Anti-integrin αvβ6 autoantibodies in patients with primary sclerosing cholangitis

BACKGROUND

Patients with primary sclerosing cholangitis (PSC) possess autoantibodies against biliary epithelial cells. However, the target molecules remain unknown.

METHODS

The sera of patients with PSC and controls were subjected to enzyme-linked immunosorbent assays to detect autoantibodies using recombinant integrin proteins. Integrin αvβ6 expression in the bile duct tissues was examined using immunofluorescence. The blocking activity of the autoantibodies was examined using solid-phase binding assays.

RESULTS

Anti-integrin αvβ6 antibodies were detected in 49/55 (89.1%) patients with PSC and 5/150 (3.3%) controls (P < 0.001), with a sensitivity and specificity of 89.1% and 96.7%, respectively, for PSC diagnosis. When focusing on the presence or absence of IBD, the proportion of the positive antibodies in PSC with IBD was 97.2% (35/36) and that in PSC alone was 73.7% (14/19) (P = 0.008). Integrin αvβ6 was expressed in bile duct epithelial cells. Immunoglobulin (Ig)G from 15/33 patients with PSC blocked integrin αvβ6-fibronectin binding through an RGD (Arg-Gly-Asp) tripeptide motif.

CONCLUSIONS

Autoantibodies against integrin αvβ6 were detected in most patients with PSC; anti-integrin αvβ6 antibody may serve as a potential diagnostic biomarker for PSC.

Ultrasound-guided polidocanol foam sclerotherapy for symptomatic giant hepatic cyst: A single-center experience

AIM

Simple hepatic cysts are typically benign; however, when they are large and symptomatic, therapeutic intervention is required. We previously reported our initial experience with ultrasound (US)-guided polidocanol foam sclerotherapy in three patients with symptomatic giant hepatic cysts. In the present study, we examined the efficacy and safety of polidocanol foam sclerotherapy in a larger number of patients with long-term follow-up.

METHODS

Between May 2016 and April 2021, 15 patients with symptomatic giant hepatic cysts were referred to our hospital. All patients were prospectively included in the study and underwent US-guided polidocanol foam sclerotherapy.

RESULTS

The mean maximum diameter and estimated cyst volume were 128.4 mm (77-223 mm) and 922.3 ml (123.2-2797 ml), respectively. Polidocanol foam was successfully administered through an 8.5-Fr pigtail catheter in all patients. The percentages of cyst diameter/volume after 1-3 months, 3-6 months, 6 months-1 year, 1-2 years, and 2-4 years of sclerotherapy were 66.8%/36.5%, 48.1%/14.8%, 34.1%/6.9%, 28.2%/3.7%, and 26.2%/3.1%, respectively. During the follow-up period, there were no cases of symptom recurrence or need for additional treatment due to cyst re-growth. Six patients (40%) had fever, one had nausea, and one had right-sided chest pain, but none of these adverse events required prolonged hospitalization or readmission.

CONCLUSIONS

US-guided polidocanol foam sclerotherapy may be an effective and safe method for the treatment of symptomatic giant hepatic cysts.

Clinical and Molecular Basis of Hepatocellular Carcinoma after Hepatitis C Virus Eradication

Hepatocellular carcinoma (HCC) arises in the background of chronic liver diseases, including hepatitis and liver cirrhosis caused by hepatitis C virus (HCV) infection. It is well known that HCV eradication using antiviral drugs can efficiently inhibit hepatocarcinogenesis. Recent advances in and development of direct-acting antiviral (DAA) drugs has revolutionized the treatment of HCV infection, and the vast majority of HCV patients can achieve HCV eradication using DAAs. However, mounting evidence clearly indicates that HCC inevitably occurs in a subset of patients after successful viral eradication using DAA therapy. Cancer is a genetic disease, and the accumulation of genetic and epigenetic aberrations may cause hepatocarcinogenesis in chronically damaged liver, even after virus elimination. In this review, we highlight HCC development after HCV eradication and discuss the current understanding of the molecular mechanisms of tumorigenesis after virus elimination, focusing on the genetic and epigenetic background of chronically damaged liver tissues.

Expansion of gastric intestinal metaplasia with copy number aberrations contributes to field cancerization

Intestinal metaplasia (IM) is a risk factor for gastric cancer following infection with Helicobacter pylori. To explore the susceptibility of pure gastric IM to cancer development, we investigated genetic alterations in single IM gastric glands. We isolated 50 single IM or non-IM glands from the inflamed gastric mucosa of 11 patients with intramucosal gastric carcinoma (IGC) and 4 patients without IGC; nineteen single glands in the non-inflamed gastric mucosa of 11 individuals from our cohort and previous dataset were also included as controls. Whole exome sequencing of single glands revealed significantly higher accumulation of somatic mutations in various genes within IM glands compared with non-IM glands. Clonal ordering analysis showed that IM glands expanded to form clusters with shared mutations. Additionally, targeted-capture deep sequencing and copy number (CN) analyses were performed in 96 clustered IM or non-IM gastric glands from 26 patients with IGC. CN analyses were also performed on 41 IGC samples and the Cancer Genome Atlas-Stomach Adenocarcinoma datasets. These analyses revealed that polyclonally expanded IM commonly acquired copy number aberrations (CNA), including amplification of chromosomes 8, 20, and 2. A large portion of clustered IM glands typically consisted of common CNAs rather than other cancer-related mutations. Moreover, the CNA patterns of clustered IM glands were similar to those of IGC, indicative of precancerous conditions. Taken together, these findings suggest that, in the gastric mucosa inflamed with H. pylori infection, IM glands expand via acquisition of CNAs comparable to those of IGC, contributing to field cancerization.

