Relevance of Preoperative Hyperbilirubinemia in Patients Undergoing Hepatobiliary Resection for Hilar Cholangiocarcinoma

Preoperative hyperbilirubinemia is known to increase the risk of mortality and morbidity in patients undergoing resection for hilar cholangiocarcinoma. The aim of this study was to characterize the associations between the preoperative bilirubin concentration and the risk of postoperative mortality and severe complications to guide decision-making regarding preoperative biliary drainage. Eighty-one patients undergoing liver and bile duct resection for hilar cholangiocarcinoma between 2005 and 2015 were analyzed retrospectively. Postoperative mortality and severe complications, defined as a Clavien⁻Dindo grade of ≥III, were the primary and secondary outcome measures, respectively. The severe postoperative complications and mortality rates were 28.4% (23/81) and 11.1% (9/81), respectively. Patients with preoperative biliary drainage had significantly lower bilirubin concentrations (p = 0.028) than did those without. The preoperative bilirubin concentration was a risk factor of postoperative mortality (p = 0.003), with an optimal cut-off of 6.20 mg/dL (c-statistic = 0.829). The preoperative bilirubin concentration was a risk factor of severe morbidity (p = 0.018), with an optimal cut-off of 2.48 mg/dL (c-statistic = 0.662). These results indicate that preoperative hyperbilirubinemia is a major risk factor of negative early postoperative outcomes of patients who undergo surgical treatment for hilar cholangiocarcinoma and may aid in decision-making with respect to preoperative biliary drainage.

Individual Surgeon Experience Yields Bimodal Effects on Patient Outcomes After Deceased-Donor Liver Transplant: Results of a Quantile Regression for Survival Data

OBJECTIVES

Data on the relevance of surgeon experience in liver transplant procedures are scarce. In this study, we evaluated the effects of individual surgeon experience on survival outcomes after deceased-donor liver transplant.

MATERIALS AND METHODS

In this retrospective analysis of 1193 liver transplant procedures, quantile regression for survival data was performed to assess the effects of surgeon experience. Conditional quantiles of mortality and graft loss were set as primary and secondary outcome measures, respectively, which were categorized as early, midterm, and late.

RESULTS

Greater experience of a surgeon performing hepatectomy increased the risk of early mortality (P = .005) and graft loss (P = .025) when the recipient Model for End-Stage Liver Disease was ≤ 25 and the donor Model for End-Stage Liver Disease was ≤ 1600. In conventional transplant procedures, greater experience of surgeon performing hepatectomy additionally increased the risk of midterm mortality (P = .027) and graft loss (P = .046). Conversely, a graft implant procedure performed by a more experienced surgeon was associated with better early, midterm, and late outcomes after conventional transplants (all P < .037) and reduced the risk of early graft loss when the donor Model for End-Stage Liver Disease score was > 1600 (P = .027).

CONCLUSIONS

Unexpectedly, individual surgeon experience yields bimodal effects on posttransplant outcomes, dependent on the stage of operation, operative technique, severity of recipient status, and transplant risk profile.

Profile of Gut Microbiota Associated With the Presence of Hepatocellular Cancer in Patients With Liver Cirrhosis

BACKGROUND

Changes within the gut microbiota contribute to the progression of chronic liver diseases. According to the results of several studies performed in animal models, gut dysbiosis plays an important role in hepatocarcinogenesis. The aim of this study was to explore the characteristics of gut microbiota associated with the presence of hepatocellular cancer (HCC) in patients with cirrhosis of the liver undergoing liver transplantation.

METHODS

A total of 15 patients with HCC and 15 non-HCC patients matched according to etiology of cirrhosis and Model for End-Stage Liver Disease (MELD) scores who underwent liver transplantations between 2012 and 2014 were included. Analysis of their gut microbial profile was based on prospectively collected stool samples from the pretransplant period.

RESULTS

Patients with and without HCC were similar with respect to age (P = .506), sex (P = .700), hepatitis C virus (P > .999) and hepatitis B virus (P = .715) infection status, alcoholic liver disease (P > .999), and MELD score (P = .337). Notably, the presence of HCC was associated with significantly increased fecal counts of Escherichia coli (P = .025). Prediction of HCC presence based on E coli counts was associated with the area under the receiver-operating curve of 0.742 (95% confidence interval, 0.564-0.920), with the optimal cutoff on the level of 17.728 (natural logarithm of colony-forming units per 1 g of feces). Sensitivity and specificity rates for the established cutoff were 66.7% and 73.3%, respectively.

