Endothelium-coated tumor clusters are associated with poor prognosis and micrometastasis of hepatocellular carcinoma after resection

Optimizing predictions: improved performance of preoperative gadobenate-enhanced MRI hepatobiliary phase features in predicting vessels encapsulating tumor clusters in hepatocellular carcinoma-a multicenter study

BACKGROUND

Vessels Encapsulating Tumor Clusters (VETC) are now recognized as independent indicators of recurrence and overall survival in hepatocellular carcinoma (HCC) patients. However, there has been limited investigation into predicting the VETC pattern using hepatobiliary phase (HBP) features from preoperative gadobenate-enhanced MRI.

METHODS

This study involved 252 HCC patients with confirmed VETC status from three different hospitals (Hospital 1: training set with 142 patients; Hospital 2: test set with 64 patients; Hospital 3: validation set with 46 patients). Independent predictive factors for VETC status were determined through univariate and multivariate logistic analyses. Subsequently, these factors were used to construct two distinct VETC prediction models. Model 1 included all independent predictive factors, while Model 2 excluded HBP features. The performance of both models was assessed using the Area Under the Curve (AUC), Decision Curve Analysis, and Calibration Curve. Prediction accuracy between the two models was compared using Net Reclassification Improvement (NRI) and Integrated Discriminant Improvement (IDI).

RESULTS

CA199, IBIL, shape, peritumoral hyperintensity on HBP, and arterial peritumoral enhancement were independent predictors of VETC. Model 1 showed robust predictive performance, with AUCs of 0.836 (training), 0.811 (test), and 0.802 (validation). Model 2 exhibited moderate performance, with AUCs of 0.813, 0.773, and 0.783 in the respective sets. Calibration and decision curves for both models indicated consistent predictions between predicted and actual VETC, benefiting HCC patients. NRI showed Model 1 increased by 0.326, 0.389, and 0.478 in the training, test, and validation sets compared to Model 2. IDI indicated Model 1 increased by 0.036, 0.028, and 0.025 in the training, test, and validation sets compared to Model 2.

CONCLUSION

HBP features from preoperative gadobenate-enhanced MRI can enhance the predictive performance of VETC in HCC.

The prognostic value of vessels encapsulating tumor clusters (VETC) in patients with hepatocellular carcinoma: a systematic review and meta-analysis

BACKGROUND

Studies have suggested that vessels encapsulating tumor clusters (VETC) is a strong predictor of prognosis in patients with hepatocellular carcinoma (HCC).

METHODS

A systematic search was conducted in PubMed, Embase, Web of Science, and Scopus databases. Overall survival (OS) and tumor efficacy (TE) were two outcome measures used to evaluate the relationship between VETC and HCC prognosis. Hazard ratios (HR) and their 95% confidence intervals (CI) were used.

RESULTS

Thirteen studies with 4429 patients were included in the meta-analysis. The results showed that VETC was significantly associated with both OS (HR 2.00; 95% CI 1.64-2.45) and TE (HR 1.70; 95% CI 1.44-1.99) in HCC patients. Furthermore, recurrence-free survival (RFS) was a stronger indicator of tumor efficacy (HR 1.73; 95% CI 1.44-2.07) than disease-free survival (DFS) (HR 1.69; 95% CI 1.22-2.35). This suggests that VETC-positive HCC has a higher risk of recurrence and a lower survival rate.

CONCLUSION

In conclusion, the meta-analysis suggests that VETC is a significant predictor of overall survival and tumor efficacy in HCC patients and may be a valid prognostic indicator.

Histological predictors of aggressive recurrence of hepatocellular carcinoma after liver resection

BACKGROUND & AIMS

Assessment of recurrence risk after liver resection (LR) is critical in hepatocellular carcinoma (HCC), particularly with the advent of effective adjuvant therapy. The aim of this study was to analyze the clinical and pathological factors associated with recurrence, aggressive recurrence, and survival after LR.

METHOD

We performed a retrospective study in which all single HCC (BCLC-0/A) patients treated with LR between February 2000 and November 2020 were included. The main clinical variables were recorded. Histological features were blindly evaluated by two independent pathologists. Aggressive recurrence was defined as those that exceeded the Milan criteria at 1st recurrence.

RESULTS

A total of 218 patients were included (30% BCLC 0 and 70% BCLC A), median (IQR) tumor size of 28 (19-42 mm). The prevalence of microvascular invasion and/or satellitosis (mVI/S) was 39%, with a kappa-index between both pathologists of 0.8. After a median follow-up of 49 (23-85) months, 61/218 (28%) patients died, 32/218 (15%) underwent liver transplantation, 127 (58%) developed HCC recurrence. The prevalence of aggressive recurrence was 35% (44/127 Milan-out, with 20 cases at advanced stage), and the 5-year survival rate was 81%. The presence of mVI/S was the only independent predictor of recurrence (hazard ratio [HR] 1.83, 95% CI 1.28-2.61, p <0.001), aggressive recurrence (HR 3.31, 95% CI 1.74-6.29, p <0.001) and mortality (HR 2.23, 95% CI 1.27-3.91, p = 0.005). The macrotrabecular-massive subtype was significantly associated with a higher prevalence of mVI/S, Edmonson Steiner grade III-IV, AFP values and vessels that encapsulate tumor clusters, but not with recurrence, aggressive recurrence, or overall survival.

CONCLUSION

The presence of mVI/S was the only independent risk factor for aggressive recurrence and mortality. This has important implications for early-stage patient management, especially in the setting of adjuvant immunotherapy or ab initio LT.

IMPACT AND IMPLICATIONS

Assessment of recurrence risk after liver resection is crucial in patients with hepatocellular carcinoma. Patients with a high risk of recurrence are candidates for liver transplantation as an ab initio indication or for the potential use of adjuvant therapy. Aggressive recurrences, defined as those exceeding the Milan criteria at first recurrence, have a significant impact on overall survival (OS). Fifty-eight percent of patients experienced hepatocellular carcinoma recurrence, with a prevalence of aggressive recurrence at the first occurrence standing at 35%. After a median follow-up of 49 (23-85) months, 61 (28%) patients died, and 32 (15%) underwent liver transplantation, resulting in a 5-year OS rate of 81%. Microvascular invasion and/or satellitosis was present in 39% of our cohort and was the only independent predictor of recurrence, aggressive recurrence, and OS on multivariate analysis. This is important as it could be used to guide therapeutic management.

Nomogram prediction of vessels encapsulating tumor clusters in small hepatocellular carcinoma ≤ 3 cm based on enhanced magnetic resonance imaging

BACKGROUND

Vessels encapsulating tumor clusters (VETC) represent a recently discovered vascular pattern associated with novel metastasis mechanisms in hepatocellular carcinoma (HCC). However, it seems that no one have focused on predicting VETC status in small HCC (sHCC). This study aimed to develop a new nomogram for predicting VETC positivity using preoperative clinical data and image features in sHCC (≤ 3 cm) patients.

AIM

To construct a nomogram that combines preoperative clinical parameters and image features to predict patterns of VETC and evaluate the prognosis of sHCC patients.

METHODS

A total of 309 patients with sHCC, who underwent segmental resection and had their VETC status confirmed, were included in the study. These patients were recruited from three different hospitals: Hospital 1 contributed 177 patients for the training set, Hospital 2 provided 78 patients for the test set, and Hospital 3 provided 54 patients for the validation set. Independent predictors of VETC were identified through univariate and multivariate logistic analyses. These independent predictors were then used to construct a VETC prediction model for sHCC. The model's performance was evaluated using the area under the curve (AUC), calibration curve, and clinical decision curve. Additionally, Kaplan-Meier survival analysis was performed to confirm whether the predicted VETC status by the model is associated with early recurrence, just as it is with the actual VETC status and early recurrence.

RESULTS

Alpha-fetoprotein_lg10, carbohydrate antigen 199, irregular shape, non-smooth margin, and arterial peritumoral enhancement were identified as independent predictors of VETC. The model incorporating these predictors demonstrated strong predictive performance. The AUC was 0.811 for the training set, 0.800 for the test set, and 0.791 for the validation set. The calibration curve indicated that the predicted probability was consistent with the actual VETC status in all three sets. Furthermore, the decision curve analysis demonstrated the clinical benefits of our model for patients with sHCC. Finally, early recurrence was more likely to occur in the VETC-positive group compared to the VETC-negative group, regardless of whether considering the actual or predicted VETC status.

CONCLUSION

Our novel prediction model demonstrates strong performance in predicting VETC positivity in sHCC (≤ 3 cm) patients, and it holds potential for predicting early recurrence. This model equips clinicians with valuable information to make informed clinical treatment decisions.

A deep learning model based on MRI for prediction of vessels encapsulating tumour clusters and prognosis in hepatocellular carcinoma

PURPOSE

This study aimed to build and evaluate a deep learning (DL) model to predict vessels encapsulating tumor clusters (VETC) and prognosis preoperatively in patients with hepatocellular carcinoma (HCC).

METHODS

320 pathologically confirmed HCC patients (58 women and 262 men) from two hospitals were included in this retrospective study. Institution 1 (n = 219) and Institution 2 (n = 101) served as the training and external test cohorts, respectively. Tumors were evaluated three-dimensionally and regions of interest were segmented manually in the arterial, portal venous, and delayed phases (AP, PP, and DP). Three ResNet-34 DL models were developed, consisting of three models based on a single sequence. The fusion model was developed by inputting the prediction probability of the output from the three single-sequence models into logistic regression. The area under the receiver operating characteristic curve (AUC) was used to compare performance, and the Delong test was used to compare AUCs. Early recurrence (ER) was defined as recurrence within two years of surgery and early recurrence-free survival (ERFS) rate was evaluated by Kaplan-Meier survival analysis.