Genetic Landscape of Multistep Hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is a major cause of cancer-related death worldwide. Although several targeted therapy agents are available for advanced HCC, their antitumor efficacy remains limited. As the complex genetic landscape of HCC would compromise the antitumor efficacy of targeted therapy, a deeper understanding of the genetic landscape of hepatocarcinogenesis is necessary. Recent comprehensive genetic analyses have revealed the driver genes of HCC, which accumulate during the multistage process of hepatocarcinogenesis, facilitating HCC genetic heterogeneity. In addition, as early genetic changes may represent key therapeutic targets, the genetic landscapes of early HCC and precancerous liver tissues have been characterized in recent years, in parallel with the advancement of next-generation sequencing analysis. In this review article, we first summarize the landscape of the liver cancer genome and its intratumor heterogeneity. We then introduce recent insight on early genetic alterations in hepatocarcinogenesis, especially those in early HCC and noncancerous liver tissues. Finally, we summarize the multistep accumulation of genetic aberrations throughout cancer progression and discuss the future perspective towards the clinical application of this genetic information.

Does immune checkpoint inhibitor exhibit limited efficacy against non-viral hepatocellular carcinoma?: A review of clinical trials

Immunotherapy with immune checkpoint inhibitors has been shown to be beneficial for cancers originating from various organs. In May 2020, combination therapy with anti-programmed death-ligand 1 antibody atezolizumab and anti-vascular endothelial growth factor (VEGF) antibody bevacizumab was approved as a novel first-line systemic therapy for hepatocellular carcinoma (HCC). The number of patients with HCC not caused by hepatitis virus infection (non-viral HCC), including non-alcoholic steatohepatitis (NASH)-related HCC, has been increasing in recent years. Recently, Pfister and colleagues reported that immune checkpoint inhibitors may exhibit limited efficacy against NASH-related HCC, based on basic research and clinical data. This review will discuss the mechanism of impaired tumor immune surveillance in NASH and analyze the results of previously published clinical trials of immune checkpoint inhibitors to investigate whether patients with non-viral HCC are less likely to benefit from immunotherapy with immune checkpoint inhibitors. Furthermore, we also discuss the possibility of enhancing the therapeutic effect of immune checkpoint inhibitors for NASH-related HCC by combining anti-VEGF agents.

Pretreatment Neutrophil-to-Lymphocyte Ratio as a Predictive Marker of Response to Atezolizumab Plus Bevacizumab for Hepatocellular Carcinoma

Background: Combination therapy with anti-programmed death-ligand 1 monoclonal antibody atezolizumab plus anti-vascular endothelial growth factor agent bevacizumab (Atezo/Bev) was approved in 2020 as a first-line treatment for unresectable hepatocellular carcinoma (HCC). Atezo/Bev therapy is relatively well tolerated; however, factors that can predict its response have not yet been reported. Thus, we aimed to investigate whether the pretreatment neutrophil-to-lymphocyte ratio (NLR) could predict the therapeutic response in patients with HCC treated with Atezo/Bev therapy. Methods: We analyzed the course of 40 patients with HCC who received Atezo/Bev therapy at our hospital and attempted to identify pretreatment factors that could predict response by comparing those who achieved disease control with those who did not. Results: The pretreatment NLR value in patients who achieved disease control was significantly lower than that in patients with disease progression (2.47 vs. 4.48, p = 0.013). Using the optimal NLR cut-off value for predicting response (3.21) determined by receiver operating characteristic curve analysis, patients with NLR ≤ 3.21 had significantly better progression-free survival than those with NLR > 3.21 (p < 0.0001), although there were no significant differences in liver function or tumor-related background factors between the two groups. Conclusions: The pretreatment NLR value may be a useful predictor of response to Atezo/Bev therapy for HCC.

A simplified method to quantitatively predict the effect of lenvatinib on hepatocellular carcinoma using contrast-enhanced ultrasound with perfluorobutane microbubbles

Contrast-enhanced computed tomography (CECT) is generally used to evaluate the response to treatment of hepatocellular carcinoma (HCC); however, CECT is unsuitable for the early prediction of therapeutic effects and frequent monitoring. We aimed to investigate the usefulness of our simplified method for the quantification of tumor vascularity using contrast-enhanced ultrasound (CEUS) with perfluorobutane microbubbles [Sonazoid^® (GE Healthcare, Oslo, Norway)] to predict the therapeutic effect of lenvatinib. Among the 13 patients studied, nine who had more than a 20% reduction in tumor vascularity within 2 weeks of starting treatment experienced complete response or partial response at 8-12 weeks as assessed by CECT. In contrast, three patients without reductions and one patient with only a slight decrease in tumor vascularity had a poor response to lenvatinib. Quantitative assessment of tumor vascularity by our simplified CEUS-based method could be a useful predictor of therapeutic responses to lenvatinib in patients with HCC.

Mac-2 binding protein glycosylation isomer predicts tolerability and clinical outcome of lenvatinib therapy for hepatocellular carcinoma

BACKGROUND

Many patients with hepatocellular carcinoma present with impaired hepatic function, which often requires interruption or withdrawal of lenvatinib due to associated adverse events. We aimed to identify pre-treatment predictors of tolerability and clinical outcome of lenvatinib therapy.

METHODS

Eighty patients who received lenvatinib at our institution between 2018 and 2020 were included in this study. We assessed essential factors associated with prolonged progression-free survival (PFS), using Cox proportional hazards model. We also investigated the correlation between the factor identified as contributing most to PFS and the relative dose intensity (RDI), response rate, and duration of treatment with lenvatinib.