CONCLUSIONS

The profile of gut microbiota associated with the presence of HCC in cirrhotic patients is characterized by increased fecal counts of E coli. Therefore, intestinal overgrowth of E coli may contribute to the process of hepatocarcinogenesis.

Liver Transplantation Outcomes in Recipients with High Model for End-Stage Liver Disease (MELD) Scores: The Relevance of MELD Scores

BACKGROUND The aim of this study was to assess risk factors for postoperative mortality after liver transplantation among patients with Model for End-Stage Liver Disease (MELD) scores ≥35, with special focus on the MELD scores. MATERIAL AND METHODS Data from 68 primary liver transplantations in patients with MELD scores ≥35 among 1376 liver transplantations performed in the Department of General, Transplant, and Liver Surgery (Medical University of Warsaw) between January 2002 and October 2014 were analyzed retrospectively. Postoperative (90-day) mortality was set as the primary outcome measure. RESULTS Postoperative mortality was 29.4% (20 of 68). The overall survival rates after 1, 5, and 10 years were 61.9%, 59.7%, and 59.7%, respectively. According to univariate analyses, MELD (p=0.014), conventional technique of liver transplantation (p=0.049), intraoperative fresh frozen plasma (p=0.040), and red blood cells (p=0.026) transfusions were risk factors for postoperative mortality. MELD score was the only independent risk factor for postoperative mortality (p=0.023) in multivariate analysis. According to receiver operating characteristics analysis, the optimal cut-off for MELD score in prediction of postoperative mortality was ≥43 (Area Under Curve=0.703, 95% Confidence Interval 0.575-0.831). Postoperative mortality was 21.4% and 42.3% among patients with MELD score <43 and ≥43, respectively (p=0.066). CONCLUSIONS MELD score is an important predictor of early mortality after liver transplantation, even among recipients with high MELD scores. In particular, patients with MELD score ≥43 should be considered as very high-risk candidates for liver transplantation.

Comparison of Total Tumor Volume, Size and Number of Colorectal Liver Metastases in Prediction of Survival in Patients after Liver Resection

Liver is the most common location of the colorectal cancer metastases occurrence. Liver resection is the only curative method of treatment. Unfortunately it is feasible only in 25% of patients with colorectal liver metastases, often because of the extensiveness of the disease. The aim of the study was to evaluate the predictive value of total tumor volume, size and number of colorectal liver metastases in patients treated with right hemihepatectomy.

MATERIAL AND METHODS

A retrospective analysis was performed in a group of 135 patients with colorectal liver metastases, who were treated with right hemihepatectomy. Total tumor volume was estimated based on the formula (4/3)πr³. Moreover, the study included an analysis of data on the number and size of tumors, radicality of the resection, time between primary tumor resection and liver resection, pre-operative blood serum concentration of carcinoembryonal antigen (CEA) and carcinoma antigen Ca 19-9. The predictive value of the factors was evaluated by applying a Cox proportional hazards model and the area under the ROC curve.

RESULTS

The univariate analysis has shown the predictive value of size of the largest tumor (p=0.033; HR=1.065 per each cm) on the overall survival, however no predictive value of number of tumors (p=0.997; HR=1.000) and total tumor volume (p=0.212; HR=1.002) was observed. The multivariate analysis did not confirm the predictive value of the size of the largest tumor (p=0.141; HR=1.056). In the analysis of ROC curves, AUROC for the total tumor volume, the size of the largest tumor and the number of tumors were 0.629, 0.608, 0.520, respectively.

CONCLUSIONS

Total tumor volume, size and number of liver metastases are not independent risk factors for the worse overall survival of patients with colorectal liver metastases treated with liver resection, therefore increased values of these factors should not be a contraindication for surgical treatment.

Outcomes of Patients With Poorly Differentiated Hepatocellular Carcinoma After Liver Transplantation

BACKGROUND

Liver transplantation (LT) outcomes for patients with poorly differentiated (G3) hepatocellular carcinoma (HCC) are unsatisfactory. The aim of this study was to evaluate outcomes in patients with poorly differentiated HCC undergoing LT.

PATIENTS AND METHODS

There were 192 HCC patients after LT in the Department of General, Transplant and Liver Surgery, Medical University of Warsaw, between January 2001 and April 2014. The study group comprised 24 patients with poorly differentiated tumors.

