Pembrolizumab for the Treatment of Hepatocellular Carcinoma

Hepatocellular Carcinoma and the Multifaceted Relationship with Its Microenvironment: Attacking the Hepatocellular Carcinoma Defensive Fortress

Hepatocellular carcinoma is a malignant tumor that originates from hepatocytes in an inflammatory substrate due to different degrees of liver fibrosis up to cirrhosis. In recent years, there has been growing interest in the role played by the complex interrelationship between hepatocellular carcinoma and its microenvironment, capable of influencing tumourigenesis, neoplastic growth, and its progression or even inhibition. The microenvironment is made up of an intricate network of mesenchymal cells, immune system cells, extracellular matrix, and growth factors, as well as proinflammatory cytokines and translocated bacterial products coming from the intestinal microenvironment via the enterohepatic circulation. The aim of this paper is to review the role of the HCC microenvironment and describe the possible implications in the choice of the most appropriate therapeutic scheme in the prediction of tumor response or resistance to currently applied treatments and in the possible development of future therapeutic perspectives, in order to circumvent resistance and break down the tumor's defensive fort.

Treatment Options for Hepatocellular Carcinoma Using Immunotherapy: Present and Future

Hepatocellular carcinoma (HCC) is a common cancer, and the body's immune responses greatly affect its progression and the prognosis of patients. Immunological suppression and the maintenance of self-tolerance in the tumor microenvironment are essential responses, and these form part of the theoretical foundations of immunotherapy. In this review, we first discuss the tumor microenvironment of HCC, describe immunosuppression in HCC, and review the major biomarkers used to track HCC progression and response to treatment. We then examine antibody-based therapies, with a focus on immune checkpoint inhibitors (ICIs), monoclonal antibodies that target key proteins in the immune response (programmed cell death protein 1, anti-cytotoxic T-lymphocyte associated protein 4, and programmed death-ligand 1) which have transformed the treatment of HCC and other cancers. ICIs may be used alone or in conjunction with various targeted therapies for patients with advanced HCC who are receiving first-line treatments or subsequent treatments. We also discuss the use of different cellular immunotherapies, including T cell receptor (TCR) T cell therapy and chimeric antigen receptor (CAR) T cell therapy. We then review the use of HCC vaccines, adjuvant immunotherapy, and oncolytic virotherapy, and describe the goals of future research in the development of treatments for HCC.

A change point-based analysis procedure for improving the success rate of decision-making in clinical trials with delayed treatment effects

A delayed treatment effect is a commonly observed phenomenon in tumor immunotherapy clinical trials. It can cause a loss of statistical power and complicate the interpretation of the analytical findings. This phenomenon also poses challenges for interim analysis in the context of phase II/III seamless design or group sequential design. It shows potential to lead researchers to make incorrect go/no-go decisions. Despite its significance, rare research has explored the impact of delayed treatment effects on the decision success rate of the interim analysis and the methods to compensate for this loss. In this study, we propose an analysis procedure based on change points for improving the decision success rate at the interim analysis in the presence of delayed treatment effects. This procedure primarily involves three steps: I. detecting and testing the number and locations of change points; II. estimating treatment efficacy; and III. making go/no-go decisions. Simulation results demonstrate that when there is a delayed treatment effect with a single change point, using the proposed analysis procedure significantly improves the decision success rate while controlling the type I error rate. Moreover, the proposed method exhibits very little disparity compared to the unadjusted method when the proportional hazards assumption holds. Therefore, the proposed analysis procedure provides a feasible approach for decision-making at the interim analysis when delayed treatment effects are present.

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.

Potential Predictive Biomarkers of Systemic Drug Therapy for Hepatocellular Carcinoma: Anticipated Usefulness in Clinical Practice

In the systemic drug treatment of hepatocellular carcinoma, only the tyrosine kinase inhibitor (TKI) sorafenib was available for a period. This was followed by the development of regorafenib as a second-line treatment after sorafenib, and then lenvatinib, a new TKI, proved non-inferiority to sorafenib and became available as a first-line treatment. Subsequently, cabozantinib, another TKI, was introduced as a second-line treatment, along with ramucirumab, the only drug proven to be predictive of therapeutic efficacy when AFP levels are >400 ng/mL. It is an anti-VEGF receptor antibody. More recently, immune checkpoint inhibitors have become the mainstay of systemic therapy and can now be used as a first-line standard treatment for HCC. However, the objective response rate for these drugs is currently only 30% to 40%, and there is a high incidence of side effects. Additionally, there are no practical biomarkers to predict their therapeutic effects. Therefore, this review provides an overview of extensive research conducted on potential HCC biomarkers from blood, tissue, or imaging information that can be used in practice to predict the therapeutic efficacy of systemic therapy before its initiation.

