A multidisciplinary approach with immunotherapies for advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a highly aggressive disease that is usually diagnosed at an advanced stage. Advanced HCC has limited treatment options and often has a poor prognosis. For the past decade, tyrosine kinase inhibitors have been the only treatments approved for advanced HCC that have shown overall survival (OS) benefits; however, but their clinical efficacy has been limited. Recent trials have demonstrated promising advancements in survival outcomes through immunotherapy-based treatments, such as combinations of immune checkpoint inhibitors (ICIs) with other ICIs, antiangiogenic drugs, and locoregional therapies. The atezolizumab-bevacizumab and durvalumab-tremelimumab (STRIDE) regimen has significantly improved survival rates as a first-line treatment and has become the new standard of care. Therefore, combined treatments for advanced HCC can result in better treatment outcomes owing to their synergistic effects, which requires a multidisciplinary approach. Ongoing studies are examining other therapeutic innovations that can improve disease control and OS rates. Despite improvements in the treatment of advanced HCC, further studies on the optimal treatment selection and sequences, biomarker identification, combination approaches with other therapies, and development of novel immunotherapy agents are required. This review presents the current treatment options and clinical data of the ICI-based combination immunotherapies for advanced HCC from a multidisciplinary perspective.

Radiotherapy plus immune checkpoint inhibitor in prostate cancer

The immune checkpoint inhibitor (ICI) is a promising strategy for treating cancer. However, the efficiency of ICI monotherapy is limited, which could be mainly attributed to the tumor microenvironment of the "cold" tumor. Prostate cancer, a type of "cold" cancer, is the most common cancer affecting men's health. Radiotherapy is regarded as one of the most effective prostate cancer treatments. In the era of immune therapy, the enhanced antigen presentation and immune cell infiltration caused by radiotherapy might boost the therapeutic efficacy of ICI. Here, the rationale of radiotherapy combined with ICI was reviewed. Also, the scheme of radiotherapy combined with immune checkpoint blockades was suggested as a potential option to improve the outcome of patients with prostate cancer.

Current insights into the hepatic microenvironment and advances in immunotherapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and shows high global incidence and mortality rates. The liver is an immune-tolerated organ with a specific immune microenvironment that causes traditional therapeutic approaches to HCC, such as chemotherapy, radiotherapy, and molecular targeted therapy, to have limited efficacy. The dramatic advances in immuno-oncology in the past few decades have modified the paradigm of cancer therapy, ushering in the era of immunotherapy. Currently, despite the rapid integration of cancer immunotherapy into clinical practice, some patients still show no response to treatment. Therefore, a rational approach is to target the tumor microenvironment when developing the next generation of immunotherapy. This review aims to provide insights into the hepatic immune microenvironment in HCC and summarize the mechanisms of action and clinical usage of immunotherapeutic options for HCC, including immune checkpoint blockade, adoptive therapy, cytokine therapy, vaccine therapy, and oncolytic virus-based therapy.

Interventional Oncology and Immuno-Oncology: Current Challenges and Future Trends

Personalized cancer treatments help to deliver tailored and biologically driven therapies for cancer patients. Interventional oncology techniques are able to treat malignancies in a locoregional fashion, with a variety of mechanisms of action leading to tumor necrosis. Tumor destruction determines a great availability of tumor antigens that can be recognized by the immune system, potentially triggering an immune response. The advent of immunotherapy in cancer care, with the introduction of specific immune checkpoint inhibitors, has led to the investigation of the synergy of these drugs when used in combination with interventional oncology treatments. The aim of this paper is to review the most recent advances in the field of interventional oncology locoregional treatments and their interactions with immunotherapy.

Efficacy and Safety of PD-1/PD-L1 Inhibitors in Advanced Hepatocellular Carcinoma: A Systematic Review and Meta-analysis

INTRODUCTION

Programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) inhibitors have been increasingly employed for the treatment of various cancers in clinical practice. This study aimed to systematically evaluate the efficacy and safety of PD-1/PD-L1 inhibitors for advanced hepatocellular carcinoma (HCC).

METHODS

PubMed, EMBASE, Cochrane library, Web of Science, and Abstracts of American Society of Clinical Oncology proceedings databases were searched. Objective response rate (ORR), disease control rate (DCR), median progression-free survival (PFS), median overall survival (OS), and incidence of adverse events (AEs) and drug withdrawal were pooled. Odds ratio (OR) and hazard ratio (HR) were calculated to analyze the difference in the ORR, DCR, PFS, and OS between groups.

RESULTS

Among the 14,902 initially identified papers, 98 studies regarding use of PD-1/PD-L1 inhibitors in advanced HCC were included. Based on different criteria of response in solid tumors, the pooled ORR, DCR, and median PFS was 16-36%, 54-74%, and 4.5-6.8 months, respectively. The pooled median OS was 11.9 months. Compared to multitarget tyrosine kinase inhibitors (TKIs), PD-1/PD-L1 inhibitors monotherapy significantly increased ORR (OR 2.73, P < 0.00001) and OS (HR 0.97, P = 0.05), and PD-1/PD-L1 inhibitors combined with TKIs significantly increased ORR (OR 3.17, P < 0.00001), DCR (OR 2.44, P < 0.00001), PFS (HR 0.58, P < 0.00001), and OS (HR 0.58, P < 0.00001). The pooled incidence of all-grade AEs, grade ≥ 3 AEs, and drug withdrawal was 71%, 25%, and 7%, respectively.

