differentiated hepatoma cells. Mechanistically, KLF4 trans-activated HNF-6 expression. Restored HNF-6 expression upregulated expression of differentiation-associated markers and inhibited HCC cell migration and invasion, whereas HNF-6 knockdown did the opposite. Loss of KLF4 expression in primary HCC correlated with reduced overall survival and shortened relapse-free survival durations after OLT. Combination of KLF4 expression and the Milan criteria improved prognostication for HCC after OLT.

CONCLUSIONS

The dysregulated KLF4/HNF-6 pathway drives dedifferentition and progression of HCC, and KLF4 is a biomarker for accurate prognostication of patients with HCC treated by OLT when integrated with the Milan Criteria.

Histologic Grade and Mitotic Index as Predictors of Microvascular Invasion in Hepatocellular Carcinoma

OBJECTIVES

Microvascular invasion is a well-known risk factor for hepatocellular carcinoma recurrence and mortality after hepatic resection and liver transplant. We sought to determine the clinico-pathological predictive factors associated with microvascular invasion.

MATERIALS AND METHODS

We studied all patients who had undergone liver transplant because of hepatocellular carcinoma between July 2001 and December 2010 at our institution. Laboratory tests, clinical, and demographic data were obtained. Histopathological hematoxylin and eosin specimens were performed by a single liver pathologist.

RESULTS

During the study, 107 patients had LT because of HCC and they were selected for this investigation: 76 were men (71%) and 31 women (29%) (mean age, 56.8 ± 8.7 y). It was not possible to retrieve histologic samples from 5 patients; therefore, the final studied analysis was 102 individuals. Tumor recurrence rate was 12.9%. One-, three- and five-year overall survivals were 75.0%, 71.4%, and 67.5%. Mitotic index, histologic grade, tumor architecture, alpha-fetoprotein, and tumor fibrosis were associated with microvascular invasion on univariate analysis. Significant independent predictors of microvascular invasion on logistic regression analysis were histologic grade and mitotic index (P < .001; odds ratio, 3.16; 95% confidence interval, 1.525-4.156, and P = .046; odds ratio, 2.56; 95% confidence interval, 1.061-6.451).

CONCLUSIONS

Mitotic index and histologic grade are significant predictors of microvascular invasion. No other risk factor was identified in the logistic regression. As both pathological characteristics may be assessed by liver biopsy, these results highlight the importance of discussing pretransplant liver biopsy to access prognosis and define treatment modalities in the setting of liver transplant.

Liver transplantation in septuagenarians receiving model for end-stage liver disease exception points for hepatocellular carcinoma: the national experience

Current liver allocation policy in the United States grants liver transplant candidates with stage T2 hepatocellular carcinoma (HCC) a priority Model for End-Stage Liver Disease (MELD) score of 22, regardless of age. Because advanced age may portend an increase in all-cause mortality after transplantation for any diagnosis, the aim of this study was to examine overall posttransplant survival in elderly patients with HCC versus younger cohorts. Based on Organ Procurement and Transplantation Network data, Kaplan-Meier 5-year survival rates were compared. Recipients undergoing primary liver transplantation were stratified into cohorts based on age (<70 or ≥ 70 years) and the receipt of MELD exception points for HCC. Log-rank and Wilcoxon tests were used for statistical comparisons. In 2009, 143 transplants were performed for patients who were 70 years old or older. Forty-two percent of these patients received a MELD exception for HCC. Regardless of the diagnosis, the overall survival rate was significantly attenuated for the septuagenarians versus the younger cohort. After 5 years of follow-up, this disparity exceeded 10% to 15% depending on the populations being compared. The 1-, 2-, 3-, 4-, and 5-year actuarial survival rates were 88.4%, 83.2%, 79.6%, 76.1%, and 72.7%, respectively, for the patients who were younger than 70 years and 81.1%, 73.8%, 67.1%, 61.9%, and 55.2%, respectively, for the patients who were 70 years old or older. Five-year survival was negatively affected for patients with HCC who were younger than 70 years; this disparity was not observed for patients with HCC who were 70 years old or older. In conclusion, although patients who are 70 years old or older compose a small fraction of transplant recipients in the United States, patients in this group undergoing transplantation for HCC form an even smaller subset. Overall, transplantation in this age group yields outcomes inferior to those for younger cohorts. However, unlike patients who are less than 70 years old and receive MELD exception points, overall liver transplant survival is not affected by HCC at an advanced age.