RESULTS

Pre-treatment level of Mac-2-binding protein glycosylation isomer (M2BPGi) showed significant association with PFS (hazard ratio = 0.52, P = .0358). Low M2BPGi levels (<1.5) correlated significantly with longer PFS than higher levels (P = .0003). Patients with M2BPGi <1.5 achieved significantly higher RDI, objective response rate, and disease control rate, and maintained lenvatinib treatment for longer than those with baseline values ≥1.5. Patients with M2BPGi ≥1.5 had a higher incidence of adverse events such as fatigue and anorexia.

CONCLUSIONS

Baseline M2BPGi levels may predict the tolerability and treatment response to lenvatinib. Patients with high M2BPGi levels may less likely to benefit from lenvatinib therapy.

Laparoscopic liver resection versus percutaneous radiofrequency ablation for small hepatocellular carcinoma

BACKGROUND

Laparoscopic liver resection (LLR) and radiofrequency ablation (RFA) play central roles to treat early-stage hepatocellular carcinoma (HCC, ≤3 cm, 1-3 nodules, and no macrovascular involvement), although data are lacking regarding whether LLR or RFA is preferable. This study aimed to compare outcomes of both treatments for small HCCs.

METHODS

Treatment outcomes of small HCCs were compared between all the minor LLRs performed between 2005 and 2016 and RFAs performed between 2011 and 2016 at Kyoto University.

RESULTS

A total of 85 and 136 patients underwent LLR and RFA, respectively. Patients that underwent LLR had higher incidence of blood transfusions, complications, and longer hospital stay. Overall and disease-specific survival rates were similar between LLR and RFA; however, recurrence-free (49.2% vs. 22.1% at 3-year) and local recurrence-free survival rates (94.9% vs. 63.6% at 3-year) were higher after LLR. Multivariate analyses identified that multiple nodules and 65-year-old and above are predictors of disease-specific survival, and that RFA is a predictor of recurrence and local recurrence.

CONCLUSION

RFA is less invasive, although both LLR and RFA are safe and effective. LLR provides better local control with superior recurrence-free and local-recurrence free survival. These results help optimize treatment selection based on patient-specific factors.

Oncogenic transcriptomic profile is sustained in the liver after the eradication of the hepatitis C virus

Hepatocellular carcinoma (HCC) developing after hepatitis C virus (HCV) eradication is a serious clinical concern. However, molecular basis for the hepatocarcinogenesis after sustained virologic response (SVR) remains unclear. In this study, we aimed to unveil the transcriptomic profile of post-SVR liver tissues and explore the molecules associated with post-SVR carcinogenesis. We analysed 90 RNA sequencing datasets, consisting of non-cancerous liver tissues including 20 post-SVR, 40 HCV-positive and 7 normal livers, along with Huh7 cell line specimens before and after HCV infection and eradication. Comparative analysis demonstrated that cell cycle- and mitochondrial function-associated pathways were altered only in HCV-positive non-cancerous liver tissues, whereas some cancer-related pathways were up-regulated in the non-cancerous liver tissues of both post-SVR and HCV-positive cases. The persistent up-regulation of carcinogenesis-associated gene clusters after viral clearance was reconfirmed through in vitro experiments, of which, CYR61, associated with liver fibrosis and carcinogenesis in several cancer types, was the top enriched gene and co-expressed with cell proliferation-associated gene modules. To evaluate whether this molecule could be a predictor of hepatocarcinogenesis after cure of HCV infection, we also examined 127 sera from independent HCV-positive cohorts treated with direct-acting antivirals (DAAs), including 60 post-SVR-HCC patients, and found that the elevated serum Cyr61 was significantly associated with early carcinogenesis after receiving DAA therapy. In conclusion, some oncogenic transcriptomic profiles are sustained in liver tissues after HCV eradication, which might be a molecular basis for the liver cancer development even after viral clearance. Among them, up-regulated CYR61 could be a possible biomarker for post-SVR-HCC.

DNA methyltransferase 3B plays a protective role against hepatocarcinogenesis caused by chronic inflammation via maintaining mitochondrial homeostasis

Most hepatocellular carcinomas (HCCs) develop on the basis of chronic hepatitis, but the mechanism of epigenetic regulation in inflammatory hepatocarcinogenesis has yet to be elucidated. Among de novo DNA methyltransferases (DNMTs), DNMT3B has lately been reported to act specifically on actively transcribed genes, suggesting the possibility that it plays a role in the pathogenesis of cancer. We confirmed that DNMT3B isoforms lacking its catalytic domain were highly expressed in HCCs compared with non-tumorous liver tissue. To elucidate the role of DNMT3B in hepatocarcinogenesis, we generated a genetically engineered mouse model with hepatocyte-specific Dnmt3b deletion. The liver of the Dnmt3b-deficient mice exhibited an exacerbation of thioacetamide-induced hepatitis, progression of liver fibrosis and a higher incidence of HCC compared with the liver of the control mice. Whole-genome bisulfite sequencing verified a lower CG methylation level in the Dnmt3b-deficient liver, demonstrating differentially methylated regions throughout the genome. Transcriptome analysis revealed decreased expression of genes related to oxidative phosphorylation in the Dnmt3b-deficient liver. Moreover, primary hepatocytes isolated from the Dnmt3b-deficient mice showed reduced mitochondrial respiratory capacity, leading to the enhancement of oxidative stress in the liver tissue. Our findings suggest the protective role of DNMT3B against chronic inflammation and HCC development via maintaining mitochondrial homeostasis.