CONCLUSION

On the basis of the present systematic review and meta-analysis, PD-1/PD-L1 inhibitors should be the preferred treatment choice for advanced HCC owing to their higher antitumor effect and improved outcomes.

An overview: Management of patients with advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has constituted a significant health burden worldwide, and patients with advanced HCC, which is stage C as defined by the Barcelona Clinic Liver Cancer staging system, have a poor overall survival of 6-8 months. Studies have indicated the significant survival benefit of treatment based on sorafenib, lenvatinib, or atezolizumab-bevacizumab with reliable safety. In addition, the combination of two or more molecularly targeted therapies (first- plus second-line) has become a hot topic recently and is now being extensively investigated in patients with advanced HCC. In addition, a few biomarkers have been investigated and found to predict drug susceptibility and prognosis, which provides an opportunity to evaluate the clinical benefits of current therapies. In addition, many therapies other than tyrosine kinase inhibitors that might have additional survival benefits when combined with other therapeutic modalities, including immunotherapy, transarterial chemoembolization, radiofrequency ablation, hepatectomy, and chemotherapy, have also been examined. This review provides an overview on the current understanding of disease management and summarizes current challenges with and future perspectives on advanced HCC.

Yttrium-90 Radioembolization: Current Indications and Outcomes

BACKGROUND

Radioembolization (RE) with 90Yttrium (Y90) has generally been used to treat patients with advanced disease. Recent data suggest, however, that RE is also safe and feasible to treat patients with early or intermediate stage disease. We herein review the current evidence regarding the use of RE with Y90 for patients with HCC.

METHODS

A comprehensive review of the literature was performed using MEDLINE/PubMed and Web of Science databases with a search end date of August 1, 2022.

RESULTS

Patients with HCC are often treated according to the BCLC staging system. Among patients with early-stage HCC (BCLC A), intermediate-stage HCC (BCLC B), and advanced-stage HCC (BCLC C), RE with Y90 has demonstrated promising results with comparable overall survival, time to disease progression, and radiological response compared with other standard of care treatment modalities. Moreover, Y90 RE can be used as a downstaging treatment modality for patients with advanced HCC who have a disease burden that is initially outside LT criteria. Radiation lobectomy (RL) has been described as a treatment modality with the intent of treating the ipsilateral liver that harbors the HCC, while also causing compensatory hypertrophy of the future liver remnant (FLR).

CONCLUSION

While initially considered as a palliative option for HCC patients, Y90 RE has emerged as an important part of the multi-modality care of patients with HCC across a wide spectrum of clinical indications.

Safety and efficacy of radiotherapy combined with lenvatinib plus PD-1 inhibitors as neo-adjuvant therapy in hepatocellular carcinoma with portal vein thrombus: protocol of an open-label, single-arm, prospective, multi-center phase I trial

Background

Surgical resection is a mainstay to treat hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) in east Asia. However, the postoperative recurrence rate is high. It is necessary to explore neo-adjuvant therapy to increase the surgical resection rate and improve overall survival. Evidence has shown that lenvatinib combined with PD-1 inhibitors is safe and effective in the treatment of advanced unresectable HCC. Radiotherapy is also an effective treatment method for PVTT and has a synergistic effect in combination with PD-1 inhibitors. Surgical resection after Lenvatinib and sintilimab combined with radiotherapy as a neoadjuvant treatment regimen may be a new exploration of HCC with PVTT, but there were not any reported.

Methods

This open-label, single-arm, prospective, multi-center Phase I trial will enroll 20 HCC patients with PVTT who have a resectable primary tumor and no extra-hepatic metastasis. Eligible patients will be given radiotherapy, 3Gy*10 fraction, and will receive lenvatinib 8-12mg once daily and sintilimab 200mg once every three weeks. Surgical resection will be performed 6-8 weeks after radiotherapy. The primary endpoint is safety (number of patients ≥3G TRAE) and the number of patients who complete pre-op treatment and proceed to surgery. The secondary study endpoints include Major Pathological Response (MPR), 1-year tumor recurrence-free rate, Objective Response Rate (ORR), Imaging-Pathology Concordance Rate (IPCR), PVTT regression rate, Median Overall Survival (OS) and Recurrence Free Survival (RFS).

Discussion

This trial may confirm that surgical resection following intensive neoadjuvant therapy can provide a safe and efficient regimen for BCLC stage C patients with PVTT.

Clinical trial registration

https://clinicaltrials.gov/, identifier (NCT05225116).

