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

Characterizing hepatocellular carcinoma stem markers and their corresponding susceptibility to NK-cell based immunotherapy

Introduction

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and is the fourth-leading cause of all cancer-related deaths around the world. Liver transplantation, surgery, and local ablation are curative therapies for early-stage HCC. However, post-treatment outcomes can vary based on histopathologic stage. Poorly-differentiated HCC are associated with higher rates of tumor progression and lower overall survival compared to well-differentiated HCC after therapy. In this study, we aimed to characterize the cancer stem cell (CSC) profile of histopathologically-proven well and poorly-differentiated HCCs in an in-vitro environment. We characterized the stem-like profile of each type of HCC based on their surface markers and susceptibility to NK cell-mediated cytotoxicity.

Methods

Flow cytometry was used to quantify differential expression of MHC-class I, CD54, and CD44 between well- and poorly-differentiated HCCs. Primary untreated NK cells, IL-2 stimulated primary NK cells, and supercharged (sNK) cell-mediated cytotoxicity was assessed against well- and poorly-differentiated HCCs. IFN-γ supernatant from each respective NK cell experimental arm was also used to induce differentiation of HCCs. Finally, we characterized the temporal NK effector cell cytotoxicity using real-time quantitative analysis of imaging and impedance (eSight study).

Results

Poorly-differentiated HCCs demonstrated low surface expression of MHC-class I and CD54, and high expression of CD44. Treatment of NK cells secreted IFN-γ or IFN-γ cytokine induced differentiation in HCCs. Poorly-differentiated HCCs in comparison to well-differentiated HCC were more susceptible to NK cell-mediated cytotoxicity in primary NK cells, IL-2 stimulated primary NK cells, and sNK cells. sNK cells induced significantly higher cytotoxicity against well-differentiated HCCs in comparison to untreated or IL-2-stimulated primary NK cells. These findings were recapitulated with real-time quantitative imaging analysis.

Conclusions

Poorly-differentiated HCCs were found to have surface marker patterns of CSCs, making them highly susceptible to NK cell-based immunotherapy. NK-cell based therapy can potentially be leveraged as a neoadjuvant or adjuvant therapy in poorly-differentiated HCCs. Supercharged NK cells, which can be rapidly expanded to therapeutic levels, are uniquely capable of lysing both poorly- and well-differentiated HCCs. This finding suggests that sNK cells not only exhibit enhanced features against NK cells' targets but also are capable of activating T cells to induce cytotoxicity against well-differentiated HCCs with high expression of MHC class I.

Prognostic Factors of Liver Transplantation for Hepatocellular Carcinoma: A Surveillance, Epidemiology, and End Results (SEER) Database Analysis

OBJECTIVE

We aimed to identify new, more accurate risk factors of liver transplantation for liver cancer through using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Using the SEER database, we identified patients that had undergone surgical resection for non-metastatic hepatocellular carcinoma (HCC) and subsequent liver transplantation between 2010 and 2017. Overall survival (OS) was estimated using Kaplan-Meier plotter. Cox proportional hazards regression modelling was used to identify factors independently associated with recurrent disease [presented as adjusted hazard ratios (HR) with 95% CIs].

RESULTS

Totally, 1530 eligible patients were included in the analysis. There were significant differences in ethnicity (P=0.04), cancer stage (P<0.001), vascular invasion (P<0.001) and gall bladder involvement (P<0.001) between the groups that survived, died due to cancer, or died due to other causes. In the Cox regression model, there were no significant differences in OS at 5 years with different operative strategies (autotransplantation versus allotransplantation), nor at survival at 1 year with neoadjuvant radiotherapy. However, neoadjuvant radiotherapy did appear to improve survival at both 3 years (HR: 0.540, 95% CI: 0.326-0.896, P=0.017) and 5 years (HR: 0.338, 95% CI: 0.153-0.747, P=0.007) from diagnosis.

CONCLUSION

This study demonstrated differences in patient characteristics between prognostic groups after liver resection and transplantation for HCC. These criteria can be used to inform patient selection and consent in this setting. Preoperative radiotherapy may improve long-term survival post-transplantation.