Current status of treatment with immune checkpoint inhibitors for gastrointestinal, hepatobiliary, and pancreatic cancers

The development of immune checkpoint inhibitors (ICIs) targeting cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed cell death protein ligand 1 (PD-L1) has revolutionized the treatment strategy in various types of cancers. In addition, recent studies have revealed that tumor microsatellite instability (MSI) status and tumor mutation burden (TMB) contribute significantly to the therapeutic response to anti-PD-1 monoclonal antibody (mAb), which led to an accelerated approval to pembrolizumab for the treatment of MSI-high or mismatch-repair-deficient solid tumors after conventional chemotherapies in 2017 and for the treatment of TMB-high solid tumors in 2020 by the United States Food and Drug Administration (FDA). In the field of gastrointestinal cancers, many clinical trials evaluating the safety and efficacy of various regimens such as ICI monotherapy, the combination of anti-CTLA-4 mAb and anti-PD-1/PD-L1 mAb, and combination of ICI and conventional chemotherapy or tyrosine kinase inhibitor have been reported or are in progress. This review summarizes MSI status and TMB in gastrointestinal, hepatobiliary, and pancreatic cancers, and provides the results of most relevant clinical trials evaluating ICIs. We also discuss the development of biomarkers required for improving the selection of patients with a high probability of benefiting from treatment with ICIs, and potential therapeutic strategies that could help to enhance anticancer responses of ICIs.

Hepatitis-associated Aplastic Anemia with Rapid Progression of Liver Fibrosis Due to Repeated Hepatitis

Hepatitis-associated aplastic anemia (HAAA) is a variant of acquired aplastic anemia and characterized by bone marrow failure that follows the development of acute hepatitis. We herein report a rare case of HAAA with rapid progression of liver fibrosis due to repeated hepatitis. A pathological examination of liver specimens revealed liver fibrosis progression over a short period. Immunosuppressive therapy with cyclosporine effectively cured both the pancytopenia and hepatitis. Our case suggests that the pathological examination of the liver tissue is useful for determining a treatment plan and that immunosuppressive therapy is a promising treatment for both aplastic anemia and persistent hepatitis.

Microsatellite instability and immune checkpoint inhibitors: toward precision medicine against gastrointestinal and hepatobiliary cancers

Recent innovations in the next-generation sequencing technologies have unveiled that the accumulation of genetic alterations results in the transformation of normal cells into cancer cells. Accurate and timely repair of DNA is, therefore, essential for maintaining genetic stability. Among various DNA repair pathways, the mismatch repair (MMR) pathway plays a pivotal role. MMR deficiency leads to a molecular feature of microsatellite instability (MSI) and predisposes to cancer. Recent studies revealed that MSI-high (MSI-H) or mismatch repair-deficient (dMMR) tumors, regardless of their primary site, have a promising response to immune checkpoint inhibitors (ICIs), leading to the approval of the anti-programmed cell death protein 1 monoclonal antibody pembrolizumab for the treatment of advanced or recurrent MSI-H/dMMR solid tumors that continue to progress after conventional chemotherapies. This new indication marks a paradigm shift in the therapeutic strategy of cancers; however, when considering the optimum indication for ICIs and their safe and effective usage, it is important for clinicians to understand the genetic and immunologic features of each tumor. In this review, we describe the molecular basis of the MMR pathway, diagnostics of MSI status, and the clinical importance of MSI status and the tumor mutation burden in developing therapeutic strategies against gastrointestinal and hepatobiliary malignancies.

Dose Intensity/Body Surface Area Ratio is a Novel Marker Useful for Predicting Response to Lenvatinib against Hepatocellular Carcinoma

Lenvatinib was recently approved as a novel first-line molecular targeted agent (MTA) for treating hepatocellular carcinoma (HCC). The importance of relative dose intensity (RDI) has been shown in the treatment of various types of cancers. However, RDI may not accurately reflect the treatment intensity of lenvatinib, as it is the first oral MTA where the dose is based on the patient's weight. We aimed to evaluate the utility of 2M-DBR (the delivered dose intensity/body surface area ratio at 60 days) by comparing the relationship between 2M-DBR, 2M-RDI (RDI at 60 days), and the therapeutic response. The therapeutic response to lenvatinib was evaluated in 45 patients who underwent computed tomography 8-12 weeks after treatment initiation. We also investigated the clinical factors associated with high 2M-DBR. The area under the receiver operating characteristic of 2M-DBR that predicts the response to lenvatinib was higher than that of 2M-RDI (0.8004 vs. 0.7778). Patients with high 2M-DBR achieved significantly better objective responses and disease control rates than those with low 2M-DBR (p < 0.0001 and 0.0008). Patients with high 2M-DBR experienced significantly longer progression-free survival (PFS) than those with low 2M-DBR (p = 0.0001), while there was no significant correlation between 2M-RDI levels and PFS (p = 0.2198). Patients who achieved higher levels of 2M-DBR had a significantly better modified ALBI grade (p = 0.0437), better CONUT score (p = 0.0222), and higher BTR (p = 0.0281). Multivariate analysis revealed that high 2M-DBR was the only significant factor associated with longer PFS. In conclusion, 2M-DBR could be an important factor that reflects treatment intensity and useful for predicting the response to lenvatinib against HCC, instead of 2M-RDI.

Association Between Preanalytical Factors and Tumor Mutational Burden Estimated by Next-Generation Sequencing-Based Multiplex Gene Panel Assay

BACKGROUND

Tumor mutational burden (TMB) measured via next-generation sequencing (NGS)-based gene panel is a promising biomarker for response to immune checkpoint inhibitors (ICIs) in solid tumors. However, little is known about the preanalytical factors that can affect the TMB score.