RESIRT: A Phase 1 Study of Selective Internal Radiation Therapy Using Yttrium-90 Resin Microspheres in Patients With Primary Renal Cell Carcinoma

INTRODUCTION

Selective internal radiation therapy (SIRT) is a potential treatment of primary renal cell carcinoma (RCC) deemed unsuitable for conventional therapy. RESIRT is the first-in-human study to evaluate safety and feasibility of SIRT for primary RCC.

PATIENTS AND METHODS

Patients with RCC, unsuitable for, or who declined conventional therapy, were eligible. A single transfemoral micro-catheter administration of yttrium-90 (Y-90) resin microspheres (SIR-Spheres) was delivered super selectively via the renal artery to the tumour at intended radiation doses of 75, 100, 150, 200, 300 Gy and a final cohort with a procedural endpoint of "imminent stasis," in a dose-escalation design. Post-SIRT follow-up was 12 months. Study endpoints included safety and toxicity 30-days and 12-months post-SIRT and tumour response (RECIST v1.1).

RESULTS

In total, 21 patients were enrolled, mean (SD) age was 75 (9.3) years, WHO performance status was 0 in 81%, 12 (57%) had stage 3 chronic kidney disease, and 7 (33%) had prior contralateral nephrectomy. Overall, 71% of patients completed 12 months of follow-up. Intended doses were delivered without any dose-limiting toxicity. Seventeen out of 21 (81%) patients experienced an adverse event (AE) from any cause within 30 days post-SIRT; all SIRT-related AEs were grade 1 to 2. Best overall tumour responses were partial response 1/21 (4.8%), stable disease 19/21 (90.5%) and progressive disease 1/21 (4.8%).

CONCLUSION

This study demonstrated good tolerability of SIRT at all dose levels including "imminent stasis" in treating primary tumours in RCC patients otherwise unsuitable for conventional therapy. SIRT with Y-90 resin microspheres may be a feasible treatment option for RCC.

Case report: Understanding the impact of persistent tissue-localization of SARS-CoV-2 on immune response activity via spatial transcriptomic analysis of two cancer patients with COVID-19 co-morbidity

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected half a billion people, including vulnerable populations such as cancer patients. While increasing evidence supports the persistence of SARS-CoV-2 months after a negative nasopharyngeal swab test, the effects on long-term immune memory and cancer treatment are unclear. In this report, we examined post-COVID-19 tissue-localized immune responses in a hepatocellular carcinoma (HCC) patient and a colorectal cancer (CRC) patient. Using spatial whole-transcriptomic analysis, we demonstrated spatial profiles consistent with a lymphocyte-associated SARS-CoV-2 response (based on two public COVID-19 gene sets) in the tumors and adjacent normal tissues, despite intra-tumor heterogeneity. The use of RNAscope and multiplex immunohistochemistry revealed that the spatial localization of B cells was significantly associated with lymphocyte-associated SARS-CoV-2 responses within the spatial transcriptomic (ST) niches showing the highest levels of virus. Furthermore, single-cell RNA sequencing data obtained from previous (CRC) or new (HCC) ex vivo stimulation experiments showed that patient-specific SARS-CoV-2 memory B cells were the main contributors to this positive association. Finally, we evaluated the spatial associations between SARS-CoV-2-induced immunological effects and immunotherapy-related anti-tumor immune responses. Immuno-predictive scores (IMPRES) revealed consistent positive spatial correlations between T cells/cytotoxic lymphocytes and the predicted immune checkpoint blockade (ICB) response, particularly in the HCC tissues. However, the positive spatial correlation between B cells and IMPRES score was restricted to the high-virus ST niche. In addition, tumor immune dysfunction and exclusion (TIDE) analysis revealed marked T cell dysfunction and inflammation, alongside low T cell exclusion and M2 tumor-associated macrophage infiltration. Our results provide in situ evidence of SARS-CoV-2-generated persistent immunological memory, which could not only provide tissue protection against reinfection but may also modulate the tumor microenvironment, favoring ICB responsiveness. As the number of cancer patients with COVID-19 comorbidity continues to rise, improved understanding of the long-term immune response induced by SARS-CoV-2 and its impact on cancer treatment is much needed.

Immune Checkpoint Inhibitors for Advanced Hepatocellular Carcinoma: Monotherapies and Combined Therapies

Hepatocellular carcinoma (HCC) is an important cause of cancer death and is considered the 3rd most lethal around the world. Hepatectomy, liver transplantation, and ablation therapy are considered curative treatments for early-stage HCC. Transarterial chemoembolization is the preferred therapy for intermediate stage HCC. Ssystemic therapy is recommended for advanced HCC. For more than a decade, sorafenib and lenvatinib were used as the first-line treatment for the advanced HCC. For the great success of immunotherapy in melanoma and lung cancer, some immune-based treatments, such as immune checkpoint inhibitors (ICIs), have been applied in the treatment of HCC. The anti-programmed cell death protein 1 (PD1) antibodies, including nivolumab and pembrolizumab, have been approved by the Food and Drug Administration for sorafenib-pretreated patients. Moreover, due to the results of durable antitumor responses attained from the phase 3 trials, atezolizumab in combination with bevacizumab is now the standard therapy for advanced HCC. Recently, there are a lot of clinical trials involving the ICIs, as monotherapy or combination therapy, with tyrosine kinase inhibitors, antiangiogenic drugs, cytotoxic agents, and locoregional treatments, providing a promising outcome for advanced HCC. Thus, this review summarized the role of ICIs for HCC patients with monotherapy or combination therapy. The success and failures of monotherapy and combination therapy involving ICIs have provided advanced insights into HCC treatment and led to novel avenues to improve therapy efficacy in HCC.