Cd34 Immunostaining Adds Specificity To Microvascular invasion Analysis in Hepatocellular Carcinoma

Introduction

Hepatocellular carcinoma is the most common primary neoplasia of the liver. Microvascular invasion predicts outcome and defines tumor staging. However, its diagnosis is still a challenge. The present study aims to evaluate inter and intraobserver agreement in identifying the presence of microvascular invasion using conventional and immunohistochemistry histology.

Methods

Three pathologists performed the analysis of 76 hepatocellular carcinoma explants to characterize the presence of microvascular invasion using the hematoxylin/eosin stain and immunohistochemistry for CD34. The evaluations were made individually, in two distinct moments. Results were analyzed by the Kappa's coefficient and ROC curves.

Results

Our study demonstrated similar agreement for microvascular invasion between hematoxylin/eosin and CD34 methods. However, the intraobserver agreement values for both methods were higher than the interobserver ones. The accuracy of CD34 in relation to hematoxylin/eosin by ROC curves in intraobserver analysis tends to a high specificity, ranging from 82.1 to almost 100%, with sensitivity of 46.9% to 81.1%. In interobserver analysis, CD34 also has a high specificity (84.3% to 85.5%) while its sensitivity is a little shorter (81.2% to 84.3%).

Conclusion

Intraobserver higher agreement allows us to suppose that pathologists employed own criteria to evaluate vascular invasion, reinforcing the need of standardization. ROC Curves analysis showed that the CD34 method is more specific than sensitive. Therefore, immunohistochemistry for CD34 should not be used routinely, but it could be useful to help confirming invasion previously seen by conventional histology.

Supercharged NK Cell-Based Immuotherapy in Humanized Bone Marrow Liver and Thymus (Hu-BLT) Mice Model of Oral, Pancreatic, Glioblastoma, Hepatic, Melanoma and Ovarian Cancers

In this paper, we review a number of in vitro and in vivo studies regarding the efficacy of supercharged NK (sNK) cell therapy in elimination or treatment of cancer. We have performed studies using six different types of cancer models of oral, pancreatic, glioblastoma, melanoma, hepatic and ovarian cancers using hu-BLT mice. Our in vitro studies demonstrated that primary NK cells preferentially target cancer stem-like cells (CSCs)/poorly differentiated tumors whereas sNK cells target both CSCs/poorly-differentiated and well-differentiated tumors significantly higher than primary activated NK cells. Our in vivo studies in humanized-BLT mice showed that sNK cells alone or in combination with other cancer therapeutics prevented tumor growth and metastasis. In addition, sNK cells were able to increase IFN-γ secretion and cytotoxic function by the immune cells in bone marrow, spleen, gingiva, pancreas and peripheral blood. Furthermore, sNK cells were able to increase the expansion and function of CD8+ T cells both in in vitro and in vivo studies. Overall, our studies demonstrated that sNK cells alone or in combination with other cancer therapeutics were not only effective against eliminating aggressive cancers, but were also able to increase the expansion and function of CD8+ T cells to further target cancer cells, providing a successful approach to eradicate and cure cancer.

Image-matching digital macro-slide-a novel pathological examination method for microvascular invasion detection in hepatocellular carcinoma

Background

Microvascular invasion (MVI) is a prominent risk factor of postoperative recurrence for hepatocellular carcinoma (HCC). The MVI detection rate of conventional pathological examination approaches is relatively low and unsatisfactory.

Methods

By integrating pathological macro-slide with whole-mount slide imaging, we first created a novel pathological examination method called image-matching digital macro-slide (IDS). Surgical samples from eligible patients were collected to make IDS. The MVI detection rates, tumor recurrence rates and recurrence-free survival were compared among conventional 3-Point and 7-Point baseline sampling protocols and IDS. Additionally, biomarkers to recognize MVI false negative patients were probed via combining conventional pathological sampling protocols and IDS. Receiver operating characteristic curve (ROC) analysis was used to obtain the optimal cutoff of biomarkers to distinguish MVI false negative patients.

