Intention-to-treat analysis of liver transplantation, resection and thermal ablation for hepatocellular carcinoma in a single centre

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.

Machine Learning Models for Prediction of Posttreatment Recurrence in Early-Stage Hepatocellular Carcinoma Using Pretreatment Clinical and MRI Features: A Proof-of-Concept Study

BACKGROUND. Posttreatment recurrence is an unpredictable complication after liver transplant for hepatocellular carcinoma (HCC) that is associated with poor survival. Biomarkers are needed to estimate recurrence risk before organ allocation. OBJECTIVE. This proof-of-concept study evaluated the use of machine learning (ML) to predict recurrence from pretreatment laboratory, clinical, and MRI data in patients with early-stage HCC initially eligible for liver transplant. METHODS. This retrospective study included 120 patients (88 men, 32 women; median age, 60.0 years) with early-stage HCC diagnosed who were initially eligible for liver transplant and underwent treatment by transplant, resection, or thermal ablation between June 2005 and March 2018. Patients underwent pretreatment MRI and posttreatment imaging surveillance. Imaging features were extracted from postcontrast phases of pretreatment MRI examinations using a pretrained convolutional neural network. Pretreatment clinical characteristics (including laboratory data) and extracted imaging features were integrated to develop three ML models (clinical model, imaging model, combined model) for predicting recurrence within six time frames ranging from 1 through 6 years after treatment. Kaplan-Meier analysis with time to recurrence as the endpoint was used to assess the clinical relevance of model predictions. RESULTS. Tumor recurred in 44 of 120 (36.7%) patients during follow-up. The three models predicted recurrence with AUCs across the six time frames of 0.60-0.78 (clinical model), 0.71-0.85 (imaging model), and 0.62-0.86 (combined model). The mean AUC was higher for the imaging model than the clinical model (0.76 vs 0.68, respectively; p = .03), but the mean AUC was not significantly different between the clinical and combined models or between the imaging and combined models (p > .05). Kaplan-Meier curves were significantly different between patients predicted to be at low risk and those predicted to be at high risk by all three models for the 2-, 3-, 4-, 5-, and 6-year time frames (p < .05). CONCLUSION. The findings suggest that ML-based models can predict recurrence before therapy allocation in patients with early-stage HCC initially eligible for liver transplant. Adding MRI data as model input improved predictive performance over clinical parameters alone. The combined model did not surpass the imaging model's performance. CLINICAL IMPACT. ML-based models applied to currently underutilized imaging features may help design more reliable criteria for organ allocation and liver transplant eligibility.

Management and survival for patients with stage-I hepatocellular carcinoma: An observational study based on SEER database

It is controversial regarding the treatment allocation for patients with stage I hepatocellular carcinoma (SI-HCC). The aim of the present study was to compare the long-term survival in SI-HCC patients undergoing liver transplantation (LT), liver resection (LR), local tumor destruction (LTD), or none. SI-HCC patients diagnosed between 2004 and 2015 were extracted from the SEER 18 registry database. Multivariable Cox models and propensity score matching (PSM) method were used to explore the association between surgical methods and long-term prognosis. A total of 5165 patients with stage I (AJCC, 6th or 7th) HCC were included in the study. Only 36.9% of patients diagnosed with HCC in stage I received surgical therapy. The incidence of LT was decreased over time (P < .001). In the multivariable-adjusted cohort (n = 5165), after adjusting potential confounding factors, a clear prognostic advantage of LT was observed in OS (P < .0001) compared with patients after LR. Patients undergoing LTD had a worse OS in comparison with patients who underwent LR (P < .0001). Patients who received no surgical treatment had the worst OS (P < .0001) among 4 treatment groups. In stratified analyses, the salutary effects of LT vs LR on OS were consistent across all subgroups except for a similar result in the noncirrhotic subgroup (P = .4414). The inferior survival effects of LTD vs LR on OS were consistent across all subgroups, and even in the subgroup with tumor size < 3 cm (P = .0342). In the PSM cohort, patients in LT group showed a better OS (P < .001) than patients in LR group (P < .0001) and patients undergoing LTD had a worse OS compared with patients who underwent LR (P = .00059). In conclusion, LT offered a survival advantage compared with LR among patients with Stage I HCC. LT is the best surgical treatment for stage I HCC in patients with advanced fibrosis, whereas LR provides comparable long-term outcomes to LT in patients without advanced fibrosis and should be considered as the first-line surgical option. LTD can be used as an alternative method when LR and LT are unavailable.