Clinical consensus statement: Selective internal radiation therapy with yttrium 90 resin microspheres for hepatocellular carcinoma in Asia

BACKGROUND

Hepatocellular carcinoma (HCC) is subject to different management approaches and guidelines according to Eastern and Western therapeutic algorithms. Use of selective internal radiation therapy (SIRT) with resin yttrium 90 microspheres for HCC has increased in Asia in recent years, without clearly defined indications for its optimal application. The objective of this systematic review and expert consensus statement is to provide guidance and perspectives on the use of SIRT among patients with HCC in Asia.

MATERIALS AND METHODS

A systematic literature review identified current publications on HCC management and SIRT recommendations. A group of 10 experts, representing stakeholder specialties and countries, convened between August 2020 and March 2021 and implemented a modified Delphi consensus approach to develop guidelines and indications for use of SIRT for HCC in Asia. Final recommendations were organized and adjudicated based on the level of evidence and strength of recommendation, per approaches outlined by the American College of Cardiology/American Heart Association and Oxford Centre for Evidence-Based Medicine.

RESULTS

The experts acknowledged a general lack of evidence relating to use of SIRT in Asia and identified as an unmet need the lack of phase 3 randomized trials comparing clinical outcomes and survival following SIRT versus other therapies for HCC. Through an iterative process, the expert group explored areas of clinical relevance and generated 31 guidance statements and a patient management algorithm that achieved consensus.

CONCLUSION

These recommendations aim to support clinicians in their decision-making and to help them identify and treat patients with HCC using SIRT in Asia. The recommendations also highlight areas in which further clinical trials are needed to define the role of SIRT in management of HCC among Asian populations.

Comparative assessment of standard and immune response criteria for evaluation of response to PD-1 monotherapy in unresectable HCC

PURPOSE

To assess response to programmed death-1 (PD-1) monotherapy (nivolumab) in hepatocellular carcinoma (HCC) patients using RECIST1.1, modified RECIST (mRECIST), and immune RECIST (iRECIST). A secondary objective was to identify clinicolaboratory and imaging variables predictive of progressive disease (PD) and overall survival (OS).

METHODS

Patients with HCC treated with nivolumab at a single institution from 5/2016 to 12/2019 with MRI or CT performed ≥ 4 weeks post treatment were retrospectively assessed. Patients who received concurrent locoregional, radiation, or other systemic therapies were excluded. Response was assessed by 2 observers in consensus using RECIST1.1, mRECIST, and iRECIST at 3/6/9/12-month time points. Time to progression (TTP) and OS were recorded. Clinicolaboratory and imaging variables were evaluated as predictors of PD and OS using uni-/multivariable and Cox regression analyses.

RESULTS

Fifty-eight patients (42M/16F) were included. 118 target lesions (TL) were identified before treatment. Baseline mean TL size was 49.1 ± 43.5 mm (range 10-189 mm) for RECIST1.1/iRECIST and 46.3 ± 42.3 mm (range 10-189 mm) for mRECIST. Objective response rate (ORR) was 21% for mRECIST/iRECIST/RECIST1.1, with no cases of pseudoprogression. Median OS and median TTP were 717 days and 127 days for RECIST1.1/mRECIST/iRECIST-iUPD (unconfirmed PD). Older age, MELD/Child-Pugh scores, AFP, prior transarterial radioembolization (TARE), and larger TL size were predictive of PD and/or poor OS using mRECIST/iRECIST. The strongest predictor of PD (HR = 2.49, 95% CI 1.29-4.81, p = 0.007) was TARE. The strongest predictor of poor OS was PD by mRECIST/iRECIST at 3 months (HR = 2.26, 95% CI 1.00-5.10, p = 0.05) with borderline significance.

CONCLUSION

Our results show ORR of 21%, equivalent for mRECIST, iRECIST, and RECIST1.1 in patients with advanced HCC clinically treated with nivolumab.

Efficacy of combined transarterial radioembolization and sorafenib in the treatment of hepatocarcinoma: A meta-analysis

BACKGROUND

Adjuvant sorafenib may further enhance the efficacy of transarterial radioembolization for the treatment of hepatocellular carcinoma.

AIMS

To evaluate the efficacy and safety of radioembolization plus sorafenib in hepatocellular carcinoma patients.