RESULTS

Among the 320 HCC patients, 227 were VETC- and 93 were VETC+ . In the external test cohort, the fusion model showed an AUC of 0.772, a sensitivity of 0.80, and a specificity of 0.61. The fusion model-based prediction of VETC high-risk and low-risk categories exhibits a significant difference in ERFS rates, akin to the outcomes observed in VETC + and VETC- confirmed through pathological analyses (p < 0.05).

CONCLUSIONS

A DL framework based on ResNet-34 has demonstrated potential in facilitating non-invasive prediction of VETC as well as patient prognosis.

Potential involvement of oncostatin M in the immunosuppressive tumor immune microenvironment in hepatocellular carcinoma with vessels encapsulating tumor clusters

AIM

Vessels encapsulating tumor clusters (VETC) represents an adverse prognostic morphological feature of hepatocellular carcinoma (HCC), which is associated with an immunosuppressive tumor immune microenvironment (TIM). However, the underlying factors characterizing the TIM in HCC with a VETC pattern (VETC-positive HCC) remain uncertain. Oncostatin M (OSM), a pleiotropic cytokine of the interleukin-6 family, regulates various biological processes, including inflammation, proliferation, and invasiveness of tumor cells. We aimed to test a hypothesis that OSM is associated with the immunosuppressive TIM of VETC-positive HCC.

METHODS

A total of 397 consecutive HCC patients with curative-intent hepatectomy were included. OSM-positive cells and inflammatory cells including CD4-, CD8-, CD163-, and FOXP3-positive cells were immunohistochemically evaluated. We compared VETC-positive and VETC-negative HCCs in terms of the number of these cells.

RESULTS

We found the VETC pattern in 62 patients (15.6%). Our analysis revealed a significant decrease in the expression of arginase-1, a marker associated with mature hepatocyte differentiation, in VETC-positive HCC (p = 0.046). The number of tumor-infiltrating OSM-positive cells was significantly low in VETC-positive HCC (p = 0.0057). Notably, in VETC-positive HCC, the number of OSM-positive cells was not associated with vascular invasion, whereas in VETC-negative HCC, an increase in the number of OSM-positive cells was associated with vascular invasion (p = 0.042).

CONCLUSIONS

We identified an association between a decrease in OSM-positive cells and the VETC pattern. Additionally, our findings indicate that VETC-positive HCC is characterized by low hepatocyte differentiation and OSM-independent vascular invasion. These findings highlight the potential interaction between VETC-positive HCC cells and their TIM through the reduction of OSM-expressing cells.

Preoperatively predicting vessels encapsulating tumor clusters in hepatocellular carcinoma: Machine learning model based on contrast-enhanced computed tomography

BACKGROUND

Recently, vessels encapsulating tumor clusters (VETC) was considered as a distinct pattern of tumor vascularization which can primarily facilitate the entry of the whole tumor cluster into the bloodstream in an invasion independent manner, and was regarded as an independent risk factor for poor prognosis in hepatocellular carcinoma (HCC).

AIM

To develop and validate a preoperative nomogram using contrast-enhanced computed tomography (CECT) to predict the presence of VETC+ in HCC.

METHODS

We retrospectively evaluated 190 patients with pathologically confirmed HCC who underwent CECT scanning and immunochemical staining for cluster of differentiation 34 at two medical centers. Radiomics analysis was conducted on intratumoral and peritumoral regions in the portal vein phase. Radiomics features, essential for identifying VETC+ HCC, were extracted and utilized to develop a radiomics model using machine learning algorithms in the training set. The model's performance was validated on two separate test sets. Receiver operating characteristic (ROC) analysis was employed to compare the identified performance of three models in predicting the VETC status of HCC on both training and test sets. The most predictive model was then used to constructed a radiomics nomogram that integrated the independent clinical-radiological features. ROC and decision curve analysis were used to assess the performance characteristics of the clinical-radiological features, the radiomics features and the radiomics nomogram.

RESULTS

The study included 190 individuals from two independent centers, with the majority being male (81%) and a median age of 57 years (interquartile range: 51-66). The area under the curve (AUC) for the combined radiomics features selected from the intratumoral and peritumoral areas were 0.825, 0.788, and 0.680 in the training set and the two test sets. A total of 13 features were selected to construct the Rad-score. The nomogram, combining clinical-radiological and combined radiomics features could accurately predict VETC+ in all three sets, with AUC values of 0.859, 0.848 and 0.757. Decision curve analysis revealed that the radiomics nomogram was more clinically useful than both the clinical-radiological feature and the combined radiomics models.

CONCLUSION

This study demonstrates the potential utility of a CECT-based radiomics nomogram, incorporating clinical-radiological features and combined radiomics features, in the identification of VETC+ HCC.

Recurrence-free Survival After Liver Transplantation Versus Surgical Resection for Hepatocellular Carcinoma: Role of High-risk MRI Features

BACKGROUND

This study aimed to evaluate recurrence-free survival (RFS) and overall survival (OS) after liver transplantation (LT) or liver resection (LR) for hepatocellular carcinoma (HCC) and perform subgroup analysis for HCC with high-risk imaging findings for recurrence on preoperative liver magnetic resonance imaging (MRI; high-risk MRI features).

METHODS

We included patients with HCC eligible for both LT and LR and received either of the treatments between June 2008 and February 2021 from 2 tertiary referral medical centers after propensity score-matching. RFS and OS were compared between LT and LR using Kaplan-Meier curves with the log-rank test.

RESULTS

Propensity score-matching yielded 79 patients in the LT group and 142 patients in the LR group. High-risk MRI features were noted in 39 patients (49.4%) in the LT group and 98 (69.0%) in the LR group. The Kaplan-Meier curves for RFS and OS were not significantly different between the 2 treatments among the high-risk group (RFS, P  = 0.079; OS, P  = 0.755). Multivariable analysis showed that treatment type was not a prognostic factor for RFS and OS ( P  = 0.074 and 0.937, respectively).

CONCLUSIONS

The advantage of LT over LR for RFS may be less evident among patients with high-risk MRI features.

Vessels encapsulating tumor clusters: a novel efficacy predictor of hepatic arterial infusion chemotherapy in unresectable hepatocellular carcinoma

PURPOSE

Vessels encapsulating tumor clusters (VETC) is a novel vascular pattern structurally and functionally distinct from microvascular invasion (MVI) in hepatocellular carcinoma (HCC). This study aims to explore the prognostic value of VETC in patients receiving hepatic arterial infusion chemotherapy (HAIC) for unresectable HCC.

METHODS

From January 2016 to December 2017, 145 patients receiving HAIC as the initial treatment for unresectable HCC were enrolled and stratified into two groups according to their VETC status. Overall survival (OS), progression-free survival (PFS), overall response rate (ORR), and disease control rate (DCR) were evaluated.

RESULTS

The patients were divided into two groups: VETC+ (n = 31, 21.8%) and VETC- (n = 114, 78.2%). The patients in the VETC+ group had worse ORR and DCR than those in the VETC- group (RECIST: ORR: 25.8% vs. 47.4%, P = 0.031; DCR: 56.1% vs. 76.3%, P = 0.007; mRECIST: ORR: 41.0% vs. 52.6%, P = 0.008; DCR: 56.1% vs. 76.3%, P = 0.007). Patients with VETC+ had significantly shorter OS and PFS than those with VETC- (median OS: 10.2 vs. 21.6 months, P < 0.001; median PFS: 3.3 vs. 7.2 months, P < 0.001). Multivariate analysis revealed VETC status as an independent prognostic factor for OS (HR: 2.40; 95% CI: 1.46-3.94; P = 0.001) and PFS (HR: 1.97; 95% CI: 1.20-3.22; P = 0.007).

CONCLUSION

VETC status correlates remarkably well with the tumor response and long-term survival in patients undergoing HAIC. It may be a promising efficacy predictor and help identify patients who will benefit from HAIC.

Vessels that encapsulate tumour clusters vascular pattern in hepatocellular carcinoma

Vessels that encapsulate tumour clusters (VETC) is a distinct histologic vascular pattern associated with a novel mechanism of metastasis. First described in human cancers in 2004, its prevalence and prognostic significance in hepatocellular carcinoma (HCC) has only been appreciated in the past decade with a rapidly increasing body of literature. A robust biomarker of aggressive disease, the VETC pattern is easy to recognise but relies on histologic examination of tumour tissue for its diagnosis. Radiological recognition of the VETC pattern is an area of active research and is becoming increasingly accurate. As a prognostic marker, VETC has consistently proven to be an independent predictor of disease recurrence and overall survival in patients with HCC undergoing resection and liver transplantation. It can also guide treatment by predicting response to other therapies such as transarterial chemoembolisation and sorafenib. Without prospective randomised-controlled trials or routine evaluation of VETC in clinical practice, there are currently no firm treatment recommendations for VETC-positive tumours, although some perspectives are provided in this review based on the latest knowledge of their pathogenesis - a complex interplay between tumour angiogenesis and the immune microenvironment. Nevertheless, VETC has great potential as a future biomarker that could take us one step closer to precision medicine for HCC.