Results

The MVI detection rates were 21.98%, 32.97% and 63.74%, respectively, in 3-Point, 7-Point baseline sampling protocols and IDS (p < 0.001). Tumor recurrence rate of patients with MVI negative status in IDS (6.06%) was relatively lower than that of patients with MVI negative status in 3-Point (16.90%) and 7-Point (16.39%) sampling protocols. Alpha-fetoprotein (AFP) and protein induced by vitamin K absence or antagonist-II (PIVKA-II) were selected as potential biomarkers to distinguish MVI false negative patients.

Conclusions

Our study demonstrated that IDS can help enhance the detection rate of MVI in HCC and refine the prediction of HCC prognosis. Alpha-fetoprotein is identified as a suitable and robust biomarker to recognize MVI false-negative patients in conventional pathological protocols.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12072-022-10307-w.

Recurrent Hepatocellular Carcinoma After Liver Transplantation: Validation of a Pathologic Risk Score on Explanted Livers to Predict Recurrence

BACKGROUND

Recurrence of hepatocellular carcinoma (HCC) after liver transplantation is a major cause of morbidity and mortality. To date, there is no widely accepted pathologic assessment tool to predict HCC recurrence. In 2007, we developed a pathologic risk score that stratified patients into low, intermediate, or high risk for recurrence based on explant pathology. The aim of this study was to externally validate this risk score.

METHODS

We retrospectively evaluated 124 patients over a 10-year period who underwent liver transplantation for HCC. Using explanted pathology reports, each patient was stratified according to the pathologic risk score and followed over time for HCC recurrence.

RESULTS

Recurrence occurred in 15 patients (12%) after a mean follow-up of 25 months. Using the pathologic risk score, 10 (8%), 21 (17%), and 93 (75%) patients were stratified into high, intermediate, and low risk of recurrence, respectively. Among these risk groups, recurrence occurred in 50%, 28.5%, and 4.3% (P < .01) of patients, respectively. Using the optimal cutoff value ≤3.5, our risk score had a sensitivity of 80% and specificity of 79% with an area under the receiver operator characteristic curve of 0.8. Those with lower risk scores had higher recurrence-free survival (P < .0001).

CONCLUSIONS

Our pathologic risk score accurately risks stratified patients for HCC recurrence after liver transplant. It can be used to tailor surveillance strategies for those deemed to be at elevated risk for recurrence.

TLR9-1486C/T polymorphism is associated with hepatocellular carcinoma recurrence after liver transplantation

Aim: To determine whether TLR9 polymorphisms are associated with tumor recurrence after liver transplantation for hepatocellular carcinoma (HCC). Patients & methods: All patients who underwent liver transplantation, and had viable HCC in the explanted liver were included. TLR9-1237C/T and -1486C/T polymorphisms were analyzed by real-time PCR and melting curves analysis. Results: 20 of 159 patients (12.6%) developed post-transplant HCC recurrence. Tumors exceeding Milan criteria, moderately-to-poorly differentiated tumors and microvascular invasion on explants, and pretransplant α-fetoprotein level (all p < 0.01) were associated with an increased risk, while TLR9-1486TT genotype was associated with a decreased risk of HCC recurrence (p = 0.03). Conclusion: TLR9-1486C/T might help to preoperatively identify patients at low risk of post-transplant HCC recurrence.

Role of Allelic Imbalance in Predicting Hepatocellular Carcinoma (HCC) Recurrence Risk After Liver Transplant

Background

One of the most controversial problems for liver transplantation in patients affected by hepatocellular carcinoma (HCC) remains the lack of an oncologic staging system to predict cancer recurrence after liver transplantation (LT). We analyzed allelic imbalance (AI) in 19 microsatellites, and assessed the post-LT HCC recurrence risk.

Material/Methods

Seventy-one patients were included; 18 had tumor recurrence within 5 years post-transplant. Molecular analysis was done in the primary HCC and peripheral blood samples: a total of 19 microsatellites was used to assess AI. Specific AI was evaluated when outside of range value between 0.66 and 1.5. Based on data in the literature, we grouped the 19 microsatellites into 4 panels. We calculated the fractional allelic imbalance (FAI) to make comparisons between different panels including different subsets of microsatellites.

Results

We report that AI was associated with HCC recurrence in 3 main loci (D3S2303, D9S251, and D9S254). Tumor recurrence was associated only with 2 specific panels with 9 microsatellites previously reported to be associated with high risk for HCC recurrence. Our data show that fractional allelic imbalance (FAI) index has good negative ability to predict HCC recurrence (Panel 2: negative predictive value of 95%).

