Resection vs Transplant Listing for Hepatocellular Carcinoma: An Intention-to-Treat Analysis

Liver transplantation vs liver resection in HCC: promoting extensive collaborative research through a survival meta-analysis of meta-analyses

Background

HCC is a major global health concern, necessitating effective treatment strategies. This study conducts a meta-analysis of meta-analyses comparing liver resection (LR) and liver transplantation (LT) for HCC.

Methods

The systematic review included meta-analyses comparing liver resection vs. liver transplantation in HCC, following PRISMA guidelines. Primary outcomes included 5-year overall survival (OS) and disease-free survival (DFS). AMSTAR-2 assessed study quality. Citation matrix and hierarchical clustering validated the consistency of the included studies.

Results

A search identified 10 meta-analyses for inclusion. The median Pearson correlation coefficient for citations was 0.59 (IQR 0.41-0.65). LT showed better 5-year survival and disease-free survival in all HCC (OR): 0.79; 95% CI: 0.67-0.93, I^2:57% and OR: 0.44; 95% CI: 0.25-0.75, I^2:96%). Five-year survival in early HCC and ITT was 0.63 (95% CI: 0.50-0.78, I^2:0%) and 0.60 (95% CI: 0.39-0.92, I^2:0%). Salvage LT vs. Primary LT did not differ between 5-year survival and disease-free survival (OR: 0.62; 95% CI: 0.33-1.15, I^2:0% and 0.93; 95% CI: 0.82-1.04, I^2:0%).

Conclusion

Overall, the study underscores the superior survival outcomes associated with LT over LR in HCC treatment, supported by comprehensive meta-analysis and clustering analysis. There was no difference in survival or recurrence rate between salvage LT and primary LT. Therefore, considering the organ shortage, HCC can be resected and transplanted in case of recurrence.

Changes of long-term survival of resection and liver transplantation in hepatocellular carcinoma throughout the years: A meta-analysis

BACKGROUND

Hepatocellular Carcinoma (HCC) still is one of the most detrimental malignant diseases in the world. As two curative surgical therapies exist, the discussion whether to opt for liver resection (LR) or transplantation (LT) is ongoing, especially as novel techniques to improve outcome have emerged for both. The aim of the study was to investigate how the utilization and outcome of the respective modalities changed through time.

METHODS

We searched Medline and PubMed for relevant publications comparing LT and LR in HCC patients during the time period from 1990 to 2022, prior to March 31, 2023. A total of 63 studies involving 19,804 patients - of whom 8178 patients received a liver graft and 11,626 underwent partial hepatectomy - were included in this meta-analysis.

RESULTS

LT is associated with significantly better 5-year overall survival (OS) (64.83%) and recurrence-free survival (RFS) (70.20%) than LR (OS: 50.83%, OR: 1.79, p < 0.001; RFS: 34.46%, OR: 5.32, p < 0.001). However, these differences are not as evident in short-term intervals. Older cohorts showed comparable disparities between the outcome of the respective modalities, as did newer cohorts after 2005. This might be due to the similar improvement in survival rates that were observed for both, LT (15-23%) and LR (12-20%) during the last 30 years.

CONCLUSION

LT still outperforms LR in the therapy of HCC in terms of long-term survival rates. Yet, LR outcome has remarkably improved which is of major importance in reference to the well-known limitations that occur in LT.

Liver resection versus liver transplantation for hepatocellular carcinoma within Milan criteria: a meta-analysis of 18,421 patients

Background

Outcomes after liver resection (LR) and liver transplantation (LT) for hepatocellular carcinoma (HCC) are heterogenous and may vary by region, over time periods and disease burden. We aimed to compare overall survival (OS) and disease-free survival (DFS) between LT versus LR for HCC within the Milan criteria.

Methods

Two authors independently searched Medline and Embase databases for studies comparing survival after LT and LR for patients with HCC meeting the Milan criteria. Meta-analyses and metaregression were conducted using random-effects models.

Results

We screened 2,278 studies and included 35 studies with 18,421 patients. LR was associated with poorer OS [hazard ratio (HR) =1.44; 95% confidence interval (CI): 1.14-1.81; P<0.01] and DFS (HR =2.71; 95% CI: 2.23-3.28; P<0.01) compared to LT, with similar findings among intention-to-treat (ITT) studies. In uninodular disease, OS in LR was comparable to LT (P=0.13) but DFS remained poorer (HR =2.95; 95% CI: 2.30-3.79; P<0.01). By region, LR had poorer OS versus LT in North America and Europe (P≤0.01), but not Asia (P=0.25). LR had inferior survival versus LT in studies completed before 2010 (P=0.01), but not after 2010 (P=0.12). Cohorts that underwent enhanced surveillance had comparable OS after LT and LR (P=0.33), but cohorts undergoing usual surveillance had worse OS after LR (HR =1.95; 95% CI: 1.24-3.07; P<0.01).

Conclusions

Mortality after LR for HCC is nearly 50% higher compared to LT. Survival between LR and LT were similar in uninodular disease. The risk of recurrence after LR is threefold that of LT.

The Treatment Effect of Liver Transplantation versus Liver Resection for HCC: A Review and Future Perspectives

For patients presenting with hepatocellular carcinoma within the Milan criteria, either liver resection or liver transplantation can be performed. However, to what extent either of these treatment options is superior in terms of long-term survival is unknown. Obviously, the comparison of these treatments is complicated by several selection processes. In this article, we comprehensively review the current literature with a focus on factors accounting for selection bias. Thus far, studies that did not perform an intention-to-treat analysis conclude that liver transplantation is superior to liver resection for early-stage hepatocellular carcinoma. In contrast, studies performing an intention-to-treat analysis state that survival is comparable between both modalities. Furthermore, all studies demonstrate that disease-free survival is longer after liver transplantation compared to liver resection. With respect to the latter, implications of recurrences for survival are rarely discussed. Heterogeneous treatment effects and logical inconsistencies indicate that studies with a higher level of evidence are needed to determine if liver transplantation offers a survival benefit over liver resection. However, randomised controlled trials, as the golden standard, are believed to be infeasible. Therefore, we suggest an alternative research design from the causal inference literature. The rationale for a regression discontinuity design that exploits the natural experiment created by the widely adopted Milan criteria will be discussed. In this type of study, the analysis is focused on liver transplantation patients just within the Milan criteria and liver resection patients just outside, hereby ensuring equal distribution of confounders.