Preoperative prediction of VETC in hepatocellular carcinoma using non-Gaussian diffusion-weighted imaging at high b values: a pilot study

Background

Vessels encapsulating tumor clusters (VETC) have been considered an important cause of hepatocellular carcinoma (HCC) metastasis.

Purpose

To compare the potential of various diffusion parameters derived from the monoexponential model and four non-Gaussian models (DKI, SEM, FROC, and CTRW) in preoperatively predicting the VETC of HCC.

Methods

86 HCC patients (40 VETC-positive and 46 VETC-negative) were prospectively enrolled. Diffusion-weighted images were acquired using six b-values (range from 0 to 3000 s/mm2). Various diffusion parameters derived from diffusion kurtosis (DK), stretched-exponential (SE), fractional-order calculus (FROC), and continuous-time random walk (CTRW) models, together with the conventional apparent diffusion coefficient (ADC) derived from the monoexponential model were calculated. All parameters were compared between VETC-positive and VETC-negative groups using an independent sample t-test or Mann-Whitney U test, and then the parameters with significant differences between the two groups were combined to establish a predictive model by binary logistic regression. Receiver operating characteristic (ROC) analyses were used to assess diagnostic performance.

Results

Among all studied diffusion parameters, only DKI_K and CTRW_α significantly differed between groups (P=0.002 and 0.004, respectively). For predicting the presence of VETC in HCC patients, the combination of DKI_K and CTRW_α had the larger area under the ROC curve (AUC) than the two parameters individually (AUC=0.747 vs. 0.678 and 0.672, respectively).

Conclusion

DKI_K and CTRW_α outperformed traditional ADC for predicting the VETC of HCC.

Association between vessels that encapsulate tumour clusters vascular pattern and hepatocellular carcinoma recurrence following liver transplantation

BACKGROUND

Vessels that encapsulate tumor clusters (VETC) is a novel vascular pattern seen on hepatocellular carcinoma (HCC) histology which has been shown to independently predict tumor recurrence and survival after liver resection. Its prognostic value in HCC patients receiving liver transplantation (LT) is unclear.

METHODS

We retrospectively studied consecutive adults who underwent deceased-donor LT with active HCC found on explant between 2010-2019. Tumor tissue was stained for CD34 and quantified for VETC. Primary and secondary endpoints were time to recurrence (TTR) and recurrence-free survival (RFS).

RESULTS

During the study period, 158 patients received LT where HCC was present on explant. VETC pattern was seen in 76.5% of explants. Patients with VETC-positive tumors spent longer on the waitlist (6.4 vs. 4.1 months, P=0.048), had higher median tumor numbers (2 vs. 1, P=0.001) and larger tumor sizes (20mm vs. 13mm, P<0.001) on explant pathology compared to those with VETC-negative tumors. Correspondingly, VETC-positive patients were more likely to be outside of accepted LT criteria for HCC. After 56.4 months median follow-up, 8.2% of patients developed HCC recurrence post-LT. On multivariable Cox regression, presence of VETC pattern did not predict TTR or RFS. However, the number of VETC-positive tumors on explant was an independent predictor of TTR (hazard ratio [HR] 1.411, P=0.001) and RFS (HR 1.267, P=0.014) after adjusting for other significant variables.

CONCLUSION

VETC pattern is commonly observed in HCC patients undergoing LT. The number of VETC-positive tumors, but not its presence, is an independent risk factor for TTR and RFS post-LT.

Nomogram Estimating Vessels Encapsulating Tumor Clusters in Hepatocellular Carcinoma From Preoperative Gadoxetate Disodium-Enhanced MRI

BACKGROUND

Vessels encapsulating tumor clusters (VETC) pattern is a novel microvascular pattern associated with poor outcomes of hepatocellular carcinoma (HCC). Preoperative estimation of VETC has potential to improve treatment decisions.

PURPOSE

To develop and validate a nomogram based on gadoxetate disodium-enhanced MRI for estimating VETC in HCC and to evaluate whether the estimations are associated with recurrence after hepatic resection.

STUDY TYPE

Retrospective.

POPULATION

A total of 320 patients with HCC and histopathologic VETC pattern assessment from three centers (development cohort:validation cohort = 173:147).

FIELD STRENGTH/SEQUENCE

A3.0  T/turbo spin-echo T2-weighted, spin-echo echo-planar diffusion-weighted, and 3D T1-weighted gradient-echo sequences.

ASSESSMENT

A set of previously reported VETC- and/or prognosis-correlated qualitative and quantitative imaging features were assessed. Clinical and imaging variables were compared based on histopathologic VETC status to investigate factors indicating VETC pattern. A regression-based nomogram was then constructed using the significant factors for VETC pattern. The nomogram-estimated VETC stratification was assessed for its association with recurrence.

STATISTICAL TESTS

Fisher exact test, t-test or Mann-Whitney test, logistic regression analyses, Harrell's concordance index (C-index), nomogram, Kaplan-Meier curves and log-rank tests. P value < 0.05 was considered statistically significant.

RESULTS

Pathological VETC pattern presence was identified in 156 patients (development cohort:validation cohort = 83:73). Tumor size, presence of heterogeneous enhancement with septations or with irregular ring-like structures, and necrosis were significant factors for estimating VETC pattern. The nomogram incorporating these indicators showed good discrimination with a C-index of 0.870 (development cohort) and 0.862 (validation cohort). Significant differences in recurrence rates between the nomogram-estimated high-risk VETC group and low-risk VETC group were found (2-year recurrence rates, 50.7% vs. 30.3% and 49.6% vs. 31.8% in the development and validation cohorts, respectively).

DATA CONCLUSION

The nomogram integrating gadoxetate disodium-enhanced MRI features was associated with VETC pattern preoperatively and with postoperative recurrence in patients with HCC.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 2.

DNA Damage Repair Classifier Defines Distinct Groups in Hepatocellular Carcinoma

Simple Summary

DNA repair pathways have been implicated in hepatocellular carcinoma outcomes. We found that hepatocellular carcinomas (HCC) could be separated into two groups (high and low) based on the overall expression of genes involved in DNA repair. Among the low repair group, there were three subgroups, one of which shared features of the high repair group. Given the important role of liver in metabolism and detoxification and its regenerative capacity, proliferation and DNA damage responses are critical in subdividing major biological categories of liver tumors. High repair samples showed more proliferative and regenerative signatures and had poorer outcomes versus the low repair that were more associated with the genes involved in normal liver biology. These biological groups suggest that dysregulation in endogenous liver processes promotes a pro-tumorigenic microenvironment that may facilitate tumor progression or identify tumors that require more substantial clinical intervention.

Abstract

DNA repair pathways have been associated with variability in hepatocellular carcinoma (HCC) clinical outcomes, but the mechanism through which DNA repair varies as a function of liver regeneration and other HCC characteristics is poorly understood. We curated a panel of 199 genes representing 15 DNA repair pathways to identify DNA repair expression classes and evaluate their associations with liver features and clinicopathologic variables in The Cancer Genome Atlas (TCGA) HCC study. We identified two groups in HCC, defined by low or high expression across all DNA repair pathways. The low-repair group had lower grade and retained the expression of classical liver markers, whereas the high-repair group had more clinically aggressive features, increased p53 mutant-like gene expression, and high liver regenerative gene expression. These pronounced features overshadowed the variation in the low-repair subset, but when considered separately, the low-repair samples included three subgroups: L1, L2, and L3. L3 had high DNA repair expression with worse progression-free (HR 1.24, 95% CI 0.81–1.91) and overall (HR 1.63, 95% CI 0.98–2.71) survival. High-repair outcomes were also significantly worse compared with the L1 and L2 groups. HCCs vary in DNA repair expression, and a subset of tumors with high regeneration profoundly disrupts liver biology and poor prognosis.

Vessels that encapsulate tumor clusters (VETC) pattern predicts the efficacy of adjuvant TACE in hepatocellular carcinoma

PURPOSE

Postoperative adjuvant trans-catheter arterial chemoembolization (TACE) is regarded as a common strategy for hepatocellular carcinoma (HCC) patients at a high risk of recurrence. However, there are currently no clinically available biomarkers to predict adjuvant TACE response. Vessels that encapsulate tumor clusters (VETC) can be used as an independent predictor of HCC prognosis. In this study, we aimed to explore whether the VETC pattern could predict adjuvant TACE benefit.

METHODS

Vascular pattern and HIF-1α expression were detected in immunohistochemistry. The survival benefit of adjuvant TACE therapy for patients with or without VETC pattern (VETC+ /VETC-) was evaluated.

RESULTS

The adjuvant TACE therapy obviously improved the TTR and OS in VETC+ patients, while adjuvant TACE therapy could not benefit from VETC- patients. Univariate and multivariate analysis revealed that adjuvant TACE therapy significantly improved the TTR and OS in VETC+ patients, but not in VETC- patients. In addition, the VETC+ , but not VETC- , patients could benefit from adjuvant TACE therapy in patients with high-risk factors of vascular invasion, larger tumor or multiple tumor. The mechanistic investigations revealed that the favorable efficacy of adjuvant TACE on VETC+ patients, but not VETC- ones, may be not due to the activation of HIF-1α pathway.

CONCLUSION

The VETC pattern may represent a novel and reliable factor for selecting HCC patients who may benefit from adjuvant TACE therapy, and the combination of VETC pattern and tumor characteristics may help stratify patients' outcomes and responses to adjuvant TACE therapy.