METHODS

With a literature search through October 2020, we identified 9 studies (632 patients). Primary outcome was overall survival. Results were expressed as pooled median, odds ratio, or hazard ratio and 95% confidence intervals.

RESULTS

Pooled overall survival after radioembolization plus sorafenib was 10.79 months (95% confidence interval 9.19-12.39) and it was longer in Barcelona Clinic Liver Cancer (BCLC) B (14.47 months, 9.07-19.86) as compared to BCLC C patients (10.22 months, 7.53-12.9). No difference between combined therapy versus radioembolization alone was observed in terms of overall survival (hazard ratio 1.07, 0.89-1.30). Pooled median progression-free survival was 6.32 months (5.68-6.98), with 1-year progression-free survival pooled rate of 38.5% (12.7%-44.2%). No difference in progression-free survival (hazard ratio 0.94, 0.79-1.12) between the two treatments was observed. Pooled rate of severe adverse events was 48.9% (26.7%-71.2%), again with no difference between the two treatment regimens (odds ratio 1.52, 0.15-15.02).

CONCLUSIONS

The association of sorafenib does not seem to prolong survival nor delay disease progression in patients treated with radioembolization.

Immunomodulation for hepatocellular carcinoma therapy: current challenges

PURPOSE OF REVIEW

The emergence of novel immunotherapies, such as immune-checkpoint inhibitors has changed the landscape of systemic cancer treatment. In hepatocellular carcinoma (HCC) patients, despite initial enthusiasm, the proportion of responders to immune-checkpoint inhibitors remains low. We provide a brief update of this rapidly evolving field, with specific focus on the development in the field of predictive factors and the immunomodulation induced by locoregional therapies.

RECENT FINDINGS

Even if the immune contexture of HCC before the treatment remains the most promising predictive marker for response to immunotherapies, recent findings show that the cause of HCC may have also a key role. Specific inflammatory mechanisms induced by NASH may result in limited efficacy of immunotherapy compared with viral HCC. Other recent findings showed that percutaneous ablations are responsible for intratumoral immune changes and systemic immune system activation that may help to prevent recurrence when combined with immunotherapies. In case of multifocal HCC, transarterial therapies (TACE and SIRT) may help to turn a cold tumor type to a hot tumor type and could be associated with immune-checkpoint inhibitors to improve outcomes.

SUMMARY

The future HCC management will focus on patient stratification for specific immunotherapies depending on the signature and cause of HCC and the best combined approaches in which locoregional therapies may play a pivotal role.

Strategies to Improve the Antitumor Effect of Immunotherapy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), one of the most fatal malignancies in the world, is usually diagnosed in advanced stages due to late symptom manifestation with very limited therapeutic options, which leads to ineffective intervention and dismal prognosis. For a decade, tyrosine kinase inhibitors (TKIs) have offered an overall survival (OS) benefit when used in a first-line (sorafenib and lenvatinib) and second-line setting (regorafenib and cabozantinib) in advanced HCC, while long-term response remains unsatisfactory due to the onset of primary or acquired resistance. Recently, immunotherapy has emerged as a promising therapy in the treatment of several solid tumors, such as melanoma and non-small cell lung cancer. Moreover, as the occurrence of HCC is associated with immune tolerance and immunosurveillance escape, there is a potent rationale for employing immunotherapy in HCC. However, immunotherapy monotherapy, mainly including immune checkpoint inhibitors (ICIs) that target checkpoints programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), and the cytotoxic T lymphocyte antigen-4 (CTLA-4), has a relatively low response rate. Thus, the multi-ICIs or the combination of immunotherapy with other therapies, like antiangiogenic drugs and locoregional therapies, has become a novel strategy to treat HCC. Combining different ICIs may have a synergistical effect attributed to the complementary effects of the two immune checkpoint pathways (CTLA-4 and PD-1/PD-L1 pathways). The incorporation of antiangiogenic drugs in ICIs can enhance antitumor immune responses via synergistically regulating the vasculature and the immune microenvironment of tumor. In addition, locoregional treatments can improve antitumor immunity by releasing the neoplasm antigens from killed tumor cells; in turn, this antitumor immune response can be intensified by immunotherapy. Therefore, the combination of locoregional treatments and immunotherapy may achieve greater efficacy through further synergistic effects for advanced HCC. This review aims to summarize the currently reported results and ongoing trials of the ICIs-based combination therapies for HCC to explore the rational combination strategies and further improve the survival of patients with HCC.

Combination therapies plus transarterial chemoembolization in hepatocellular carcinoma: a snapshot of clinical trial progress

INTRODUCTION

Unfortunately, some hepatocellular carcinoma (HCC) patients do not qualify for curative-intent treatments such as surgical resection or transplantation. Hence, locoregional treatments such as transarterial chemoembolization (TACE) remain instrumental in the treatment of HCC. Systemic therapy has improved over the past decade with the introduction of combination atezolizumab and bevacizumab as the new standard of care for advanced disease. These new therapies are currently under investigation in combination with TACE.