Unresectable Hepatocellular Carcinoma: A Review of New Advances with Focus on Targeted Therapy and Immunotherapy

With an expected incidence of more than 1 million cases by 2025, liver cancer remains a problem for world health. With over 90% of cases, hepatocellular carcinoma (HCC) is the most prevalent kind of liver cancer. In this review, we presented the range of experimental therapeutics for patients with advanced HCC, the successes and failures of new treatments, areas for future development, the evaluation of dose-limiting toxicity in different drugs, and the safety profile in patients with liver dysfunction related to the underlying chronic liver disease. In addition to the unmet demand for biomarkers to guide treatment decisions and the burgeoning fields of immunotherapy and systemic therapy in hepatocellular carcinoma, the development of old and new drugs, including their failures and current advancements, has been reviewed. This review aims to evaluate the updated optimal clinical treatment of unresectable hepatocellular carcinomas in clinical practice, mainly through targeted therapy. Although surgical treatment can significantly enhance the survival probability of early and intermediate-stage patients, it is unsuitable for most HCC patients due to a lack of donors. Due to their severe toxicity, the few first-line anti-HCC drugs, such as sorafenib, are often reserved for advanced HCC patients for whom other therapies have failed. The second-line drugs are usually alternatives for patients with intolerance or resistance. Consequently, the ongoing growth of possible preclinical drugs and studies on miRNAs, lncRNAs, and numerous other signaling pathway targets for developing novel drugs may introduce additional treatment prospects for HCC.

Lenvatinib plus anti-PD-1 therapy represents a feasible conversion resection strategy for patients with initially unresectable hepatocellular carcinoma: A retrospective study

Purpose

We aimed to investigate the feasibility of lenvatinib plus anti-PD-1 therapy as a conversion therapy for initially unresectable hepatocellular carcinoma (HCC).

Methods

Patients with initially unresectable HCC who received combined lenvatinib and anti-PD-1 antibody between May 2020 and Jan 2022 in Zhongshan Hospital were retrospectively analyzed. Tumor response and resectability were assessed by imaging every two months according to RECIST version 1.1 and modified RECIST (mRECIST) criteria.

Results

A total of 107 patients were enrolled. 30 (28%) of them received conversion surgery within 90.5 (range: 53-456) days after the initiation of lenvatinib plus anti-PD-1 therapy. At baseline, the median largest tumor diameter of these 30 patients was 9.2 cm (range: 3.5-15.0 cm), 26 patients had Barcelona Clinic Liver Cancer stage B-C, and 4 had stage A. Prior to surgery, all cases displayed tumor regression and 15 patients achieved objective response. Pathological complete response (pCR) was observed in 10 patients. No severe drug-related adverse events or surgical complications were observed. After a median follow-up of 16.5 months, 28 patients survived and 11 developed tumor recurrence. Survival analysis showed patients achieving tumor response before surgery or pCR had a longer tumor-free survival. Notably, patients with microvascular invasion (MVI) had significantly higher recurrence rate and poorer overall survival than patients without.

Conclusions

Lenvatinib combined with anti-PD-1 therapy represents a feasible conversion strategy for patients with initially unresectable HCC. Patients achieving tumor responses are more likely to benefit from conversion resection to access a longer term of tumor-free survival.

At the Intersection of Cardiology and Oncology: TGFβ as a Clinically Translatable Therapy for TNBC Treatment and as a Major Regulator of Post-Chemotherapy Cardiomyopathy

Simple Summary

Specific/targeted therapies have been shown to be effective in the treatment of certain cancers. Unfortunately, there is currently no targeted therapy for the treatment of triple-negative breast cancer (TNBC), which is why this subtype of breast cancer is associated with poor patient prognosis. While there is an immense focus on the development of new therapies, the issue of cardiotoxicity following chemotherapeutic treatment is commonly overlooked, despite its role as a leading cause of mortality in cancer survivors. This review aims to discuss the connection of TGF-β signaling and its role in modulating cardiac fibrosis and remodeling, as well as its role in TNBC tumor progression, cancer stem cell enrichment, chemoresistance and relapse. Together, we highlight the modulation of TGF-β as a method to target two of the greatest causes of morbidity and mortality in breast cancer patients.