Prognostic Impact of Surgical Margin in Hepatectomy on Patients With Hepatocellular Carcinoma: A Meta-Analysis of Observational Studies

Objective

This study aims to comprehensively evaluate the prognostic impact of the surgical margin in hepatectomy on patients diagnosed with hepatocellular carcinoma (HCC).

Methods

A comprehensive and systematic search for eligible articles published in English before July 2021 was conducted across PubMed, Cochrane Library, Web of Science, and Embase electronic databases. The overall survival (OS) and disease-free survival (DFS) were the primary endpoints.

Results

In total, 37 observational studies with 12,295 cases were included in this meta-analysis. The results revealed that a wide surgical margin (≥1 cm) was associated with better OS (hazard ration (HR), 0.70; 95% confidence interval (CI), 0.63–0.77) and DFS (HR, 0.66; 95% CI, 0.61–0.71) compared to a narrow surgical margin (<1 cm). Subgroup analyses were conducted based on median follow-up time, gender, country, hepatitis B surface antigen (HBsAg) status, tumor number, and liver cirrhosis. The prognostic benefit of a wide surgical margin was consistent in most subgroups, however, analysis of studies from Western countries showed that margin width was not associated with prognosis.

Conclusion

In summary, a surgical margin wider than 1 cm prolongs the long-term prognosis of HCC patients compared to a surgical margin narrower than 1 cm.

Dual and opposing roles of the androgen receptor in VETC-dependent and invasion-dependent metastasis of hepatocellular carcinoma

BACKGROUND & AIMS

Contradictory roles of the androgen receptor (AR) in hepatocellular carcinoma (HCC) metastasis have been reported. We have shown that VETC (vessels encapsulating tumor clusters) mediates invasion-independent metastasis, whereas VETC^- HCCs metastasize in an invasion-dependent manner. Herein, we aimed to reveal the roles of AR in HCC metastasis.

METHODS

Mouse xenograft models, clinical samples, and cell models were used.

RESULTS

AR expression was significantly lower in HCCs with a VETC pattern, portal vein tumor thrombus, endothelium-coated microemboli or high recurrence rates. Overexpressing AR in VETC⁺ hepatoma cells suppressed VETC formation and intrahepatic metastasis but promoted pulmonary metastasis of mouse xenografts. AR decreased the transcription of Angiopoietin-2 (Angpt2), a factor essential for VETC formation, by binding to the Angpt2 promoter. The roles of AR in inhibiting VETC formation and intrahepatic metastasis were attenuated by restoring Angpt2 expression, suggesting that AR may repress VETC-dependent intrahepatic metastasis by inhibiting Angpt2 expression and VETC formation. On the other hand, AR upregulated Rac1 expression, promoted lamellipodia formation and increased cell migration/invasion. A Rac1 inhibitor abrogated the AR-mediated promotion of migration/invasion and pulmonary metastasis of VETC⁺ hepatoma cells, but did not affect the AR-mediated inhibition of intrahepatic metastasis. Furthermore, an AR inhibitor decreased Rac1 expression and attenuated both intrahepatic and pulmonary metastasis of VETC^- xenografts, an effect which was abrogated by restoring Rac1 expression. These data indicate that AR may facilitate the lung metastasis of VETC⁺ HCCs and both the liver/lung metastases of VETC^- HCCs by upregulating Rac1 expression and then promoting migration/invasion.

CONCLUSION

AR plays dual and opposing roles in VETC-dependent and invasion-dependent metastasis, which highlights the complex functions of AR and the importance of individualized cancer therapy.

LAY SUMMARY

In this study, we uncovered the dual and opposing roles of the androgen receptor in VETC (vessels encapsulating tumor clusters)-dependent and invasion-dependent metastasis of hepatocellular carcinoma (HCC). We elucidated the underlying mechanisms of these processes, which provided novel insights into the complex regulatory network of the androgen receptor in HCC metastasis and may have important implications for precision medicine.

Development and Validation of a Model Including Distinct Vascular Patterns to Estimate Survival in Hepatocellular Carcinoma

IMPORTANCE

Because of tumor heterogeneity, traditional clinical variables remain insufficient to predict recurrence, which impairs long-term survival among patients undergoing radical hepatectomy for hepatocellular carcinoma (HCC). Vessels encapsulating tumor clusters (VETC) constitute a novel vascular pattern distinct from microvascular invasion (MVI), representing biological aggressiveness of HCC.

OBJECTIVE

To establish a model to estimate individualized recurrence-free survival (RFS) in HCC by integrating VETC and MVI.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study included 498 patients undergoing radical hepatectomy for HCC from 5 academic centers in China from January 1, 2013, to December 31, 2016, and consisted of 3 cohorts: training (243 [48.8%]), internal validation (122 [24.5%]), and external validation (133 [26.7%]). Follow-up was completed on March 30, 2020, and the data were analyzed from December 1 to 31, 2020.

EXPOSURES

VETC, MVI, tumor number, and maximum tumor size.

MAIN OUTCOMES AND MEASURES

The primary end point was RFS. The risk score for relative recurrence and nomogram for absolute RFS probability were derived from the final model, which contained variables recommended by multivariate least absolute shrinkage and selection operator Cox proportional hazards regression analysis. Their performance was quantified using the Harrell concordance index (C index), the time-dependent area under the receiver operating characteristic curve, and calibration curves and was compared with 6 prognostic systems. Recurrence-free survival was estimated by the Kaplan-Meier method, and RFS curves were compared using a log-rank test.

RESULTS

Among the 498 patients, 432 (86.7%) were men; the mean (SD) age at diagnosis was 51.4 (11.3) years. Independent predictors for RFS identified included VETC, MVI, tumor number, and maximum tumor size, which were incorporated into the multivariate model (VMNS model). The C index (0.702; 95% CI, 0.653-0.752) for the VMNS score of the training cohort was significantly higher than those of 6 conventional systems (0.587 [95% CI, 0.535-0.638] to 0.657 [95% CI, 0.606-0.708]). Different recurrence risk groups defined by the VMNS score showed significantly different 2-year RFS (low-risk group, 81.4% [SE, 0.036]; medium-risk group, 62.1% [SE, 0.054]; high-risk group, 30.1% [SE, 0.079]; P < .001). Calibration curves of the VMNS nomogram showed good agreement between the nomogram-predicted RFS probability and actual RFS proportion. The internal and external validation cohorts confirmed the results.

CONCLUSIONS AND RELEVANCE

The VMNS model enabled individualized prognostication of RFS in patients with HCC undergoing curative resection.

The predictive value of vessels encapsulating tumor clusters in treatment optimization for recurrent early-stage hepatocellular carcinoma

Background

The predictive value of vessels encapsulating tumor clusters (VETC) in recurrent early‐stage hepatocellular carcinoma (HCC) remains unclear. Therefore, the aim of the present study was to investigate the prognostic significance of VETC in patients with recurrent early‐stage HCC after repeat hepatic resection (RHR) or radiofrequency ablation (RFA).

Methods

From December 2005 to December 2016, 138 patients receiving RHR and 188 patients receiving RFA were recruited. VETC was evaluated by immunohistochemical staining for CD34. The survival outcomes of patients with VETC pattern or not were investigated.

Results

There was no significant difference between the RHR and RFA groups in disease‐free survival (DFS) or overall survival (OS) as determined by the univariate analysis of the whole cohort. In the subgroup analysis of the VETC‐positive cohort, the patients in the RHR group showed a longer median DFS time in contrast to those in the RFA group (15.0 vs. 5.0 months, p = 0.001). Similarly, the patients in the RHR group showed a longer median OS time in contrast to those in the RFA group (39.5 vs. 19 months, p = 0.001). In the VETC‐negative cohort, no significant differences in DFS and OS rates between the RHR and RFA groups were observed (p > 0.05).

Conclusions

The results of our study suggested that RHR was relatively safe and superior to RFA in improving survival outcomes for recurrent early‐stage HCC after initial hepatectomy. Furthermore, the VETC pattern may represent a reliable marker for selecting HCC patients who may benefit from RHR.

Texture Analysis Based on Gd-EOB-DTPA-Enhanced MRI for Identifying Vessels Encapsulating Tumor Clusters (VETC)-Positive Hepatocellular Carcinoma

PURPOSE

To determine the potential findings associated with vessels encapsulating tumor clusters (VETC)-positive hepatocellular carcinoma (HCC), with particular emphasis on texture analysis based on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI.

METHODS

Eighty-one patients with VETC-negative HCC and 52 patients with VETC-positive HCC who underwent Gd-EOB-DTPA-enhanced MRI before curative partial hepatectomy were retrospectively evaluated in our institution. MRI texture analysis was performed on arterial phase (AP) and hepatobiliary phase (HBP) images. The least absolute shrinkage and selection operator (LASSO) logistic regression was used to select texture features most useful for identifying VETC-positive HCC. Univariate and multivariate analyses were used to determine significant variables for identifying the VETC-positive HCC in clinical factors and the texture features of MRI. Receiver operating characteristic (ROC) analysis and DeLong test were performed to compare the identified performances of significant variables for identifying VETC-positive HCC.