MATERIALS AND METHODS

Data of 199 patients with solid tumors who underwent multiplex NGS gene panel (OncoPrime), which was commercially provided by a Clinical Laboratory Improvement Amendments-licensed laboratory and covered 0.78 megabase (Mb) of capture size relevant to the TMB calculation, were reviewed. Associations between the TMB score and preanalytical factors, including sample DNA quality, sample type, sampling site, and storage period, were analyzed. Clinical outcomes of patients with a high TMB score (≥10 mutations per megabase) who received anti-programmed cell death protein 1 antibodies (n = 22) were also analyzed.

RESULTS

Low DNA library concentration (<5 nM), formalin-fixed paraffin-embedded tissue (FFPE), and the prolonged sample storage period (range, 0.9-58.1 months) correlated with a higher TMB score. After excluding low DNA library samples from the analysis, FFPE samples, but not the sample storage period, exhibited a marked correlation with a high TMB score. Of 22 patients with a high TMB score, we observed the partial response in 2 patients (9.1%).

CONCLUSION

Our results indicate that the TMB score estimated via NGS-based gene panel could be affected by the DNA library concentration and sample type. These factors could potentially increase the false-positive and/or artifactual variant calls. As each gene panel has its own pipeline for variant calling, it is unknown whether these factors have a significant effect in other platforms.

IMPLICATIONS FOR PRACTICE

A high tumor mutational burden score, as estimated via next-generation sequencing-based gene panel testing, should be carefully interpreted as it could be affected by the DNA library concentration and sample type.

Utility of ultrasound-guided liver tumor biopsy for next-generation sequencing-based clinical sequencing

AIM

Recent advances in next-generation sequencing (NGS) technologies allow for evaluation of genetic alterations in various cancer-related genes in daily clinical practice. Archival formalin-fixed paraffin-embedded (FFPE) tumor tissue is often used for NGS-based clinical sequencing assays; however, the success rate of NGS assays using archival FFPE tumor tissue is reported to be lower than that using fresh tumor tissue. We aimed to evaluate the feasibility and safety of ultrasound (US)-guided liver tumor biopsy for NGS-based multiplex gene assays.

METHODS

We compared the success rate of NGS assays between archival FFPE tumor tissues and US-guided liver tumor biopsy tissues, and summarized the treatment progress of the patients.

RESULTS

Next-generation sequencing assays using US-guided liver biopsy samples were successful in all patients (22/22), whereas the success rate with archival FFPE tumor tissue was 84.8% (151/178, P < 0.05). At least one potentially actionable genetic alteration was identified from the US-guided liver biopsy samples in 20 of 22 patients. Among the 18 patients with actionable genetic alterations targetable with drugs approved by the US Food and Drug Administration, eight initiated mutation-driven targeted therapies. Of these eight patients, four achieved partial response or stable disease for at least 4 months, and three were not assessable for response due to short exposure. There were no biopsy-related complications requiring additional treatment.

CONCLUSION

Our findings suggest that US-guided liver tumor biopsy is a useful and safe method for obtaining high-quality samples for NGS-based clinical sequencing. In cases with metastatic liver tumors, US-guided biopsy should be considered to provide accurate and optimal sequencing results for patients.

Combination of Mac-2 Binding Protein Glycosylation Isomer and Up-To-Seven Criteria as a Useful Predictor for Child-Pugh Grade Deterioration after Transarterial Chemoembolization for Hepatocellular Carcinoma

Transarterial chemoembolization (TACE) is the recommended first-line treatment for intermediate-stage hepatocellular carcinoma (HCC). In patients who became refractory to TACE, a treatment switch to tyrosine kinase inhibitors (TKIs) needs to be considered. However, TACE could worsen liver function, thereby narrowing the time window for a switch to TKIs because TKIs are recommended for patients with Child-Pugh grade A (CP-A). We investigated the factors associated with CP grade deterioration after TACE. Among patients who underwent TACE, 125 patients with CP-A were enrolled. The cumulative CP grade deterioration rates were 20.3%, 27.1%, and 41.4% at six months, one year, and two years, respectively. Multivariate analysis revealed that factors associated with CP grade deterioration included high Mac-2 binding protein glycosylation isomer (M2BPGi) levels (>2.00 cut-off index) and beyond the up-to-seven criteria. The cumulative CP grade deterioration rates of patients with high M2BPGi and beyond the up-to-seven criteria were 50.6% and 59.2% at six months and one year, respectively, which were significantly higher than for those in any other groups. The combination of M2BPGi and up-to-seven criteria could be a surrogate marker for predicting CP grade deterioration after TACE. In patients with intermediate-stage HCC, elevated M2BPGi levels, and beyond the up-to-seven criteria, an early treatment switch to TKIs should be considered to improve their prognosis.

Accelerated Progression of Hepatocellular Carcinoma during Immunosuppressive Therapy with Abatacept for Rheumatoid Arthritis

Abatacept, a cytotoxic T lymphocyte antigen-4 immunoglobulin recombinant fusion protein, is an immunosuppressive agent indicated for rheumatoid arthritis. Although no significant increase in malignancy has been reported in abatacept-treated patients, whether or not abatacept accelerates tumor progression in specific cancer types remains unclear. We herein report a 66-year-old woman who showed unusually rapid progression of hepatocellular carcinoma following abatacept therapy for rheumatoid arthritis. Abatacept was speculated to have accelerated her hepatocellular carcinoma progression in the setting of her preexisting risk factors: autoimmune hepatitis and long-term methotrexate use. We propose close tumor surveillance be performed during abatacept therapy, especially for high-risk patients.