Conclusions

AI analysis could have prognostic value in risk management of HCC recurrence after LT, especially for early recurrence.

Noninvasive imaging of hepatocellular carcinoma: From diagnosis to prognosis

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and a major public health problem worldwide. Hepatocarcinogenesis is a complex multistep process at molecular, cellular, and histologic levels with key alterations that can be revealed by noninvasive imaging modalities. Therefore, imaging techniques play pivotal roles in the detection, characterization, staging, surveillance, and prognosis evaluation of HCC. Currently, ultrasound is the first-line imaging modality for screening and surveillance purposes. While based on conclusive enhancement patterns comprising arterial phase hyperenhancement and portal venous and/or delayed phase wash-out, contrast enhanced dynamic computed tomography and magnetic resonance imaging (MRI) are the diagnostic tools for HCC without requirements for histopathologic confirmation. Functional MRI techniques, including diffusion-weighted imaging, MRI with hepatobiliary contrast agents, perfusion imaging, and magnetic resonance elastography, show promise in providing further important information regarding tumor biological behaviors. In addition, evaluation of tumor imaging characteristics, including nodule size, margin, number, vascular invasion, and growth patterns, allows preoperative prediction of tumor microvascular invasion and patient prognosis. Therefore, the aim of this article is to review the current state-of-the-art and recent advances in the comprehensive noninvasive imaging evaluation of HCC. We also provide the basic key concepts of HCC development and an overview of the current practice guidelines.

Prognostic impact of surgical margin in patients with hepatocellular carcinoma: A meta-analysis

BACKGROUND

Surgical margin is an important prognostic factor in hepatectomy for patients with hepatocellular carcinoma (HCC). But the extent of surgical margins is still controversial. Our study was designed to systematically evaluate the prognosis of different width of resection margin.

METHODS

We conducted comprehensive searches of electronic databases including PubMed, MEDLINE, EMBASE, Cochrane, and the ISI Web of Science for relevant studies. A meta-analysis was performed by RevMan 5.3 software.

RESULTS

A total of 7 studies comprising 1932 patients were included. The patients with wider surgical margin were significantly higher than those with narrow surgical margin on 3-year overall survival (odds ratio [OR]: 1.58, 95% confidence interval (95% CI): 1.21-2.06, P = .0008), 5-year overall survival (OR: 1.76, 95% CI: 1.20-2.59, P = .004), 1-year disease-free survival (DFS)/recurrence-free survival (RFS) (OR: 1.43, 95% CI: 1.12-1.82, P = .005), 3-year DFS/RFS (OR: 1.66, 95% CI: 1.35-2.03, P < .00001), and 5-year DFS/RFS (OR: 1.69, 95% CI: 1.37-2.08, P < .00001). There was no significant difference in the 1-year overall survival rate for the 2 groups (OR: 1.24, 95% CI: 0.89-1.72, P = .20).

CONCLUSION

In comparison with the narrow surgical margin group (<1 cm), the wide surgical margin (≥1 cm) can significantly improve the prognosis in patients with HCC.

Liver transplantation recipients with nonalcoholic steatohepatitis have lower risk hepatocellular carcinoma