Abstract

Triple-negative breast cancer (TNBC) is a subtype of breast cancer that accounts for the majority of breast cancer-related deaths due to the lack of specific targets for effective treatments. While there is immense focus on the development of novel therapies for TNBC treatment, a persistent and critical issue is the rate of heart failure and cardiomyopathy, which is a leading cause of mortality and morbidity amongst cancer survivors. In this review, we highlight mechanisms of post-chemotherapeutic cardiotoxicity exposure, evaluate how this is assessed clinically and highlight the transforming growth factor-beta family (TGF-β) pathway and its significance as a mediator of cardiomyopathy. We also highlight recent findings demonstrating TGF-β inhibition as a potent method to prevent cardiac remodeling, fibrosis and cardiomyopathy. We describe how dysregulation of the TGF-β pathway is associated with negative patient outcomes across 32 types of cancer, including TNBC. We then highlight how TGF-β modulation may be a potent method to target mesenchymal (CD44⁺/CD24⁻) and epithelial (ALDH^high) cancer stem cell (CSC) populations in TNBC models. CSCs are associated with tumorigenesis, metastasis, relapse, resistance and diminished patient prognosis; however, due to plasticity and differential regulation, these populations remain difficult to target and continue to present a major barrier to successful therapy. TGF-β inhibition represents an intersection of two fields: cardiology and oncology. Through the inhibition of cardiomyopathy, cardiac damage and heart failure may be prevented, and through CSC targeting, patient prognoses may be improved. Together, both approaches, if successfully implemented, would target the two greatest causes of cancer-related morbidity in patients and potentially lead to a breakthrough therapy.

Resolution of a hepatoduodenal fistula after nivolumab treatment in a patient with hepatocellular carcinoma: challenges in immunotherapy

Hepatocellular carcinoma is the fourth leading cause of cancer-related death worldwide, with limited treatment options for patients with advanced hepatocellular carcinoma. Beyond standard systemic therapy with multikinase inhibitors, recent studies demonstrate the potential for a robust and durable response with immune checkpoint inhibition in subsets of patients with hepatocellular carcinoma.We present a case of an 83-year-old male patient with the diagnosis of a multifocal hepatocellular carcinoma. A hepatoduodenal fistula developed under treatment with sorafenib which necessitated treatment interruption. Therefore, a switch to second line therapy with immunotherapy nivolumab was made and supportive enteral nutrition was started. This led to a spectacular oncological response, with complete resolution of the hepatoduodenal fistula. To our knowledge this is the first case which describes the involution of a fistula in a hepatocellular carcinoma under treatment with nivolumab.

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.

Insights into an Immunotherapeutic Approach to Combat Multidrug Resistance in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) has emerged as one of the most lethal cancers worldwide because of its high refractoriness and multi-drug resistance to existing chemotherapies, which leads to poor patient survival. Novel pharmacological strategies to tackle HCC are based on oral multi-kinase inhibitors like sorafenib; however, the clinical use of the drug is restricted due to the limited survival rate and significant side effects, suggesting the existence of a primary or/and acquired drug-resistance mechanism. Because of this hurdle, HCC patients are forced through incomplete therapy. Although multiple approaches have been employed in parallel to overcome multidrug resistance (MDR), the results are varying with insignificant outcomes. In the past decade, cancer immunotherapy has emerged as a breakthrough approach and has played a critical role in HCC treatment. The liver is the main immune organ of the lymphatic system. Researchers utilize immunotherapy because immune evasion is considered a major reason for rapid HCC progression. Moreover, the immune response can be augmented and sustained, thus preventing cancer relapse over the post-treatment period. In this review, we provide detailed insights into the immunotherapeutic approaches to combat MDR by focusing on HCC, together with challenges in clinical translation.

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.