Ultrasound-guided microfoam sclerotherapy with polidocanol for symptomatic giant hepatic cyst: Initial experience

AIM

In cases of symptomatic giant hepatic cysts, appropriate treatment is required to relieve symptoms. Ethanol, minocycline hydrochloride, and ethanolamine oleate have been conventionally used for ultrasound (US)-guided sclerotherapy. However, liquid sclerosing agents could mix with the residual fluid in the cyst and reduce their sclerotic effects. We carried out US-guided microfoam sclerotherapy using polidocanol for three patients and evaluated its efficacy and safety.

METHODS

Between May 2016 and March 2017, three female patients with symptomatic giant hepatic cysts were referred to our hospital. All of them were prospectively included in this study.

RESULTS

The maximum diameters of the hepatic cysts in the three patients were 92 × 89 × 86 mm, 155 × 119 × 140 mm, and 223 × 195 × 123 mm, respectively. Polidocanol microfoam was successfully administered through an 8.5-Fr pigtail catheter for all patients. One, two, and three microfoam sclerotherapy sessions were undertaken according to the initial cyst volume for cases 1, 2, and 3, respectively. The mean reduction rates of the cyst volume were 90.1% (85.5-98.9%) at 3 months, 96.3% (91.9-99.9%) at 6 months, and 99.5% (99.1-99.9%) at 9 months after treatment. No significant treatment-induced adverse effects were observed.

CONCLUSION

Ultrasound-guided microfoam sclerotherapy using polidocanol could be an effective and safe method for the treatment of symptomatic giant liver cysts.

Choledochoduodenal Fistula during Chemotherapy with Brentuximab Vedotin for Methotrexate-associated Lymphoproliferative Disorder

We herein report a patient with a history of rheumatoid arthritis treated with methotrexate, which caused methotrexate-associated lymphoproliferative disorder and obstructive jaundice due to an enlarged lymph node. The obstructive jaundice was treated with endoscopic biliary stenting. A histopathological examination revealed features of Hodgkin's lymphoma, and chemotherapy with brentuximab vedotin was administered. Cholangiography and duodenoscopy after four rounds of chemotherapy revealed a choledochoduodenal fistula that developed in response to chemotherapy. It should be noted that, in cases of lymphoma infiltrating the gastrointestinal wall, fistulae can occur because of rapid regression due to regimens comprising monoclonal antibodies, such as rituximab and brentuximab vedotin.

Novel approaches for molecular targeted therapy against hepatocellular carcinoma

Systemic chemotherapy using a multitargeted tyrosine kinase inhibitor is an established treatment for advanced-stage tumors in various organs. Comprehensive genomic analyses using next-generation sequencing technology revealed the intra- and intertumor heterogeneity of human hepatocellular carcinomas (HCCs), and provided evidence for the use of therapeutic agents effective against multiple targets in tumor cells. Recently, the efficacy and safety of a multitargeted tyrosine kinase inhibitor, lenvatinib, was confirmed by a randomized global phase III trial; thus, lenvatinib was approved as first-line therapy for HCC, providing a new therapeutic option for patients at an advanced stage. In this article, we introduce the application of molecular targeted therapy using lenvatinib and discuss future aspects of therapeutic options for advanced HCC.

Association of Mac-2-binding protein glycosylation isomer level with nutritional status in chronic liver disease

BACKGROUND AND AIM

Mac-2-binding protein glycosylation isomer (M2BPGi) was recently identified as a serum glycobiomarker for liver fibrosis. However, the relationship between M2BPGi and malnutrition in patients with chronic liver disease (CLD) is unknown. We aimed to evaluate whether M2BPGi could be a surrogate marker for malnutrition in patients with CLD.

METHODS

In total, 338 outpatients with CLD were enrolled (median age: 67 years). We evaluated the associations among liver fibrosis markers (M2BPGi, fibrosis-4 index, and aspartate aminotransferase-to-platelet count ratio index), Child-Pugh stages, and nutritional status markers.

RESULTS

The median value (range) of serum M2BPGi levels was 0.94 cut-off index (COI) (0.22-11.57) in chronic hepatitis and Child-Pugh A (n = 274), 4.775 COI (1.32-16.68) in Child-Pugh B (n = 46), and 11.37 COI (6.03-18.33) in Child-Pugh C (n = 18) (overall significance, P < 0.001). Serum M2BPGi levels showed a strong correlation with serum albumin concentration and controlling nutritional status score (rs  = -0.649, P < 0.001 and rs  = 0.671, P < 0.001, respectively). The correlations between M2BPGi and nutritional status markers were especially high in patients with hepatitis C virus infection and non-B non-C hepatitis and patients with hepatocellular carcinoma. Among the three fibrosis markers, M2BPGi yielded the highest area under the receiver operating characteristic curve (0.920) for predicting hypoalbuminemia at an optimal cut-off value of 2.41 (sensitivity, 87.3%; specificity, 87.6%; P < 0.001).

CONCLUSIONS

Serum M2BPGi levels are correlated with nutritional status markers in patients with CLD and could be a useful clinical marker of malnutrition.

Acute Anorectal Thrombophlebitis Caused by a Protein C Deficiency

A 46-year-old man visited the emergency department of our hospital with a 3-day history of anal pain, hemorrhaging, and a slight fever. He had previously been diagnosed with protein C deficiency and was prescribed dabigatran, a direct oral anticoagulant. Contrast-enhanced computed tomography showed severe rectal wall thickening with partial defect of enhancement. In addition, sigmoidoscopy revealed a dusky purplish swollen anorectal mucosa just above the dentate line. He was diagnosed with acute anorectal thrombophlebitis, and anticoagulant therapy with heparin was initiated. To our knowledge, this is the first case report of acute anorectal thrombophlebitis caused by protein C deficiency.