Liver transplantation (LT) is a well-established treatment for hepatocellular carcinoma (HCC) in carefully selected patients. Risk factors for tumors with poor prognostic features on explant have not been well described in a national cohort. We performed a retrospective cohort study of adult LT recipients with HCC transplanted from April 8, 2012 (when explant pathology in United Network for Organ Sharing [UNOS] became available) until September 30, 2014. We evaluated the association between listing diagnosis and other demographic factors with tumor features on explant using logistic regression. High-risk tumor features included the following: > 3 tumors, largest tumor > 5 cm, presence of vascular invasion, presence of metastases, and poor differentiation of tumor. In total, 3733 LT recipients with HCC who had complete explant data in UNOS were included. The median age was 60 years; 78% were male; and 68% were white. Of the primary non-HCC listing diagnoses, 2608 (70%) had hepatitis C virus (HCV); 271 (7%) had nonalcoholic steatohepatitis (NASH); 246 (7%) had alcoholic cirrhosis; and 189 (5%) had hepatitis B virus. Also, 1140 (31%) had evidence of ≥ 1 high-risk explant feature(s). The presence of ≥ 1 high-risk explant feature(s) was associated with HCC recurrence after transplant (odds ratio [OR], 5.00; P < 0.001). Compared with HCV-associated HCC transplant recipients, individuals with NASH had lower likelihood of high-risk explant features (OR, 0.71; P = 0.02) after adjusting for covariables. Women were more likely to have high-risk explant features (OR, 1.23; P = 0.04). Diabetes mellitus (DM) was not associated with high-risk explant features. In conclusion, LT recipients with NASH-associated HCC had fewer high-risk tumor features on explant compared with HCV-associated HCC, despite having higher rates of DM and other potential risk factors for the development of HCC. Women had a higher likelihood of high-risk tumor features. Further study is warranted whether these differences are due to disease-specific or sex-specific influences on tumor biology or due to selection criteria for transplant. Liver Transplantation 23 1015-1022 2017 AASLD.

Phase-contrast CT: Qualitative and Quantitative Evaluation of Capillarized Sinusoids and Trabecular Structure in Human Hepatocellular Carcinoma Tissues

RATIONALE AND OBJECTIVES

Capillarization of sinusoids and change of trabecular thickness are the main histologic features in hepatocellular carcinoma (HCC). Of particular interest are the three-dimensional (3D) visualization and quantitative evaluation of such alterations in the HCC progression. X-ray phase-contrast computed tomography (PCCT) is an emerging imaging method that provides excellent image contrast for soft tissues. This study aimed to explore the potential of in-line PCCT in microstructure imaging of capillarized sinusoids and trabecular structure in human HCC tissues and to quantitatively evaluate the alterations of those fine structures during the development of HCC.

MATERIALS AND METHODS

This project was designed as an ex vivo experimental study. The study was approved by the institutional review board, and informed consent was obtained from the patients. Eight human resected HCC tissue samples were imaged using in-line PCCT. After histologic processing, PCCT images and histopathologic data were matched. Fine structures in HCC tissues were revealed. Quantitative analyses of capillarized sinusoids (ie, percentage of sinusoidal area [PSA], sinusoidal volume) and trabecular structure (ie, trabecular thickness, surface-area-to-volume ratio [SA/V]) in low-grade (well or moderately differentiated) and high-grade (poorly differentiated) HCC groups were performed.

RESULTS

Using PCCT, the alterations of capillarized sinusoids and trabecular structure were clearly observed in 3D geometry, which was confirmed by the corresponding histologic sections. The 3D qualitative analyses of sinusoids in the high-grade HCC group were significantly different (P < 0.05) in PSA (7.8 ± 2.5%) and sinusoidal volume (2.9 ± 0.6 × 10⁷ µm³) from those in the low-grade HCC group (PSA, 12.9 ± 2.2%; sinusoidal volume, 2.4 ± 0.3 × 10⁷ µm³). Moreover, the 3D quantitative evaluation of the trabecular structure in the high-grade HCC group showed a significant change (P < 0.05) in the trabecular thickness (87.8 ± 15.6 µm) and SA/V (2.2 ± 1.3 × 10³ µm^-1) compared to the low-grade HCC group (trabecular thickness, 75.9 ± 7.1 µm; SA/V, 7.5 ± 1.3 × 10³ µm^-1).

CONCLUSIONS

This study provides insights into the 3D alterations of microstructures such as capillarized sinusoids and the trabecular structure at a micrometer level, which might allow for an improved understanding of the development of HCC.

Yes-associated protein expression is a predictive marker for recurrence of hepatocellular carcinoma after liver transplantation

PURPOSE

To explore the expression of Yes-associated protein (YAP) in hepatocellular carcinoma (HCC) patients, and assess its prognostic value to recurrence of HCC after liver transplantation (LT).