RESULTS

LASSO logistic regression selected 3 features in AP and HBP images, respectively. In multivariate analysis, the Log-sigma-4.0-mm-3D first-order Kurtosis derived from AP images (odds ratio [OR] = 4.128, P = 0.001) and the Wavelet-LHL-GLDM Dependence Non Uniformity Normalized derived from HBP images (OR = 2.280, P = 0.004) were independent significant variables associated with VETC-positive HCC. The combination of the two texture features for identifying VETC-positive HCC achieved an AUC value of 0.844 (95% confidence interval CI, 0.777, 0.910) with a sensitivity of 80.8% (95% CI, 70.1%, 91.5%) and specificity of 74.1% (95% CI, 64.5%, 83.6%).

CONCLUSION

Texture analysis based on Gd-EOB-DTPA-enhanced MRI can help identify VETC-positive HCC.

A new horizon in risk stratification of hepatocellular carcinoma by integrating vessels that encapsulate tumor clusters and microvascular invasion

BACKGROUND

Vessels that encapsulate tumor clusters (VETC) is a novel described vascular pattern different from microvascular invasion (MVI) for patients with hepatocellular carcinoma (HCC). The prognostic value of integrating VETC and MVI (VETC-MVI model) in HCC patients after resection remains unclear.

METHODS

From January 2013 to December 2016, 498 HCC patients who underwent curative resection were enrolled from five academic centers and stratified into different groups according to their VETC and MVI statuses. Overall survival (OS), disease-free survival (DFS), and early and late recurrence rates were evaluated.

RESULTS

The patients were divided into four subgroups: VETC^-/MVI^- (n = 277, 55.6%), VETC^-/MVI⁺ (n = 110, 22.1%), VETC⁺/MVI^- (n = 53, 10.6%), and VETC⁺/MVI⁺ (n = 58, 11.6%). The patients in the VETC⁺/MVI^- and VETC^-/MVI⁺ groups had similar long-term outcomes (OS: p = 0.402; DFS: p = 0.990), VETC^-/MVI^- patients showed the best prognosis, and VETC⁺/MVI⁺ patients had the worst prognosis. Further analysis revealed that the VETC-MVI model showed a similar stratification ability for early recurrence but not for late recurrence. The area under the curve values for early recurrence was 0.70, 0.63 and 0.64 for the VETC-MVI model, VETC, and MVI, respectively (VETC-MVI model vs VETC: p < 0.001; VETC-MVI model vs MVI: p = 0.004; VETC vs MVI: p = 0.539). Multivariate Cox regression analysis showed that the VETC-MVI model successfully predicted OS, DFS and early recurrence.

CONCLUSIONS

VETC status provides additional discriminative information for patients with either MVI^- or MVI⁺. A combination of VETC and MVI may help classify subtypes and predict the prognosis of HCC patients.

Imaging features based on Gd-EOB-DTPA-enhanced MRI for predicting vessels encapsulating tumor clusters (VETC) in patients with hepatocellular carcinoma

OBJECTIVE

To investigate the non-invasive prediction of hepatocellular carcinoma (HCC) with vessels encapsulating tumor clusters (VETC) based on qualitative and quantitative imaging features of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI.

METHODS

109 patients with pathologically confirmed HCC who underwent Gd-EOB-DTPA enhanced MRI and immunochemical staining for CD34 were retrospectively evaluated in our institution (the first affiliated hospital of Soochow university). Pre-operative imaging features of Gd-EOB-DTPA-enhanced MRI were qualitatively and quantitatively reviewed by radiologists. Significant variables for differentiating the VETC-positive and VETC-negative HCCs were identified in univariate and multivariate analyses. Receiver operating characteristic (ROC) analysis was performed to determine the optimal cut-off values for quantitative variables. The nomogram based on the coefficient of multivariate analysis was constructed to evaluate the probability of VETC-positive HCCs.

RESULTS

The multivariate analysis showed that the serum AST level >40 U  l^-1 (p = 0.007), non-rim diffuse and heterogeneous arterial phase hyperenhancement (p = 0.035), tumor-to-liver SI ratio of 1.135 or more on AP images (p = 0.001), and tumor-to-liver SI ratio of 0.585 or less on HBP images (p = 0.002) were significant predictors for predicting VETC-positive HCCs. Combing all four significant variables provided a diagnostic accuracy of 82.6%, sensitivity of 83.9%, specificity of 80.9% for identifying VETC status. The area under the receiver operating characteristics curve value of the logistical regression coefficient-based nomogram was 0.885 (95% confidence intervals, 0.824-0.946).

CONCLUSION

Qualitative and quantitative imaging features of Gd-EOB-DTPA-enhanced MRI integrating laboratory examination can provide good diagnostic performance.

ADVANCES IN KNOWLEDGE

VETC is a novel identified microvascular pattern; associations between imaging features and VETC status have not been investigated. Pre-operative diagnosis of VETC status in HCC is essential to help predict the outcome of patients and make a decision for the therapeutic schedule.

Factors Affecting Local and Intra Hepatic Distant Recurrence After Surgery for Hcc: An Alternative Perspective on Microvascular Invasion and Satellitosis - A Western European Multicentre Study

BACKGROUND

Few studies have focused on risk factors which may predict an intrahepatic local recurrence (LR) on the surgical edge rather than a distant recurrence (DR) in other liver segments after surgery for hepatocarcinoma (HCC). The purpose of this study was to assess the risk factors for both patterns of recurrence.

METHODS

An international, multicentre, retrospective study was conducted by collecting data on all consecutive patients with a first diagnosis of HCC who were treated between 2010 and 2017. The presence of macrovascular invasion was an exclusion criteria.

RESULTS

About 376 patients were enrolled, and, among them, 62 presented LR, while 90 had DR. Baseline characteristics were comparable between the two groups, but the DR group had a much higher rate of HCV infection (48.9% vs 29%, p 0.014) and a higher median nodule size (3.40 cm IQR 2.2-5.5 versus 3.0 cm IQR 2.0-5.0 in the LR group, p 0.025). A positive surgical margin (R1, HR 4.721; 95% CI 1.83-12.17; p 0.001) was the only independent risk factor for LR, while MVI (HR 1.837; 95% CI 1.03-3.77; p 0.039) and satellitosis (HR 2.440, 95% CI 1.43-3.77, p 0.001) were the only predictive factors for DR.

CONCLUSION

MVI and satellitosis are predictive factors of intrahepatic distant recurrence, configuring a probable hallmark of advanced systemic disease, regardless of the treatment. LR has to be considered the expression of surgical failure.

Effect of surgical margin on recurrence based on preoperative circulating tumor cell status in hepatocellular carcinoma

Background

High rates of recurrence after resection severely worsen hepatocellular carcinoma (HCC) prognosis. This study aims to explore whether circulating tumor cell (CTC) is helpful in determine the appropriate liver resection margins for HCC patients.

Methods

HCC patients who underwent liver resection were enrolled into training (n=117) or validation (n=192) cohorts, then classified as CTC-positive (CTC≥1) or CTC-negative (CTC=0). A standardized pathologic sampling method was used in the training cohort to quantify microvascular invasion (mVI) and the farthest mVI from the tumor (FMT).

Findings

CTC number positively correlated with mVI counts (r=0.655, P<0.001) and FMT (r=0.495, P<0.001). The CTC-positive group had higher mVI counts (P=0.032) and greater FMT P=0.008) than the CTC-negative group. In the CTC-positive group, surgical margins of >1 cm independently protected against early recurrence (training cohort, P=0.004; validation cohort, P=0.001) with lower early recurrence rates (training cohort, 20.0% vs. 65.1%, P=0.005; validation cohort, 36.4% vs. 65.1%, P=0.003) compared to surgical margins of ≤1 cm. No differences in postoperative liver function were observed between patients with margins >1 cm vs. ≤1 cm. Surgical margin size minimally impacted early postoperative HCC recurrence in CTC-negative patients when using 0.5 cm or 1 cm as the threshold.

Interpretations

Preoperative CTC status predicts mVI severity in HCC patients and is a potential factor for determining optimal surgical margin size to ensure disease eradication and conserve liver function. A surgical margin of >1 cm should be achieved for patients with positive CTC.

Funding

A full list of funding bodies that contributed to this study can be found in the Acknowledgement section.

Evaluation of Intra-Tumoral Vascularization in Hepatocellular Carcinomas

Intratumoral neovascularization has intricate effects on tumor growth, metastasis, and treatment. Over the last 30 years, Microvessel density (MVD) has been the standard method for laboratory and clinical evaluation of angiogenesis. Hepatocellular carcinoma (HCC) is a typical hypervascularized tumor, and the predictive value of MVD for prognosis is still controversial. According to previous viewpoints, this has been attributed to the determination of hotspot, counting methods, vascular endothelial markers, and different definitions of high and low vascular density; however, the heterogeneity of tumor angiogenesis patterns should be factored. The breakthroughs in artificial intelligence and algorithm can improve the objectivity and repeatability of MVD measurement, thus saving a lot of manpower. Presently, anti-angiogenesis therapy is the only effective systematic treatment for liver cancer, and the use of imaging technology-assisted MVD measurement is expected to be a reliable index for evaluating the curative effect. MVD in multinodular hepatocellular carcinoma represents a subject area with huge understudied potential, and exploring it might advance our understanding of tumor heterogeneity.

A novel prognostic nomogram based on microvascular invasion and hematological biomarkers to predict survival outcome for hepatocellular carcinoma patients

PURPOSE

This study aimed to develop and validate a nomogram for overall survival (OS) prediction in which combine clinical characteristics and hematological biomarkers in patients with hepatocellular carcinoma (HCC).