Utility of KRAS mutational analysis in the preoperative diagnosis of synchronous pancreatic cancer and intrahepatic cholangiocarcinoma: A case report

RATIONALE

It is often challenging to discriminate between intrahepatic cholangiocarcinoma (ICC) and metastatic liver tumors, especially when the hepatic tumor is small and of a mass-forming type.

PATIENT CONCERNS

We report a 69-year-old woman presented at our hospital with a small solid tumor in the head of the pancreas that was previously discovered during a medical checkup.

DIAGNOSES

The patient was diagnosed with synchronous pancreatic cancer and ICC.

INTERVENTIONS

The patient underwent clinical, histological, immunohistological, and KRAS mutational analysis.

OUTCOMES

Computed tomography revealed poorly enhanced small nodules in both the pancreatic head and liver. Biopsies of both nodules revealed adenocarcinoma; however, it was unclear whether the hepatic lesion was a metastasis of the pancreatic tumor or primary ICC. KRAS mutational analysis from FFPE biopsy samples revealed a discordance of mutation status between the tumors. Therefore, the patient was diagnosed with synchronous pancreatic cancer and ICC, whereupon she underwent hepatopancreatoduodenectomy.

LESSONS

KRAS mutational analysis of FFPE biopsy samples can be utilized for differentiating between ICC and metastatic liver tumor.

Proliferating EpCAM-Positive Ductal Cells in the Inflamed Liver Give Rise to Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) originates from regenerating liver cells with genetic alterations in chronically inflamed liver. Ductal cells and hepatocytes proliferate for liver regeneration, and proliferating ductal cells (PDC) derived from bile ductules have long been considered putative liver stem/progenitor cells and candidate cellular origins of HCC. The potential of PDC as tumor-originating cells, however, remains controversial in contrast to accumulating evidence that HCC originates from hepatocytes. Here, we demonstrate that PDCs expressing the established surface and cancer stem cell marker EpCAM give rise to HCC in inflamed liver. EpCAM-expressing PDCs were specifically labeled in newly developed Epcam^CreERT2 mice and traced in a chemically induced liver injury model. Stepwise accumulation of genetic alterations in EpCAM-positive cells was induced by the mutagenesis activity of activation-induced cytidine deaminase using conditional transgenic mice. Lineage-tracing experiments revealed that labeled PDC differentiated into cholangiocytes, but not into hepatocytes, in the chemically damaged liver. Nevertheless, EpCAM-positive PDC with genetic alterations gave rise to HCC after 8 months of chemical administration. PDC-derived HCC showed histologic characteristics of concomitant ductule-like structures resembling human cholangiolocellular carcinoma (CLC) and exhibited serial transitions from PDC-like CLC cells to hepatocyte-like HCC cells. The Wnt signaling pathway was specifically upregulated in the CLC components of PDC-derived HCC. Our findings provide direct experimental evidence that EpCAM-expressing PDC could be a cellular origin of HCC, suggesting the existence of stem/progenitor-derived hepatocarcinogenesis. Cancer Res; 77(22); 6131-43. ©2017 AACR.

Follicular lymphoma of the caecum resected endoscopically

Colorectal follicular lymphomas, primary or secondary, are rare. Magnifying endoscopy with narrow-band imaging is useful in the diagnosis of colorectal follicular lymphoma. In addition, immunohistochemistry is essential in differentiating follicular lymphoma cells from lymphoid follicle hyperplasia based on the presence of Bcl-2 expression. We herein report a rare case of follicular lymphoma of the caecum, presenting as a small polyp that was resected endoscopically.

Activation-Induced Cytidine Deaminase Contributes to Pancreatic Tumorigenesis by Inducing Tumor-Related Gene Mutations

Pancreatic ductal adenocarcinoma (PDAC) develops via an accumulation of various gene mutations. The mechanism underlying the mutations in PDAC development, however, is not fully understood. Recent insight into the close association between the mutation pattern of various cancers and specific mutagens led us to investigate the possible involvement of activation-induced cytidine deaminase (AID), a DNA editing enzyme, in pancreatic tumorigenesis. Our immunohistochemical findings revealed AID protein expression in human acinar ductal metaplasia, pancreatic intraepithelial neoplasia, and PDAC. Both the amount and intensity of the AID protein expression increased with the progression from precancerous to cancerous lesions in human PDAC tissues. To further assess the significance of ectopic epithelial AID expression in pancreatic tumorigenesis, we analyzed the phenotype of AID transgenic (AID Tg) mice. Consistent with our hypothesis that AID is involved in the mechanism of the mutations underlying pancreatic tumorigenesis, we found precancerous lesions developing in the pancreas of AID Tg mice. Using deep sequencing, we also detected Kras and c-Myc mutations in our analysis of the whole pancreas of AID Tg mice. In addition, Sanger sequencing confirmed the presence of Kras, c-Myc, and Smad4 mutations, with the typical mutational footprint of AID in precancerous lesions in AID Tg mice separated by laser capture microdissection. Taken together, our findings suggest that AID contributes to the development of pancreatic precancerous lesions by inducing tumor-related gene mutations. Our new mouse model without intentional manipulation of specific tumor-related genes provides a powerful system for analyzing the mutations involved in PDAC.

Leptin receptor somatic mutations are frequent in HCV-infected cirrhotic liver and associated with hepatocellular carcinoma

BACKGROUND & AIMS

Hepatocellular carcinoma develops in patients with chronic hepatitis or cirrhosis via a stepwise accumulation of various genetic alterations. To explore the genetic basis of development of hepatocellular carcinoma in hepatitis C virus (HCV)-associated chronic liver disease, we evaluated genetic variants that accumulate in nontumor cirrhotic liver.