METHODS

Collected data of 105 consecutive patients undergoing LT for HCC were analyzed retrospectively. The immunohistochemistry was used to detect the expression of YAP, Mst1, Lats1/2, pYAP, pLats1/2 and pMst1/2 in tumor tissues. Contingency table and χ(2)-test were used to investigate the correlation between expression of YAP, Mst1, Lats1/2 and clinical characteristics. Univariate survival analysis and Multivariate Cox regression analysis were also performed to analyze the correlation of clinical and pathological factors with tumor recurrence after LT. The Kaplan-Meier method and log-rank test were used to analyze HCC-specific disease-free survival (DFS) rate.

RESULTS

Forty patients fulfilled Milan criteria with 1-, 2-, 3- and 5-years DFS of 86.7, 84.6, 84, 84%, respectively. The positive rates of YAP, Lats1/2, Mst1 in HCC were 51.4, 45.7, 64.8%, respectively. YAP expression in HCC tumors was significantly associated with tumor size (p = 0.041), venous infiltration (p = 0.002), AJCC tumor stage (p = 0.027). Lats1/2 expression was significantly associated with tumor size (p = 0.001) and AJCC tumor stage (p = 0.019). Mst1 expression was also significantly associated with tumor size (p = 0.042). HCC-specific DFS was significantly longer for patients with YAP negative expression compared with patients with YAP positive expression (1-, 2-, 3- and 5-years DFS of 71.7, 65.3, 65.3, 65.3 vs. 42.5, 36.6, 32.5, 30.4%, respectively, log-rank = 12.89, p < 0.001). Multivariate Cox regression analysis indicated that YAP expression (HR = 2.011, p = 0.020) in HCC was an independent prognostic factor for HCC-specific DFS after liver transplantation.

CONCLUSIONS

YAP is an independent prognostic marker for tumor recurrence for HCC patients after liver transplantation.

Global PROTOMAP profiling to search for biomarkers of early-recurrent hepatocellular carcinoma

This study used global protein expression profiling to search for biomarkers to predict early recurrent hepatocellular carcinoma (HCC). HCC tissues surgically resected from patients with or without recurrence within 2 years (early recurrent) after surgery were compared with adjacent nontumor tissue and with normal liver tissue. We used the PROTOMAP strategy for comparative profiling, which integrates denaturing polyacrylamide gel electrophoresis migratory rates and high-resolution, semiquantitative mass-spectrometry-based identification of in-gel-digested tryptic peptides. PROTOMAP allows examination of global changes in the size, topography, and abundance of proteins in complex tissue samples. This approach identified 8438 unique proteins from 45 708 nonredundant peptides and generated a proteome-wide map of changes in expression and proteolytic events potentially induced by intrinsic apoptotic/necrotic pathways. In the early recurrent HCC tissue, 87 proteins were differentially expressed (≥20-fold) relative to the other tissues, 46 of which were up-regulated or specifically proteolyzed and 41 of which were down-regulated. This data set consisted of proteins that fell into various functional categories, including signal transduction and cell organization and, notably, the major catalytic pathways responsible for liver function, such as the urea cycle and detoxification metabolism. We found that aberrant proteolysis appeared to occur frequently during recurrence of HCC in several key signal transducers, including STAT1 and δ-catenin. Further investigation of these proteins will facilitate the development of novel clinical applications.

Quantitative proteomic analysis identified paraoxonase 1 as a novel serum biomarker for microvascular invasion in hepatocellular carcinoma

This study aimed to identify serum biomarkers for microvascular invasion (MVI) in hepatocellular carcinoma (HCC). MVI is a histological sign of micrometastasis in the liver and is considered as one of the most powerful prognostic factors in HCC. The serum of HCC patients with different vascular invasion statuses was examined by iTRAQ-based proteomic profiling. The expression levels of 24 proteins were associated with the extent of vascular invasion in the pooled samples of 45 HCC cases. Western blot analyses in 90 HCC cases confirmed the correlation of the expression level of paraoxonase 1 (PON1) with the extent of vascular invasion. ELISA assays demonstrated the diagnostic utility of the PON1 level, with the area under curve values of 0.847 and 0.889 for the MVI and gross vascular invasion, respectively, relative to the patients without vascular invasion, in a cohort of 387 additional HCC cases. Immunohistochemistry revealed that PON1 expression in tumor cells was inversely correlated with the extent of vascular invasion in 200 additional HCC cases. In conclusion, using a proteomic approach, we found that serum PON1 was a novel diagnostic biomarker for MVI. The prognostic values of serum PON1 and its possible therapeutic applications are worth further investigation.