METHODS

We performed a retrospective analysis of 807 HCC patients. All the clinical data of these patients were collected through electronic medical record (EMR). The independent predictive variables were identified by cox regression analysis. We tested the accuracy of the nomograms by discrimination and calibration, and then plotted decision curves to assess the benefits of nomogram-assisted decisions in a clinical context, and compared with the TNM staging systems and microvascular invasion (MVI) on HCC prognosis.

RESULTS

The primary cohort consisted of 545 patients with clinicopathologically diagnosed with HCC from 2008 to 2013, while 262 patients from 2014 to 2016 in external validation cohort. Variables included in the nomograms were TNM Stage, microvascular invasion (MVI), alpha fetoprotein (AFP), platelet to lymphocyte ratio (PLR) and prothrombin time (PT). The C-index of nomogram was 0.768, which was superior than the C-index of TNM Stage (0.660, P < 0.001) and MVI(0.664, P < 0.001) alone in the primary cohort. In the validation cohort, the models had a C-index of 0.845, and were also statistically higher when compared to C-index values for TNM Stage (0.687, P < 0.001) and MVI(0.684, P < 0.001). Calibration curves showed adequate calibration of predicted and reported OS prediction throughout the range of HCC outcomes. Decision curve analysis demonstrated that the nomogram was clinically useful than the TNM Stage and MVI alone. Moreover, patients were divided into three distinct risk groups for OS by the nomogram: low risk group, middle risk group and a high risk group, respectively.

CONCLUSION

The nomogram presents more accurate and useful prognostic power, which could be used to predict OS for patients with HCC.

Vessels That Encapsulate Tumor Clusters (VETC) Pattern Is a Predictor of Sorafenib Benefit in Patients with Hepatocellular Carcinoma

Sorafenib is the most recommended first-line systemic therapy for advanced hepatocellular carcinoma (HCC). Yet there is no clinically applied biomarker for predicting sorafenib response. We have demonstrated that a vascular pattern, named VETC (Vessels that Encapsulate Tumor Clusters), facilitates the release of whole tumor clusters into the bloodstream; VETC-mediated metastasis relies on vascular pattern, but not on migration and invasion of cancer cells. In this study, we aimed to explore whether vascular pattern could predict sorafenib benefit. Two cohorts of patients were recruited from four academic hospitals. The survival benefit of sorafenib treatment for patients with or without the VETC pattern (VETC⁺ /VETC^- ) was investigated. Kaplan-Meier analyses revealed that sorafenib treatment significantly reduced death risk and prolonged overall survival (OS; in cohort 1/2, P = 0.004/0.005; hazard ratio [HR] = 0.567/0.408) and postrecurrence survival (PRS; in cohort 1/2, P = 0.001/0.002; HR = 0.506/0.384) in VETC⁺ patients. However, sorafenib therapy was not beneficial for VETC^- patients (OS in cohort 1/2, P = 0.204/0.549; HR = 0.761/1.221; PRS in cohort 1/2, P = 0.121/0.644; HR = 0.728/1.161). Univariate and multivariate analyses confirmed that sorafenib treatment significantly improved OS/PRS in VETC⁺ , but not VETC^- , patients. Further mechanistic investigations showed that VETC⁺ and VETC^- HCCs displayed similar levels of light chain 3 (LC3) and phosphorylated extracellular signal-regulated kinase (ERK) in tumor tissues (pERK) or endothelial cells (EC-pERK), and greater sorafenib benefit was consistently observed in VETC⁺ HCC patients than VETC^- irrespective of levels of pERK/EC-pERK/LC3, suggesting that the different sorafenib benefit between VETC⁺ and VETC^- HCCs may not result from activation of Raf/mitogen-activated protein kinase kinase (MEK)/ERK and vascular endothelial growth factor (VEGF)A/VEGF receptor 2 (VEGFR2)/ERK signaling or induction of autophagy. Conclusion: Sorafenib is effective in prolonging the survival of VETC⁺ , but not VETC^- , patients. VETC pattern may act as a predictor of sorafenib benefit for HCC.

Roles of exosomes in liver metastases: Novel diagnosis and treatment choices

Tumors tend to metastasize to the liver. Premetastatic niche formation is a vital step in liver metastasis. Tumor-derived exosomes can influence premetastatic niche formation from three aspects: vascular leakiness and angiogenesis, recruitment of nonresident cells, and changes in local resident cells. Exosomes from other tissues, such as mesenchymal stem cell-derived exosomes and engineered exosomes, also have therapeutic potential, but further research on these exosomes is required. Based on the mechanism of premetastatic niche formation, we summarize the therapeutic and diagnostic potential of exosomes in inhibiting liver metastases in this review in an attempt to provide new avenues for the prevention and treatment of liver metastases.

Prognostic evaluation of NANOG and OCT4 expression for posttransplantation hepatocellular carcinoma recurrence

Postoperative hepatocellular carcinoma (HCC) recurrence and metastasis throw great threaten to its overall survival (OS). This paper focus on exploring the prognostic significance of NANOG and OCT4 expression in HCC recurrence and OS after liver transplantation. Eighty-six patients who meet University of California San Francisco (UCSF) criteria and underwent liver transplantation in Tianjin First Central Hospital between August 2010 and August 2013 were included. Expression of NANOG and OCT4 was determined by immunohistochemistry. The relationships between NANOG and OCT4 expression with tumor recurrence, tumor count, histology stage, lymph node metastasis (LNM) and microvascular invasion (MVI) were explored through the χ² test and Cox regression analysis. We found that 19/26 and 20/24 patients with positive expression of NANOG and OCT4 relapsed. Combination of NANOG and OCT4 expression was indicated as valuable prognostic signature for HCC recurrence prediction (P < 0.0011). Besides, we identified other key factors with significant correlations with recurrence, such as LNM (P = 0.011) and MVI (P = 0.024). Strikingly, recurrence sites could significantly affect recurrence time (P = 0.0062) and patients with recurrence in transplanted liver have longer recurrence time. In conclusions, we analyzed the relationships between NANOG/OCT4 expression, clinicopathology features, HCC recurrence, and OS after liver transplantation for the first time. Combination of NANOG, OCT4, LNM, histopathological stage, and MVI may be predictor for HCC recurrence posttransplantation. Comprehensive of histopathological stage grade and LNM were considered as prognosis factor for OS after liver transplantation. This should be helpful for treatment method selection for HCC patients after liver transplantation.

CD103+ tumor-infiltrating lymphocytes predict favorable prognosis in patients with esophageal squamous cell carcinoma

As an indispensable factor in preventing the recirculation of tissue lymphocytes to the lymphatic and blood systems, the integrin CD103 has enabled the characterization of lymphocyte populations in non-lymphoid tissues and organs. However, the expression, distribution, and clinical significance of CD103⁺ tumor-infiltrating lymphocytes (TILs) in esophageal squamous cell carcinoma (ESCC) remain unclear. In the present study, we included tumor and adjacent non-tumor tissue specimens from 198 patients with ESCC who had undergone surgical resection. Immunohistochemistry and immunofluorescence were used to detect CD103⁺ TIL distribution, as well as the co-expression of CD103 and T cell markers and functional molecules. Kaplan-Meier analysis and the Cox proportional hazards model were used to estimate the prognostic value of CD103⁺ TILs. The results showed that CD103⁺ TILs were predominantly located in adjacent non-tumor tissues compared with tumor tissues (P < 0.0001). Immunofluorescence double staining revealed that CD8⁺ T cells, but not CD4⁺ T cells, comprised the majority of CD103-expressing cells. Most of these CD103-expressing cells co-expressed CTLA-4 and granzyme B rather than the exhaustion marker PD-1. High density of intratumoral CD103⁺ TIL is associated with longer overall survival (OS) and disease-free survival (DFS) in both the internal (OS, P = 0.0004 and DFS, P = 0.0002) and external (OS, P = 0.038 and DFS, P = 0.12) cohorts. Multivariate Cox analysis showed the density of CD103⁺ TILs was an independent positive prognostic factor for OS (hazards ratio [HR] = 0.406; P = 0.0003 in the internal cohort; HR = 0.328, P = 0.01, in the external cohort) and DFS (HR = 0.385; P = 0.0002 in the internal cohort; HR = 0.270, P = 0.003, in the external cohort). Our findings indicate that CD103⁺ TILs might play an important role in the tumor microenvironment, and intratumoral CD103⁺ TILs could serve as a promising prognostic marker in ESCC.

Liver regeneration microenvironment in liver cancer: Research progress and prospect

The proposal of the new concept of liver regeneration microenvironment in liver cancer (LC) contributes to the overall understanding of how LC microenvironment influences the occurrence and development of LC through liver regeneration microenvironment, inflammatory microenvironment, immune microenvironment, and angiogenesis microenvironment, and helps explore more comprehensive and effective preventive and therapeutic measures for LC to improve the capability of LC prevention and cure. On the basis of eliminating hepatocellular carcinoma cells or tissues, the maintenance of normal liver regeneration and improvement of liver regeneration microenvironment in LC is an important strategy for LC prevention and treatment. Improving liver regeneration microenvironment to prevent or reverse the occurrence, development, and metastasis of LC should be an important research direction of LC prevention and treatment research. In recent years, traditional Chinese medicine research and application have made some progress in improving liver regeneration microenvironment to prevent or reverse the occurrence, development, recurrence, and metastasis of LC. However, it remains to be solved on how to accurately reveal the comprehensive network mechanism and how to provide advanced evidence-based medical evidence, which needs further extensive research.