METHODS

We determined the whole exome sequences of 7 tumors and background cirrhotic liver tissues from 4 patients with HCV infection. We then performed additional sequencing of selected exomes of mutated genes, identified by whole exome sequencing, and of representative tumor-related genes on samples from 22 cirrhotic livers with HCV infection. We performed in vitro and in vivo functional studies for one of the mutated genes.

RESULTS

Whole exome sequencing showed that somatic mutations accumulated in various genes in HCV-infected cirrhotic liver tissues. Among the identified genes, the leptin receptor gene (LEPR) was one of the most frequently mutated in tumor and nontumor cirrhotic liver tissue. Selected exome sequencing analyses detected LEPR mutations in 12 of 22 (54.5%) nontumorous cirrhotic livers. In vitro, 4 of 7 (57.1%) LEPR mutations found in cirrhotic livers reduced phosphorylation of STAT3 to inactivate LEPR-mediated signaling. Moreover, 40% of Lepr-deficient (C57BL/KsJ-db/db) mice developed liver tumors after administration of thioacetamide compared with none of the control mice.

CONCLUSIONS

Based on analysis of liver tissue samples from patients, somatic mutations accumulate in LEPR in cirrhotic liver with chronic HCV infection. These mutations could disrupt LEPR signaling and increase susceptibility to hepatocarcinogenesis.

Novel mouse models of hepatocarcinogenesis with stepwise accumulation of genetic alterations

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Various risk factors are involved in hepatocarcinogenesis. Among them, chronic inflammation, including chronic hepatitis and cirrhosis mainly caused by hepatitis B virus and/or hepatitis C virus infection, plays an important role in HCC development. On the other hand, comprehensive genetic analyses of HCC using whole genome and exome sequencing revealed that cancer cells possess a large number of somatic mutations, suggesting that a wide variety of genetic alterations and the resultant dysregulated molecular pathways contribute to the development of HCC. Activation-induced cytidine deaminase (AID) is a nucleotide-editing enzyme, and aberrant expression of AID induced by inflammatory responses contributes to hepatocarcinogenesis via the accumulation of genetic alterations in various tumor-related genes. Constitutive expression of AID in hepatocyte-lineage cells provides novel mouse models that recapitulate the tumorigenesis of human HCC through stepwise accumulation of genetic alterations.

Clinical characteristics of non-B non-C hepatocellular carcinoma: a single-center retrospective study

BACKGROUND/AIMS

To clarify risk factors and clinical features of both hepatitis B surface antigen and anti-HCV negative hepatocellular carcinoma (NBNC-HCC).

METHODS

HCC patients (n = 1,109) diagnosed at a single center were categorized based on the presence of serum hepatitis B surface antigen and HCVAb. Clinical characteristics of 127 NBNC-HCC patients were evaluated.

RESULTS

NBNC-HCC patients were stratified as those with alcoholic liver disease (ALD-HCC, n = 42) and alcohol-unrelated liver disease (non-ALD-HCC, n = 85). Compared with the ALD-HCC group, the non-ALD-HCC group had a higher prevalence of diabetes (p = 0.015), larger tumor size (p = 0.007), and higher tumor marker levels (p = 0.014). Liver function results were significantly worse in ALD-HCC than in non-ALD-HCC. Although the ALD-HCC group had a higher tendency toward recurrence than the non-ALD-HCC group, survival rates were similar between groups (p = 0.352).

CONCLUSION

Alcohol consumption was the most common etiologic factor for NBNC-HCC, and diabetes may be related to the development of HCC in non-ALD-HCC patients. Non-ALD-HCC tended to be diagnosed at a more advanced stage, whereas liver function was worse, and tumor recurrence rate was higher in ALD-HCC patients. Further examination of the risk factors and establishment of a precise surveillance system are necessary for early diagnosis and the development of curative therapies for NBNC-HCC.

Decrease in alpha-fetoprotein levels predicts reduced incidence of hepatocellular carcinoma in patients with hepatitis C virus infection receiving interferon therapy: a single center study

BACKGROUND

Increasing evidence suggests the efficacy of interferon therapy for hepatitis C in reducing the risk of hepatocellular carcinoma (HCC). The aim of this study was to identify predictive markers for the risk of HCC incidence in chronic hepatitis C patients receiving interferon therapy.

METHODS

A total of 382 patients were treated with standard interferon or pegylated interferon in combination with ribavirin for chronic hepatitis C in a single center and evaluated for variables predictive of HCC incidence.

RESULTS

Incidence rates of HCC after interferon therapy were 6.6% at 5 years and 13.4% at 8 years. Non-sustained virological response (non-SVR) to antiviral therapy was an independent predictor for incidence of HCC in the total study population. Among 197 non-SVR patients, independent predictive factors were an average alpha-fetoprotein (AFP) integration value ≥10 ng/mL and male gender. Even in patients whose AFP levels before interferon therapy were ≥10 ng/mL, reduction of average AFP integration value to <10 ng/mL by treatment was strongly associated with a reduced incidence of HCC. This was significant compared to patients with average AFP integration values of ≥10 ng/mL (P = 0.009).

CONCLUSIONS

Achieving sustained virological response (SVR) by interferon therapy reduces the incidence of HCC in hepatitis C patients treated with interferon. Among non-SVR patients, a decrease in the AFP integration value by interferon therapy closely correlates with reduced risk of HCC incidence after treatment.