A systematic review of microvascular invasion in hepatocellular carcinoma: diagnostic and prognostic variability

Selected patients with hepatocellular carcinoma are candidates to receive potentially curative treatments, such as hepatic resection or liver transplantation, but nevertheless there is a high risk of tumor recurrence. Microvascular invasion is a histological feature of hepatocellular carcinoma related to aggressive biological behavior. We systematically reviewed 20 observational studies that addressed the prognostic impact of microvascular invasion, either after liver transplantation or resection. Outcomes were disease-free survival and overall survival. In liver transplantation, the presence of microvascular invasion shortened disease-free survival at 3 years (relative risk (RR)=3.41 [2.05-5.7]; five studies, n=651) and overall survival both at 3 years (RR=2.41 [1.72-3.37]; five studies, n=1,938) and 5 years (RR=2.29 [1.85-2.83]; six studies, n=2,003). After liver resection, microvascular invasion impacted disease-free survival at 3 and 5 years (RR=1.82 [1.61-2.07] and RR=1.51 [1.29-1.77]; four studies, n=1,501 for both comparisons). However inter/intraobserver variability in reporting and the lack of definition and grading of microvascular invasion has led to great heterogeneity in evaluating this histological feature in hepatocellular carcinoma. Thus, there is an urgent need to clarify this issue, because determining prognosis and response to therapy have become important in the current management of hepatocellular carcinoma. In this systematic review, we summarize the diagnostic and prognostic data concerning microvascular invasion in hepatocellular carcinoma and present a basis for consensus on its definition.

Non-cancerous prognostic factors of hepatocellular carcinoma after liver transplantation

PURPOSE

To explore non-cancerous factors that may be related with medium-term survival (24 months) after liver transplantation (LT) in this data from northeast Brazil.

METHODS

A cross-sectional study was carried out in patients who underwent deceased-donor orthotopic LT because hepatocellular carcinoma (HCC) at the University of Pernambuco, Brazil. Non-cancerous factors (i.e.: donor-, receptor-, surgery- and center-related variables) were explored as prognostic factors of medium-term survival using univariate and multivariate approachs.

RESULTS

Sixty-one patients were included for analysis. Their three, six, 12 and 24-month overall cumulative survivals were 88.5%, 80.3%, 73.8% and 65.6%, respectively. Our univariate analysis identified red blood cell transfusion (Exp[b]=1.26; p<0.01) and hepato-venous reconstruction technique (84.6% vs. 51.4%, p<0.01; respectively for piggyback and conventional approaches) as significantly related to post-LT survival. The multivariate analysis confirmed the hepato-venous reconstruction technique was an independent prognostic factor.

CONCLUSION

The piggyback technique was related to improved medium-term survival of hepatocellular carcinoma patients after liver transplantation in this northeast Brazilian sample.

Does the hepatocellular phase of gadobenate dimeglumine help to differentiate hepatocellular carcinoma in cirrhotic patients according to histological grade?

AIM

To assess the role of the hepatocellular phase on magnetic resonance imaging (MRI) following gadobenate in characterizing the grade of hepatocellular carcinoma (HCC) in cirrhotic patients.

MATERIALS AND METHODS

A retrospective review of the MRI database from October 2004 to February 2009, performed for this Institutional Review Board-approved and Health Insurance Portability and Accountability Act (HIPAA)-complaint study, revealed 237 cirrhotic patients with focal liver lesions. Patients who had both a hepatocellular phase after gadobenate and pathological confirmation of HCC were included. Forty-six patients with 73 HCC were analysed independently by two reviewers for signal characteristics. Absolute contrast-to-noise ratio (CNR) and enhancement ratio (ER) were calculated. Univariate analysis, stepwise logistic regression analysis, and receiver operating characteristic curves (ROC) were performed.