AREA COVERED

Combination therapies with TACE including systemic therapies, locoregional therapies, and immunotherapies are reviewed.

EXPERT OPINION

There has been limited progress in the management of advanced and intermediate HCC. Recent advances in the management of advanced disease with systemic therapy could be beneficial in combination with TACE for the treatment of intermediate stage disease. Immune based therapies are potentially beneficial in combination with TACE because TACE may produce increased antigen release and immune recognition.

Advances in locoregional therapy for hepatocellular carcinoma combined with immunotherapy and targeted therapy

Locoregional therapies (LRTs) of hepatocellular carcinoma (HCC) represented by ablation and TACE has become the main means for the clinical treatment of unresectable HCC. Among these, TACE is used throughout the stage Ib to IIIb of HCC treatment. In recent years, immunotherapy led by immune checkpoint inhibitors has become a hot direction in clinical research. At the same time, targeted drugs such as Sorafenib and Apatinib have played an important role in the treatment and complementary therapy of advanced HCC, and their clinical application has been quite mature. HCC is the sixth most common malignant tumor in the world. When it comes to its treatment, different therapies have different indications, and their individual efficacies are not satisfactory, which makes the exploration of the use of combination therapy in HCC treatment become a new trend. In this paper, the status of the three therapies and the progress of their combined application are briefly reviewed.

Emerging Trends in the Treatment of Advanced Hepatocellular Carcinoma: A Radiological Perspective

This is a narrative review of various treatment modalities for advanced hepatocellular carcinoma (HCC), with a focus on recent updates in radiological treatments, as well as novel treatment concepts related to immune checkpoint inhibitors and combination therapies with locoregional treatments. Interventional radiologists have made efforts toward developing alternative and/or combination treatments for first-line systemic treatment of patients with advanced HCC. Locoregional treatments with or without systemic therapy may be considered in the selected patients. Various treatment modalities for advanced HCC are emerging, and several randomized controlled trials, including those of combination treatments with immunotherapy, are ongoing.

Treatment of Hepatocellular Carcinoma with Immune Checkpoint Inhibitors and Applicability of First-Line Atezolizumab/Bevacizumab in a Real-Life Setting

Immune checkpoint inhibitors (ICIs) are the new frontier for the treatment of advanced hepatocellular carcinoma (HCC). Since the first trial with tremelimumab, a cytotoxic T-lymphocyte-associated protein 4 inhibitor, increasing evidence has confirmed that these drugs can significantly extend the survival of patients with advanced hepatocellular carcinoma (HCC). As a matter of fact, the overall survival and objective response rates reported in patients with advanced HCC treated with ICIs are the highest ever reported in the second-line setting and, most recently, the combination of the anti-programmed death ligand protein-1 atezolizumab with bevacizumab-an anti-vascular endothelial growth factor monoclonal antibody-demonstrated superiority to sorafenib in a Phase III randomized clinical trial. Therefore, this regimen has been approved in several countries as first-line treatment for advanced HCC and is soon expected to be widely used in clinical practice. However, despite the promising results of trials exploring ICIs alone or in combination with other agents, there are still some critical issues to deal with to optimize the prognosis of advanced HCC patients. For instance, the actual proportion of patients who are deemed eligible for ICIs in the real-life ranges from 10% to 20% in the first-line setting, and is even lower in the second-line scenario. Moreover, long-term data regarding the safety of ICIs in the population of patients with cirrhosis and impaired liver function are lacking. Lastly, no biomarkers have been identified to predict response, and thus to help clinicians to individually tailor treatment. This review aimed to summarize the state of the art immunotherapy in HCC and, by analyzing a large, multicenter cohort of Italian patients with HCC, to assess the potential applicability of the combination of atezolizumab/bevacizumab in the real-life setting.

Clinical Trials of Immune Checkpoint Inhibitors in Hepatocellular Carcinoma

Introduction: Several immune checkpoint inhibitors (CPIs) are under clinical development in hepatocellular carcinoma (HCC) and the field is advancing rapidly. In this comprehensive review, we discuss published results and report on ongoing clinical trials. Methods: A literature search was carried out using PubMed and EMBASE; data reported at international meetings and clinicaltrials.gov were included as well. The search was updated 5 March 2021. We evaluated studies with monotherapy CPI's, combinations of CPI's and combinations of CPI's with other treatment modalities separately. Only studies with at least 10 included patients were considered. Results: We identified 2649 records published in the English language literature. After review, 29 studies remained, including 12 studies with preliminary data only. The obtained overall response rate of PD-1/PDL-1 monotherapy in phase II studies in the second-line setting was 15-20% with disease control in approximately 60% of patients. The responses were of long duration in a subset of patients. Furthermore, the safety profiles were manageable. However, a phase III study comparing nivolumab with sorafenib in the first-line setting and a phase III study evaluating pembrolizumab versus best supportive care in the second-line setting did not meet their prespecified endpoints. More recently, a phase I/II study of nivolumab and ipilimumab has resulted in a response rate of approximately 30% with a median OS of 22 months in the second-line setting. Multiple trials have been initiated to evaluate CPIs in combination with molecularly targeted drugs, especially anti-angiogenic drugs or local therapy. A phase III study investigating atezolizumab plus bevacizumab versus sorafenib in the first-line setting showed significantly increased survival in the combination arm. Conclusions: The combination of atezolizumab and bevacizumab represents a new standard of care in the first-line setting for fit patients with preserved liver function. CPIs can produce durable tumor remission and induce long-standing anti-tumor immunity in a subgroup of patients with advanced HCC. Although phase III trials of CPI monotherapy have been negative, the combination of PD-1/PD-L1 inhibitors with other anti-angiogenic drugs, CTLA-4 inhibitors or other modalities may result in new treatment options for patients with HCC. Research on predictive biomarkers is crucial for further development of CPIs in HCC.