Characterization of hepatocellular carcinoma recurrence after liver transplantation: perioperative prognostic factors, patterns, and outcome

OBJECTIVE

Liver transplantation (LT) is known to be a promising treatment for patients with liver cirrhosis associated with hepatocellular carcinoma (HCC). This study, however, found that HCC recurrence remains to be a concern.

METHODS

A total of 126 HCC patients who had undergone LT between January 2000 and December 2009 were retrospectively reviewed. The clinicopathological features of the patients were analyzed by univariate and multivariate analyses to determine prognostic factors. Patients who had HCC recurrence were further analyzed in terms of recurrent pattern, management, and outcome.

RESULTS

Seventeen patients (13.5%) exhibited HCC recurrence following LT. Univariate and multivariate analyses identified two prognostic factors: tumor number > three [hazard ratio (HR) = 3.249] and presence of microvascular invasion (HR = 4.336). Among patients with HCC recurrence, 15 out of 17 (88%) patients developed extrahepatic metastasis shortly after recurrence. The survival of patients after HCC recurrence was dismal with 18.3 months of median survival.

CONCLUSIONS

Multiple tumors (>three) are an important prognostic factor for HCC recurrence following LT, but an accurate assessment of tumor status by pretransplantation radiological examination is required. The outcome of patients with HCC recurrence after LT remains very poor because of a tendency of HCC to recur as extrahepatic metastasis.

Treatment of hepatocellular carcinoma with liver transplantation: a single-center experience from Brazil

INTRODUCTION

Orthotopic liver transplantation (OLT) is the treatment of choice of hepatocellular carcinoma (HCC) for patients with cirrhosis, mainly those with early HCC. Herein we have present the clinical characteristics and outcomes of cirrhotic patients with HCC who underwent OLT from cadaveric donors in our institution.

METHODS

From May 2001 to May 2009, we performed 121 OLT including 24 patients (19.8%) with cirrhosis and HCC within the Milan criteria. In 4 cases, HCC was an incidental finding in the explants.

RESULTS

The patients' average age was 55 +/- 10 years, including 82% men. Fifty percent of patients were Child class B or C. The average Model for End Stage Liver Disease for Child A, B, and C categories were 11, 15, and 18, respectively. The HCC diagnosis was made by 2 dynamic images in 16 cases; 1 dynamic image plus alphafetoprotein >400 ng/mL in 4; and 4 by histologic confirmation. Twenty patients received a locoregional treatment before OLT: 6 percutaneous ethanol injection, 9 transarterial chemoembolization, 1 transarterial embolization, and 4 a combination of these modalities. The median follow-up after OLT was 19.7 months (range, 1-51). A vascular invasion was observed in the explant of 1 patient, who developed an HCC recurrence and succumbed at 8 months after OLT. Two further patients, without vascular invasion or satellite tumor displayed tumor recurrences at 7 and 3 months after OLT, and death at 2 and 1 month after the diagnosis. The remaining 25 patients have not shown a tumor recurrence.

CONCLUSION

In the present evaluation, OLT patients with early HCC and no vascular invasion showed satisfactory results and good disease-free survival. Strictly following the Milan criteria for liver transplantation in patients with HCC greatly reduces but does not completely avoid, the chances of tumor recurrence.