RESULTS

Disease-free survival (DFS) for all patients was 49.5% at 5 years. The 5-year DFS for patients who met the Milan criteria (n = 9, 88.9%) was significantly better compared to those who did not (n = 15, 28.0%, P = .025). Multivariable analysis revealed that only the largest tumor diameter (P = .014) and α-fetoprotein (AFP) concentration (P = .001) were independent risk factors for DFS. The optimal cut-off AFP and tumor size that could distinguish patients with the highest risk were ≥500 ng/mL and ≥3.5 cm, respectively. DFS for patients with AFP <500 ng/mL and tumor size <3.5 cm was 100% after 2.8 years, and for those with ≥500 ng/mL or tumor size ≥3.5 cm was 46.9% after 5 years. However, the DFS for patients with AFP ≥500 ng/mL and tumor size ≥3.5 cm was only 12.5% after 4.7 years (P = .002).

CONCLUSIONS

Outcomes of patients with poorly differentiated HCC treated with LT can be characterized with acceptable survival when applying criteria based on tumor size <3.5 cm and AFP <500 ng/mL.

Relevance of Pre-Transplant α-fetoprotein Dynamics in Liver Transplantation for Hepatocellular Cancer

BACKGROUND

The magnitude of pre-transplant a-fetoprotein (AFP) changes has been advocated to be a superior predictor of hepatocellular cancer (HCC) recurrence following liver transplantation. The aim of this study was to compare AFP dynamics and last pre-transplant AFP as risk factors for post-transplant HCC recurrence.

MATERIAL AND METHODS

Data of 146 patients after liver transplantation for HCC were analyzed retrospectively.

RESULTS

While last pre-transplant AFP was a significant predictor of microvascular invasion (p=0.006) and poor tumor differentiation (p=0.020), AFP slope was associated only with microvascular invasion (p=0.029). Notably, last pre-transplant AFP (p<0.001), but not AFP slope (p=0.279), was an independent risk factor for recurrence. No significant effects of AFP slope were also found following division of patients into those with pre-transplant AFP <100 (p=0.260) and those with AFP >100 (p=0.178) ng/mL. Moreover, prediction of recurrence based on last pre-transplant AFP was superior (p=0.018) to those based on AFP slope. Recurrence-free survival at 5 years was superior in patients with pre-transplant AFP persistently at (97.3%) or dropping to <100 ng/mL (100.0%) as compared to patients with AFP rising to (75.0%) or persistently at >100 ng/mL (38.4%; p<0.001).

CONCLUSIONS

The risk of post-transplant HCC recurrence is dependent on the last pre-transplant AFP regardless of its previous dynamics.

Relevance of male-to-female sex mismatch in liver transplantation for primary biliary cirrhosis

BACKGROUND

Because male-to-female transplantations are related to exposure to H-Y antigen, sex matching may influence the outcomes after liver transplantation for autoimmune diseases. The purpose of this retrospective study was to evaluate the relevance of male-to-female mismatch in liver transplantation for primary biliary cirrhosis (PBC).

MATERIAL AND METHODS

This retrospective study was based on the data of 82 female liver transplant recipients with PBC from a single institution. The primary outcome measure was graft survival at 10 years. The negative effects of well-known risk factors for poor outcomes were evaluated separately and compared between the female-to-female and male-to-female transplantations.

RESULTS

Graft survival was similar after female-to-female and male-to-female transplantations (74.7% versus 73.1% at 10 years, respectively, p=0.676). Regarding the differential impact of other risk factors, prolonged cold ischemia and increased amount of blood transfusions adversely influenced outcomes after male-to-female transplantation (p=0.039 and p=0.039, respectively) but not after female-to-female transplantation (p=0.843 and p=0.110, respectively). Sex mismatched transplantations were associated with lower 10-year graft survival in subgroups of patients with blood transfusions >4 units (61.4% versus 100.0%, p=0.063) and >8 hours of cold ischemia (54.7% versus 75.8%, p=0.418).

CONCLUSIONS

Although male-to-female sex mismatch does not seem to yield a direct negative impact on outcomes following liver transplantation for PBC, it can aggravate the negative effects of prolonged cold ischemia and blood transfusions.

The relevance of intestinal dysbiosis in liver transplant candidates

BACKGROUND

The gut microbial ecosystem plays an important role in the pathogenesis of liver diseases. However, the association of microbial community structure with the severity of liver dysfunction is not completely understood.

METHODS

Fecal microflora was assessed in 40 patients with liver cirrhosis listed for primary liver transplantation (LT). Independent associations between fecal microbial counts and serum bilirubin, serum creatinine, international normalized ratio (INR), and the Model for End-stage Liver Disease (MELD) score were established in multiple linear regression models.