Finally, a Minimally Invasive Option for Intrahepatic Inferior Vena Cava Invasion by Hepatocellular Carcinoma

Background

Major vessel invasion is a late manifestation of hepatocellular carcinoma, which may directly result in mortality if left untreated. Surgical resection may be an option for select patients; however, surgery may be contraindicated. Contraindications include multifocal disease, poor liver reserve, inability to tolerate surgery, and patient preference. Cryoablation is a minimally invasive therapy utilized for treating hepatic neoplasms by subjecting them to extreme cold temperatures. The "thermal sink" effect describes cryoablation near flowing blood such as that found in high volumes within major vascular structures. Thermodynamics dictates that proximity to the flowing intravascular compartment will decrease ice formation, and therefore, tumor destruction.

Methods

This report describes a novel palliative technique to induce temporary cessation of the blood flow in the intrahepatic inferior vena cava (IVC), thus enabling the operator to perform cryoablation targeting invasive cancer within.

Results

Adequate ablation using this technique allowed a patient with IVC invasion 9 months of survival.

Conclusion

Quality of life during this time was maximized, as recovery time from this procedure is minimal.

Adjuvant transarterial chemoembolization to improve the prognosis of hepatocellular carcinoma following curative resection

The present study aimed to investigate the prognostic factors for recurrence of hepatocellular carcinoma (HCC) following curative resection, and evaluate the efficacy of postoperative adjuvant transarterial chemoembolization (TACE) in improving prognosis. A total of 166 patients who underwent curative resection followed by adjuvant TACE, and 190 patients who underwent curative resection alone were studied retrospectively. Univariate and multivariate analyses were performed to investigate the risk factors of recurrence. Separated based on risk factors, subgroup studies were conducted and the association between TACE and recurrence rates was examined. Postoperative overall survival rates were determined using the Kaplan-Meier method and differences between the two therapeutic strategies were identified through log-rank analysis. Computerized tomography (CT)/magnetic resonance imaging (MRI) images were used to evaluate the function of postoperative adjuvant TACE for enhancing the efficacy of CT/MRI in detecting recurrence. The results of the univariate and multivariate analyses revealed that tumor capsule invasion, vascular invasion, and multiple nodules were risk factors of early recurrence. For patients with these risk factors, recurrence rates were markedly decreased at 6 and 12 months, but not at 18 and 24 months, if TACE was added to curative resection. The hepatitis B virus (HBV) was a risk factor for late recurrence. Postoperative TACE was not effective in reducing the recurrence rate in patients with HBV. Survival increased following curative resection with TACE compared with curative resection alone. Furthermore, adjuvant TACE enhanced the efficacy of CT/MRI in detecting recurrence. Postoperative adjuvant TACE may improve the prognosis of HCC following curative resection.

Expression patterns of programmed death ligand 1 correlate with different microenvironments and patient prognosis in hepatocellular carcinoma

Background

Recent clinical studies have suggested that programmed death ligand 1 (PD-L1) expression in a tumour could be a potential biomarker for PD-L1/PD-1 blockade therapies.

Methods

To better characterise PD-L1 expression in hepatocellular carcinoma (HCC), we analysed its expression patterns in 453 HCC patients by double staining for CD68 and PD-L1 using the Tyramide Signal Amplification Systems combined with immunohistochemistry. We also investigated its correlation with clinical features, prognosis and immune status.

Results

The results showed that PD-L1 expression on tumour cells (TCs) was negatively associated with patients’ overall survival (OS; P = 0.001) and relapse-free survival (RFS; P = 0.006); however, PD-L1 expression on macrophages (Mφs) was positively correlated with OS (P = 0.017). Multivariate analysis revealed that PD-L1 expression on TCs and Mφs were both independent prognostic factors for OS (hazard ratio (HR) = 1.168, P = 0.004 for TC-PD-L1; HR = 0.708, P = 0.003 for Mφ-PD-L1). Further studies showed that Mφ-PD-L1⁺ tumours exhibited an activated immune microenvironment, with high levels of CD8⁺ T-cell infiltration and immune-related gene expression.

Conclusion

Our study provided a novel methodology to evaluate PD-L1 expression in the tumour microenvironment, which might help to select patients who would benefit from anti-PD-1/PD-L1 immunotherapies.

Identification and Functional Characterization of Long Non-coding RNA MIR22HG as a Tumor Suppressor for Hepatocellular Carcinoma

Long non-coding RNAs (lncRNAs) have recently been identified as critical regulators in tumor initiation and development. However, the function of lncRNAs in human hepatocellular carcinoma (HCC) remains largely unknown. Our study was designed to explore the biological function and clinical implication of lncRNA MIR22HG in HCC. Methods: We evaluated MIR22HG expression in 52-patient, 145-patient, TCGA, and GSE14520 HCC cohorts. The effects of MIR22HG on HCC were analyzed in terms of proliferation, invasion, and metastasis, both in vitro and in vivo. The mechanism of MIR22HG action was explored through bioinformatics, luciferase reporter, and RNA immunoprecipitation analyses. Results:MIR22HG expression was significantly down-regulated in 4 independent HCC cohorts compared to that in controls. Its low expression was associated with tumor progression and poor prognosis of patients with HCC. Forced expression of MIR22HG in HCC cells significantly suppressed proliferation, invasion, and metastasis in vitro and in vivo. Mechanistically, MIR22HG derived miR-22-3p to target high mobility group box 1 (HMGB1), thereby inactivating HMGB1 downstream pathways. Additionally, MIR22HG directly interacted with HuR and regulated its subcellular localization. MIR22HG competitively bound to human antigen R (HuR), resulting in weakened expression of HuR-stabilized oncogenes, such as β-catenin. Furthermore, miR-22-3p suppression, HuR or HMGB1 overexpression rescued the inhibitory effects caused by MIR22HG overexpression. Conclusion: Our findings revealed that MIR22HG plays a key role in tumor progression by suppressing the proliferation, invasion, and metastasis of tumor cells, suggesting its potential role as a tumor suppressor and prognostic biomarker in HCC.

Liver regeneration microenvironment of hepatocellular carcinoma for prevention and therapy

Research on liver cancer prevention and treatment has mainly focused on the liver cancer cells themselves. Currently, liver cancers are no longer viewed as only collections of genetically altered cells but as aberrant organs with a plastic stroma, matrix, and vasculature. Improving the microenvironment of the liver to promote liver regeneration and repair by affecting immune function, inflammation and vasculature can regulate the dynamic imbalance between normal liver regeneration and repair and abnormal liver regeneration, thus improving the microenvironment of liver regeneration for the prevention and treatment of liver cancer. This review addresses the basic theory of the liver regeneration microenvironment, including the latest findings on immunity, inflammation and vasculature. Attention is given to the potential design of molecular targets in the microenvironment of hepatocellular carcinoma (HCC). In an effort to improve the liver regeneration microenvironment of HCC, researchers have extensively utilized the enhancement of immunity, anti-inflammation and the vasculature niche, which are discussed in detail in this review. In addition, the authors summarize the latest pro-fibrotic transition characteristics of the vascular niche and review potential cell therapies for liver disease.

Prognostic value of a novel risk classification of microvascular invasion in patients with hepatocellular carcinoma after resection

Objectives

The present research aimed to evaluate the prognostic value of a novel risk classification of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) after resection.

Methods

A total of 295 consecutive HCC patients underwent hepatectomy were included in our study. We evaluated the degree of MVI according to the following three features: the number of invaded microvessels (≤5 vs >5), the number of invading carcinoma cells (≤ 50 vs >50), the distance of invasion from tumor edge (≤1 cm vs >1 cm).

Results

All patients were divided into three groups according to the three risk factors of MVI: non-MVI group (n=180), low-MVI group (n=60) and high-MVI group (n=55). The overall survival (OS) and recurrence-free survival (RFS) rates of high-MVI group were significantly poorer than those of low-MVI and non-MVI groups (P<0.001 and P=0.001; P<0.001 and P=0.003). Multivariate analysis showed high-MVI, type of resection, ICG-R15 and tumor size were risk factors for OS after hepatectomy. High-MVI, type of resection and tumor size were risk factors for RFS. In subgroup analyses, the OS and RFS rates of low-MVI and non-MVI groups were better than high-MVI group regardless of tumor size. In high-MVI group, anatomical liver resection (n=28) showed better OS and RFS rates compared with non-anatomical liver resection (n=29) (P=0.012 and P=0.002).

Conclusions

The novel risk classification of MVI based on histopathological features is valuable for predicting prognosis of HCC patients after hepatectomy.

Prognostic factors in patients with recurrent hepatocellular carcinoma treated with salvage liver transplantation: a single-center study

Although salvage liver transplantation (LT) has been widely adopted as a treatment for recurrent hepatocellular carcinoma(HCC), candidate selection criteria have not been established. This single-center study aimed to identify risk factors associated with HCC recurrence and survival following salvage LT. The study included 74 patients treated with salvage LT between October 2001 and February 2013. The median follow-up was 37.2 months after LT. There were 29 cases of HCC recurrence and 31 deaths following LT. Microvascular invasion at the time of liver resection, a time interval to post-LR HCC recurrence of ≤ 12months, an alpha-fetoprotein level at LT greater than 200 ng/mL, and having undergone LT outside of the UCSF criteria were independent risk factors for HCC recurrence after salvage LT. Patients with no more than one risk factor had a 5-year recurrence-free survival rate of 71.2% compared to 15.9% in patients with two or more risk factors. These findings suggest that to avoid post-LT HCC recurrence and a dismal prognosis, patients with no more than one risk factor for recurrence should be given priority for salvage LT. These criteria may improve the outcomes of patients treated with salvage LT and facilitate the effective use of limited organ supplies.