Impact of tumor characteristic on the outcome of liver transplantation in patients with hepatocellular carcinoma

INTRODUCTION

Orthotopic liver transplantation (OLT) is a well-established treatment for cirrhotic patients with hepatocellular carcinoma (HCC) who meet the Milan criteria. The aim of this study was to identify predictors of survival among 65 patients with HCC in cirrhotic livers who underwent liver transplantation (OLT).

METHODS

From January 2001 to December 2008, we performed 655 OLT in 615 patients. HCC was diagnosed in 58 patients before OLT and in 65 by histological examination of the explanted livers; 74% of the patients met Milan criteria by histological examination.

RESULTS

The median follow-up was 27 months (range = 1-96). We analyzed patient age and gender, etiology of liver disease, Child score at transplantation, rejection episodes, tumor number/size, vascular invasion, and differentiation grade. There was no significant difference in survival among patients grouped according to the Model for End-stage Liver Disease staging system for HCC. The 5-year survival of patients with low differentiated (G3) HCC was significantly worse than that of those with moderately differentiated (G2) or well-differentiated (G1) HCC: 50%, 81%, and 86% respectively, (P < .01). Patients with microvascular invasion displayed a worse 5-year survival than those without vascular invasion (42% vs 80%; P < .01).

CONCLUSIONS

The analysis indicated that the histological grade of the tumors and evidences of microscopic vascular invasion were the most useful predictive factors for overall survival among patients with cirrhosis after liver transplantation for HCC.

Liver transplantation for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the commonest primary malignancy of the liver. It usually occurs in the setting of chronic liver disease and has a poor prognosis if untreated. Orthotopic liver transplantation (OLT) is a suitable therapeutic option for early, unresectable HCC particularly in the setting of chronic liver disease. Following on from disappointing initial results, the seminal study by Mazzaferro et al in 1996 established OLT as a viable treatment for HCC. In this study, the “Milan criteria” were applied achieving a 4-year survival rate similar to OLT for benign disease. Since then various groups have attempted to expand these criteria whilst maintaining long term survival rates. The technique of living donor liver transplantation has evolved over the past decade, particularly in Asia, and published outcome data is comparable to that of OLT. This article will review the evidence, indications, and the future direction of liver transplantation for liver cancer.

Tumour size and differentiation in predicting recurrence of hepatocellular carcinoma after liver transplantation: external validation of a new prognostic score

BACKGROUND

A new prognostic score including tumour differentiation--establishing two groups of patients: group A with >3 points and group B with >4 points--improved the accuracy of the Milan criteria in predicting recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) in a large multicentre study (Decaens 2007).

AIM

The aim of this study was to validate the new score in our HCC cohort.

METHODS

The study involved 100 consecutive patients with mean age 55 years (range 31-68 years) (M/F: 88/22) transplanted for known HCC: 60 unifocal and 40 multifocal (2-3 nodules in 32 and >or=4 nodules in 8) at pre-LT imaging. Survival differences were analysed by log-rank test. Patient/tumour variables before LT and tumour differentiation at explant were assessed by univariate/multivariate analysis.

RESULTS

Median follow-up was 29 months (range 1-145 months). HCC recurrence was recorded in 18 patients. Five-year recurrence-free survival rate was 67 +/- 7%. Patient survival at 3 months was 84 +/- 4% and at 5 years was 45 +/- 6%. Both recurrence-free survival and patient survival were not significantly different between groups A and B. Diameter of largest nodule was the sole pre-LT variable independently associated with recurrence [odd ratio (OR) 1.07; 95% confidence interval (CI) 1.01-1.12; P = 0.012]. Recurrence-free survival was significantly better in patients with diameter <30 mm compared with those with larger nodules (P = 0.0229). Number of nodules and tumour differentiation did not influence recurrence. There were three HCC recurrences with largest nodule size <30 mm, seven recurrences between 30-40 mm, and eight recurrences >40 mm.

CONCLUSION

Tumour differentiation did not add significantly to prediction of HCC recurrence in our cohort. Conversely, diameter of the largest nodule remained a significant risk for recurrence.