Safety of PD-1/PD-L1 Inhibitors Combined With Palliative Radiotherapy and Anti-Angiogenic Therapy in Advanced Hepatocellular Carcinoma

Background

Previous studies have explored cancer immunotherapy with radiotherapy or anti-angiogenic therapy, but no trials have reported a triple therapy approach. This study aimed to investigate safety and clinical outcome of PD-1/PD-L1 inhibitors combined with palliative radiotherapy and targeted angiogenesis therapy in hepatocellular carcinoma (HCC) of Barcelona Clinic Liver Cancer (BCLC) stage C.

Methods

Consecutive patients (n=16) treated with PD-1/PD-L1 inhibitors combined with radiotherapy and anti-angiogenic therapy in a bi-institutional cohort between July 2017 and December 2020 were retrospectively included. Radiotherapy was conducted within 14 days of the first administration of immunotherapy. The primary endpoint was treatment-related adverse event (TRAE).

Results

The median follow-up was 383 days. Fifteen patients (93.8%) experienced at least 1 TRAE. The most common TRAEs of any grade were rash (25%), diarrhea (25%), aspartate aminotransferase increase (18.8%), alanine transaminase increase (18.8%), decreased appetite (18.8%), and fatigue (18.8%). Grade 3/4 TRAEs occurred in 4 patients (25%) and finally led to treatment interruption. No patient death was attributed to treatment. No specific events were responsible for the addition of radiotherapy. Six patients showed partial response, 7 showed stable disease, and 2 showed progressive disease. The objective response rate and disease control rate were 40.0% (95% CI 16.3%-67.7%) and 86.7% (95% CI 59.5%-98.3%), respectively. Moreover, the median progression-free survival was 140 days. Patients had a median overall survival of 637 days, and the estimated rates of survival at 6 and 12 months were 92.3% and 75.5%, respectively.

Conclusion

PD-1/PD-L1 inhibitors combined with palliative radiotherapy and anti-angiogenic therapy appear to be safe, with no unexpected adverse events. Additional studies exploring the clinical benefit are warranted.

In Situ Vaccination as a Strategy to Modulate the Immune Microenvironment of Hepatocellular Carcinoma

Hepatocellular Carcinoma (HCC) is a highly prevalent malignancy that develops in patients with chronic liver diseases and dysregulated systemic and hepatic immunity. The tumor microenvironment (TME) contains tumor-associated macrophages (TAM), cancer-associated fibroblasts (CAF), regulatory T cells (Treg) and myeloid-derived suppressor cells (MDSC) and is central to mediating immune evasion and resistance to therapy. The interplay between these cells types often leads to insufficient antigen presentation, preventing effective anti-tumor immune responses. In situ vaccines harness the tumor as the source of antigens and implement sequential immunomodulation to generate systemic and lasting antitumor immunity. Thus, in situ vaccines hold the promise to induce a switch from an immunosuppressive environment where HCC cells evade antigen presentation and suppress T cell responses towards an immunostimulatory environment enriched for activated cytotoxic cells. Pivotal steps of in situ vaccination include the induction of immunogenic cell death of tumor cells, a recruitment of antigen-presenting cells with a focus on dendritic cells, their loading and maturation and a subsequent cross-priming of CD8+ T cells to ensure cytotoxic activity against tumor cells. Several in situ vaccine approaches have been suggested, with vaccine regimens including oncolytic viruses, Flt3L, GM-CSF and TLR agonists. Moreover, combinations with checkpoint inhibitors have been suggested in HCC and other tumor entities. This review will give an overview of various in situ vaccine strategies for HCC, highlighting the potentials and pitfalls of in situ vaccines to treat liver cancer.

Locoregional therapy in hepatocellular carcinoma: when to start and when to stop and when to revisit

With increasing therapeutic options available for advanced hepatocellular carcinoma (HCC), the timing and sequencing of locoregional and systemic therapy need to be re-examined. This is especially so for patients with intermediate HCC, so as to optimize responses while preserving liver reserves, and in so allowing our patients to achieve the best survival outcomes possible.