RESULTS

Bifidobacterium (standardized regression coefficient [sβ] = -0.549; P < 0.001), Enterococcus (sβ = 0.369; P = 0.004), and yeast (sβ = 0.315; P = 0.018) numbers were independently associated with serum bilirubin, while Escherichia coli counts (sβ = 0.318; P = 0.046) correlated with INR, and Bifidobacterium counts (sβ = 0.410; P = 0.009) with serum creatinine. Only Bifidobacterium (sβ = -0.468; P = 0.003) and Enterococcus (sβ = 0.331; P = 0.029) counts were independent predictors of the MELD score. Bifidobacterium/Enterococcus ratio, proposed as a measure of pre-LT gut dysbiosis, was significantly related to the MELD score following the adjustment for the absolute Bifidobacterium (sβ = -0.333; P = 0.029) and Enterococcus (sβ = -0.966; P = 0.003) numbers. This pre-transplant dysbiosis ratio (PTDR) was significantly correlated with Enterococcus (R = -0.897; P < 0.001) but not with Bifidobacterium (R = 0.098; P = 0.546) counts. Among the other components of gut microflora, only hydrogen peroxide (H2 O2 )-producing Lactobacillus strains significantly influenced Enterococcus counts (sβ = 0.349; P = 0.028) and PTDR (sβ = -0.318; P = 0.046).

CONCLUSION

While the abundance of both Bifidobacterium and Enterococcus is related to liver dysfunction, the size of the Enterococcus population seems to be the most important determinant of pre-LT gut dysbiosis in cirrhotic patients. The H2 O2 -producing Lactobacillus strains potentially ameliorate this dysbiotic state.

Negative outcomes after liver transplantation in patients with alcoholic liver disease beyond the fifth post-transplant year

Although up to 50% of patients with alcoholic liver disease (ALD) resume alcohol consumption after liver transplantation (LT), numerous studies indicate that long-term results are not compromised. This study focused on evaluating the impact of ALD on outcomes up to and beyond the fifth year after LT. Among the 432 primary LT recipients included in this study, 97 underwent transplantation for ALD. Alcohol relapse rate at 10 yr was 33.5%, with younger recipient age being the only independent predictor (p = 0.019). Survival of patients with ALD (77.0%) was similar to those without (79.0%) up to the fifth post-transplant year (p = 0.655) but worse during the five subsequent years among the five-yr survivors (70.6% vs. 92.9%; p = 0.002). ALD was an independent risk factor for poorer survival beyond the fifth post-transplant year (p = 0.049), but not earlier (p = 0.717). Conversely, alcohol relapse increased the risk of death only during the first five post-transplant years (p = 0.039). There were no significant differences regarding graft failure incidence between ALD and non-ALD recipients up to the fifth post-transplant year (7.3% vs. 11.6%; p = 0.255) and beyond (12.9% vs. 5.0%; p = 0.126). In conclusion, pre-transplant diagnosis of ALD yields negative effects on post-transplant outcomes beyond the fifth post-transplant year, not attributable to recidivism.

Post-transplant outcomes of patients with and without hepatitis C virus infection according to donor age and gender matching

BACKGROUND

The purpose of this study was to evaluate the impact of donor age and donor-recipient gender matching on liver transplantation outcomes, focusing on differences between patients with and without hepatitis C virus (HCV) infection.

MATERIAL AND METHODS

This retrospective cohort study evaluated 622 liver transplantation recipients. HCV (n=164) and non-HCV (n=458) patients were subdivided by donor age (≤ 30, 31-50, and >50 years) and donor-recipient gender configurations. Five-year patient survival (PS) and graft survival (GS) were set as outcome measures.

RESULTS

Five-year PS was 83.1% for HCV-positive and 81.6% for HCV-negative patients (p=0.614), with the corresponding GS rates of 81.2% and 79.3% (p=0.538), respectively. In HCV patients, transplantations from donors older than 50 years were associated with lower PS (p=0.035) and GS (p=0.006) than those from donors aged 31-50 years. This difference was not observed among non-HCV recipients (PS, p=0.994; GS, p=0.878). Regarding donor-recipient gender configurations, outcomes were similar in HCV (PS, p=0.751; GS, p=0.592) and non-HCV patients (PS, p=0.217; GS, p=0.249), except for a tendency toward lower PS for male-to-female transplantations than female-to-female transplantations in non-HCV patients (p=0.064). Outcomes of HCV patients were superior to those of non-HCV patients after transplantation from donors aged 31-50 years (PS, p=0.080; GS, p=0.026).

CONCLUSIONS

Avoiding the transplantation of grafts from donors aged over 50 years to patients with HCV infection might improve the general outcomes of liver transplantation programs. There is no specific rationale for gender matching with respect to HCV status.