Monocytes/Macrophages promote vascular CXCR4 expression via the ERK pathway in hepatocellular carcinoma

We recently identified CXCR4 as a novel vascular marker for vessel sprouting in hepatocellular carcinoma (HCC) tissues. Thus, CXCR4⁺ endothelial cells (ECs) could serve as a potential predictor for patients who may benefit from sorafenib treatment; however, the mechanism that regulates vascular CXCR4 expression in HCC remains largely unknown. Here, we revealed a large number of monocytes/macrophages (Mo/Mϕ) to be selectively enriched in the perivascular areas of CXCR4⁺ vessels in HCC samples. The depletion of Mo/Mϕ with gadolinium chloride (GdCl₃) or zoledronic acid (ZA) treatment significantly reduced vascular CXCR4 expression in HCC tumors. This phenomenon was also confirmed in CCR2-KO mice, which exhibited reduced infiltration of inflammatory Mo/Mϕ in tumor tissues. Mechanistic studies revealed that inflammatory cytokines derived from tumor conditioned Mo/Mϕ, especially TNF-α, could up-regulate CXCR4 expression on ECs. TNF-α-induced activation of the Raf-ERK pathway, but not Notch signaling, was responsible for the expression of CXCR4. Moreover, the combination treatment of sorafenib with ZA was associated with improved anti-tumor efficacy by significantly reducing vascular CXCR4 expression. These findings revealed that Mo/Mϕ could regulate CXCR4 expression in the tumor vasculature. Thus, the inhibition of Mo/Mϕ inflammation might enhance the treatment efficacy of sorafenib in HCC.

Microenvironment of liver regeneration in liver cancer

The occurrence and development of liver cancer are essentially the most serious outcomes of uncontrolled liver regeneration. The progression of liver cancer is inevitably related to the abnormal microenvironment of liver regeneration. The deterioration observed in the microenvironment of liver regeneration is a necessary condition for the occurrence, development and metastasis of cancer. Therefore, the use of a technique to prevent and treat liver cancer via changes in the microenvironment of liver regeneration is a novel strategy. This strategy would be an effective way to delay, prevent or even reverse cancer occurrence, development and metastasis through an improvement in the liver regeneration microenvironment along with the integrated regulation of multiple components, targets, levels, channels and time sequences. In addition, the treatment of "tonifying Shen (Kidney) to regulate liver regeneration and repair by affecting stem cells and their microenvironment" can regulate "the dynamic imbalance between the normal liver regeneration and the abnormal liver regeneration"; this would improve the microenvironment of liver regeneration, which is also a mechanism by which liver cancer may be prevented or treated.

Cancer metastasis: issues and challenges

Metastasis is the major cause of treatment failure in cancer patients and of cancer-related deaths. This editorial discusses how cancer metastasis may be better perceived and controlled. Based on big-data analyses, a collection of 150 important pro-metastatic genes was studied. Using The Cancer Genome Atlas datasets to re-analyze the effect of some previously reported metastatic genes—e.g., JAM2, PPARGC1A, SIK2, and TRAF6—on overall survival of patients with renal and liver cancers, we found that these genes are actually protective factors for patients with cancer. The role of epithelial–mesenchymal transition (EMT) in single-cell metastasis has been well-documented. However, in metastasis caused by cancer cell clusters, EMT may not be necessary. A novel role of epithelial marker E-cadherin, as a sensitizer for chemoresistant prostate cancer cells by inhibiting Notch signaling, has been found. This editorial also discusses the obstacles for developing anti-metastatic drugs, including the lack of high-throughput technologies for identifying metastasis inhibitors, less application of animal models in the pre-clinical evaluation of the leading compounds, and the need for adjustments in clinical trial design to better reflect the anti-metastatic efficacy of new drugs. We are confident that by developing more effective high-throughput technologies to identify metastasis inhibitors, we can better predict, prevent, and treat cancer metastasis.

For robust big data analyses: a collection of 150 important pro-metastatic genes

Metastasis is the greatest contributor to cancer-related death. In the era of precision medicine, it is essential to predict and to prevent the spread of cancer cells to significantly improve patient survival. Thanks to the application of a variety of high-throughput technologies, accumulating big data enables researchers and clinicians to identify aggressive tumors as well as patients with a high risk of cancer metastasis. However, there have been few large-scale gene collection studies to enable metastasis-related analyses. In the last several years, emerging efforts have identified pro-metastatic genes in a variety of cancers, providing us the ability to generate a pro-metastatic gene cluster for big data analyses. We carefully selected 285 genes with in vivo evidence of promoting metastasis reported in the literature. These genes have been investigated in different tumor types. We used two datasets downloaded from The Cancer Genome Atlas database, specifically, datasets of clear cell renal cell carcinoma and hepatocellular carcinoma, for validation tests, and excluded any genes for which elevated expression level correlated with longer overall survival in any of the datasets. Ultimately, 150 pro-metastatic genes remained in our analyses. We believe this collection of pro-metastatic genes will be helpful for big data analyses, and eventually will accelerate anti-metastasis research and clinical intervention.

Epithelial-Mesenchymal Transition is Superior to Vessels-Encapsulate Tumor Cluster in Promoting Metastasis of Hepatocellular Carcinoma: a Morphological Evidence

Purpose Vessels-encapsulate tumor cluster (VETC) is a vascular pattern distinct from classical capillary-like pattern. It is reported that VETC structure is common in hepatocellular carcinoma (HCC) and can promote HCC metastasis in an epithelial-mesenchymal transition (EMT)-independent but VETC-dependent manner. However, the main metastatic manner of HCC containing both VETC and classical vascular structure (we called VETC±) is unknown. Methods Vascular pattern types and E-cadherin expression were evaluated by immunohistochemical staining in 168 HCC tissues, 50 pairs of primary HCC tissues and intrahepatic metastatic lesions, as well as 12 pairs of primary HCC tissues and major portal vein tumor thrombus. Survival and recurrence rates were evaluated using Kaplan-Meier analysis. The multivariate Cox proportional hazards model was used to determine the independent prognostic factors of HCC. Results VETC± cases were more common than VETC+ cases (HCC tissues with a VETC pattern fully distributed in the HCC section) in HCC. Statistical analysis showed that VETC± was an independent predictor of survival and recurrence. Furthermore, E-cadherin was positively correlated with the presence of VETC structure. In the case of HCCs with VETC±, their metastases (both intrahepatic and major vascular) were more likely to be VETC negative. Conclusions Our findings suggest that EMT may be superior to VETC in promoting HCC metastasis. Thus, both anti-EMT and anti-VETC agents should be considered in the case of HCC with VETC±.

Microcirculation of liver cancer, microenvironment of liver regeneration, and the strategy of Chinese medicine

Microcirculation of liver cancer is the micro-vascular system which comes from the tissue of liver cancer. It can offer the nutritional requirement for accelerating the cancer cell proliferation and metastasis. The intrinsic mechanism of angiogenesis is the key link in the formation of liver cancer microcirculation system. Liver regeneration microenvironment also plays an important role in the construction of liver cancer microcirculation, through the improvement of liver regeneration microenvironment affecting tumor microcirculation is the new strategy of prevention and treatment of liver cancer. In recent years, it is found that many kinds of Chinese medicine can inhibit angiogenesis, decrease the microvessel density, and delay or prevent the development of liver cancer.

Second Hepatectomy Improves Survival in Patients With Microvascular Invasive Hepatocellular Carcinoma Meeting the Milan Criteria

Microvascular invasion (MVI) is a strong risk factor for patients with hepatocellular carcinoma (HCC) meeting the Milan criteria and who have received curative hepatectomy. The relevance of a second hepatectomy in patients with MVI-positive recurrent HCC remains controversial. We had 329 cases of HCC hepatectomy meeting the Milan criteria and compared data on patient demographics, liver function, and tumor pathology between MVI-positive and MVI-negative group. We analyzed potential risk factors of overall survival (OS) and disease-free survival (DFS). Furthermore, newly developed pathological features following the second hepatectomy were also analyzed.The median OS and DFS were significantly superior in the MVI-negative group than in the MVI-positive group, 61 (10-81) versus 49 (11-82) months (P < 0.01) and 41 (7-75) versus 13 (3-69) months (P <  0.01), respectively. The presence of MVI and a total tumor diameter >3 cm were independent risk factors associated with both OS and DFS. Overall survival was significantly improved by a second hepatectomy in the MVI-positive group compared with the original MVI-positive group, 60 (26-82) versus 49 (11-82) months, respectively. This was now comparable to the MVI-negative group, 60 (26-82) versus 61 (10-81) months (P = 0.72). A second hepatectomy was consistently associated with better survival in the MVI-negative group as compared to the MVI-positive group. A second hepatectomy improves survival in patients with MVI HCC meeting the Milan criteria. The biology of MVI may change following a second hepatectomy. The absence of MVI is a good prognostic sign for patients undergoing second hepatectomy.