Recent Advances and Future Prospects in Immune Checkpoint (ICI)-Based Combination Therapy for Advanced HCC

Advanced, unresectable hepatocellular carcinoma has a dismal outcome. Multiple immune checkpoint inhibitors (ICIs) targeting the programmed-cell death 1 pathway (PD-1/L1) have been approved for the treatment of advanced HCC. However, outcomes remain undesirable and unpredictable on a patient-to-patient basis. The combination of anti-PD-1/L1 with alternative agents, chiefly cytotoxic T-lymphocyte antigen-4 (CTLA-4) ICIs or agents targeting other oncogenic pathways such as the vascular endothelial growth factor (VEGF) pathway and the c-MET pathway, has, in addition to the benefit of directly targeting alterative oncogenic pathways, in vitro evidence of synergism through altering the genomic and function signatures of T cells and expression of immune checkpoints. Several trials have been completed or are underway evaluating such combinations. Finally, studies utilizing transcriptomics and organoids are underway to establish biomarkers to predict ICI response. This review aims to discuss the biological rationale and clinical advances in ICI-based combinations in HCCs, as well as the progress and prospects of the search for the aforementioned biomarkers in ICI treatment of HCC.

The Evolving Landscape of Checkpoint Inhibitor Combination Therapy in the Treatment of Advanced Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers and a main cause of cancer-associated death worldwide. Even with the successful launch of sorafenib for the clinical treatment of HCC in 2007, the long-term survival for patients with HCC is still suboptimal, largely due to the occurrence of primary or acquired drug resistance. With an improved understanding of the molecular pathophysiology and tumor heterogeneity of HCC, therapeutic options have been evolving rapidly in recent years. While lenvatinib, cabozantinib, regorafenib, and the monoclonal antibody ramucirumab, as well as the immune checkpoint inhibitors (ICIs) atezolizumab, nivolumab, and pembrolizumab, have all shown promise in clinical trials, ICIs, especially when administered in combination with molecular-targeted drugs or cytotoxic drugs, have drawn increased attention. Recently, ample relevant clinical studies have surfaced, particularly related to the use of ICIs and exploring the therapeutic potential of ICI combination strategies. A more thorough knowledge of novel treatment strategies should help in decision making for advanced HCC therapy. The present review summarizes the mechanisms of HCC tumorigenesis, relevant trial results for approved HCC therapies, future perspectives, and major challenges for the overall treatment of HCC.

Immune Checkpoint Inhibitors in the Treatment of HCC

Hepatocellular carcinoma (HCC) is the typical inflammation-induced neoplasia. It often prospers where a chronic liver disease persists, thus leading a strong rationale for immune therapy. Several immune-based treatments, including immune checkpoint inhibitors (ICI), cytokines, adoptive cell transfer, and vaccines, have been tested in the treatment of HCC. In this review, we summarize the role of the ICI in HCC patients in various sets of treatment. As for advanced HCC, the anti-Programmed cell Death protein 1 (PD1) antibodies and the anti-Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) antibodies have been examined in patients with enthusiastic results in phase I-II-III studies. Overall, this led the Food and Drug Administration (FDA) to approve pembrolizumab, nivolumab, and nivolumab + ipilimumab in the second-line setting. The anti- Programmed Death-Ligand 1 (PDL-1) antibodies have also been evaluated. Thanks to the results obtained from phase III IMbrave study, atezolizumab + bevacizumab is now the standard of care in the first-line advanced setting of HCC. As for localized HCC, the putative immunological effect of locoregional therapies led to evaluate the combination strategy with ICI. This way, chemoembolization, ablation with radiofrequency, and radioembolization combined with ICI are currently under study. Likewise, the study of adjuvant immunotherapy following surgical resection is underway. In addition, the different ICI has been studied in combination with other ICI as well as with multikinase inhibitors and anti-angiogenesis monoclonal antibody. The evidence available suggests that combining systemic therapies and locoregional treatments with ICI may represent an effective strategy in this context.

Combinational Immunotherapy for Hepatocellular Carcinoma: Radiotherapy, Immune Checkpoint Blockade and Beyond

The systemic treatment landscape for advanced hepatocellular carcinoma (HCC) has experienced tremendous paradigm shift towards targeting tumor microenvironment (TME) following recent trials utilizing immune checkpoint blockade (ICB). However, limited success of ICB as monotherapy mandates the evaluation of combination strategies incorporating immunotherapy for improved clinical efficacy. Radiotherapy (RT) is an integral component in treatment of solid cancers, including HCC. Radiation mediates localized tumor killing and TME modification, thereby potentiating the action of ICB. Several preclinical and clinical studies have explored the efficacy of combining RT and ICB in HCC with promising outcomes. Greater efforts are required in discovery and understanding of novel combination strategies to maximize clinical benefit with tolerable adverse effects. This current review provides a comprehensive assessment of RT and ICB in HCC, their respective impact on TME, the rationale for their synergistic combination, as well as the current potential biomarkers available to predict clinical response. We also speculate on novel future strategies to further enhance the efficacy of this combination.