RESULTS

The mean age was 61.3 years (range 45 to 78 years). There were 11 females and 35 males, who had 22 well-differentiated (WD HCC), 35 moderately-differentiated (MD HCC), and 16 poorly-differentiated (PD HCC) hepatocellular carcinomas. On visual analysis of the hepatocellular phase, a hyperintense or isointense lesion had a sensitivity and specificity of 45% and 76%, respectively, for WD HCC. On quantitative analysis, the only significant predictor of the grade of HCC was the ER on the hepatocellular phase (p=0.019 and 0.001 for the two reviewers in logistic regression model). On ROC analysis, an ER of >13% was 47% sensitive and 89% specific in predicting WD HCC histology.

CONCLUSION

Although the hepatocellular phase of gadobenate may help to differentiate some cases of WD HCC from the more aggressive grades, there is overlap between the different grades on qualitative and quantitative analysis.

Molecular classification and clonal differentiation of hepatocellular carcinoma: the step forward for patient selection for liver transplantation

Liver transplantation is a successful treatment for hepatocellular carcinoma (HCC). However, advanced stages are not selected for transplant, based on the United Network for Organ Sharing selection criteria's. Nowadays, molecular biology-based techniques constitute an excellent option to better understand HCC origin differentiation and biological behavior. Moreover, microarray technology is a powerful tool to address a variety of tumor tissues at molecular level and is actively used for the discovery of biomarkers in cancer research. This article will discuss published data in the field of HCC origin differentiation and its potential impact on outcomes following liver transplantation. Although preliminary results are presented, these findings encourage the use of gene-expression profiling microarrays for studying HCC biology and behavior and ultimately optimizing treatment success.

Systematic review of outcome of downstaging hepatocellular cancer before liver transplantation in patients outside the Milan criteria

BACKGROUND

The aim of this systematic review was to assess the evidence on tumour downstaging before liver transplantation in patients with hepatocellular carcinoma (HCC) initially staged beyond the Milan criteria.

METHODS

MEDLINE (from 1952), Embase (from 1980) and the Cochrane Library were searched. The review included cohort studies that reported the outcomes of patients with HCC outside the Milan criteria who underwent downstaging before transplantation.

RESULTS

Eight studies met the inclusion criteria and included a total of 720 patients who underwent transplantation following downstaging after initial presentation with disease outside the Milan criteria. The rate of successful downstaging varied from 24 to 69 per cent of patients. Reported survival rates ranged from 82 to 100 per cent, 79 to 100 per cent and 54·6 to 94 per cent at 1, 3 and 5 years respectively. These were comparable with results for patients presenting within the Milan criteria.

CONCLUSION

Successful downstaging of HCC to within the Milan criteria is feasible in a proportion of patients. Absolute and disease-free survival rates in patients transplanted following downstaging are comparable to those in patients within the Milan criteria.

Pre-operative liver biopsy in cirrhotic patients with early hepatocellular carcinoma represents a safe and accurate diagnostic tool for tumour grading assessment

BACKGROUND & AIMS

Knowledge of pre-operative tumour grade is crucial in the management of hepatocellular carcinoma (HCC) because it can influence recurrence and survival after surgery. The accuracy of pre-operative needle core biopsy (NCB) in tumour grading has been assessed in only a few studies with conflicting results. Our aim was to determine the long-term safety and the overall accuracy of NCB in assessing tumour grading in subjects who had undergone liver resection for a single HCC.

METHODS

Eighty-one cirrhotic patients with HCC who had undergone NCB before liver resection were selected. Only patients with a single HCC and with at least a five-year-follow-up were included. Tumour grading was scored according to a modified Edmondson-Steiner classification: well/moderately (low grade) vs poorly-differentiated (high grade).

RESULTS

In the 81 patients with a solitary HCC (mean size 4.1 ± 2.3cm) tumour grade was correctly identified by NCB in 74 out of 81 (91.4%) HCCs. NCB overall sensitivity and specificity were 65% and 98.1%, respectively, with a PPV of 92% and an NPV of 91%. No major complications (in particular tumour seeding) were observed. The overall survival rates at 1, 3, and 5 years were 83%, 62%, and 44%, respectively; the recurrence rate after a 5-year-follow-up was 56.2% for low grade and 82.3% for high grade tumours (p<0.007).

CONCLUSIONS

Pre-operative NCB can be performed on early (<5 cm) HCC cirrhotic patients because it provides histologically useful information for HCC management with good accuracy and a low complication rate.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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