Clinical outcomes and influencing factors of PD-1/PD-L1 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has an increasing incidence worldwide, and the global 5-year survival rate ranges from 5-30%. In China, HCC seriously threatens the nation's health; the incidence of HCC ranks fourth among all theriomas, and the mortality rate is the third highest worldwide. The main therapies for HCC are surgical treatment or liver transplantation; however, most patients with HCC will experience postoperative recurrence or metastasis, eventually resulting in mortality. As for advanced or unresectable HCC, the current appropriate treatment strategy is transarterial chemoembolization; however, limited therapeutic effect and natural or acquired drug resistance affect the efficacy of this approach. Previous studies have demonstrated that PD-L1 expression on host cells and myeloid cells plays an important role in PD-L1 blocked-mediated tumor regression. Thus, further research on programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1) is required. Countries including the United States, France, Britain and China have developed PD-1/PD-L1 blockers, including nivolumab, pembrolizumab, cemiplimab, atezolizumab, avelumab, durvalumab, toripalimab, sintilimab and camrelizumab. Notably, all of these blockers have therapeutic effect and influencing factors in HCC. Factors that influence the clinical outcome of PD-1 have also been discovered, such as inflammatory genes, specific receptors and signaling pathways. The discovery of these factors will help to identify novel methods, such as combination treatment, to decrease the influence of other factors on the efficacy of PD-1/PD-L1. Sorafenib and lenvatinib have been approved for first-line treatment for patients with advanced HCC. When first-line treatment frequently fails, pembrolizumab and ipilimumab plus nivolumab are used following sorafenib (but not lenvatinib) treatment in advanced HCC. Thus, tumor immunotherapy using PD-1/PD-L1 blockers exhibits promising outcomes for the treatment of HCC, and more novel PD-1/PD-L1 inhibitors are being developed to fight against this disease. The present review discusses the clinical results and influencing factors of PD-1/PD-L1 inhibitors in HCC to provide insight into the development and optimization of PD-1/PD-L1 inhibitors in the treatment of HCC.

Association of the Pretreatment Lung Immune Prognostic Index with Survival Outcomes in Advanced Hepatocellular Carcinoma Patients Treated with PD-1 Inhibitors

Purpose

At present, there are no validated biomarkers that can predict whether patients with advanced hepatocellular carcinoma (aHCC) are likely to benefit from anti-PD-1 therapy. We aimed to determine whether lung immune prognostic index (LIPI) is associated with outcomes in patients with aHCC treated with PD-1 inhibitors.

Patients and Methods

Patients undergoing initial treatment with PD-1 inhibitors for aHCC at a single center from January 1, 2015 to August 31, 2019 were included. The patients were stratified according to pretreatment LIPI based on a derived neutrophils/(leukocytes minus neutrophils) ratio (dNLR) ≥ 3 and a lactate dehydrogenase (LDH) level ≥ the upper limit of normal (ULN). Kaplan–Meier analysis and the Log rank test were used to calculate and compare survival between good LIPI and intermediate/poor LIPI scores. The prognostic values of LIPI for survival and disease control rate were evaluated using Cox proportional hazard and logistic regression models, respectively.

Results

Of the 108 study patients, 53 (49%) had a good LIPI (dNLR < 3 and LDH normal) and 55 (51%) had intermediate/poor LIPI (dNLR ≥ 3 or/and LDH ≥ ULN). With a median follow-up of 12.4 months, intermediate/poor LIPI was independently associated with shorter overall survival (OS) (hazard ratio [HR] 4.00; 95% CI, 2.00–8.03) and progression-free survival (PFS) (HR 2.65; 95% CI, 1.61–4.37). The median OS for good and intermediate/poor LIPI was not reached and was 13.7 (95% CI, 8.2–19.1) months, respectively, and the median PFS was 10.9 (95% CI, 8.9–12.9) and 4.0 (95% CI, 2.2–5.8) months (both P < 0.001), respectively.

Conclusion

Pretreatment LIPI combined with a dNLR ≥ 3 and/or LDH ≥ ULN is associated with poor outcomes in patients with aHCC treated with PD-1 inhibitors. Further validation in large, prospective studies are warranted.

Treatment patterns and direct medical costs among patients with advanced hepatocellular carcinoma

AIMS

This study assessed the real-world United States (US) treatment patterns and the associated economic burden in patients diagnosed with advanced hepatocellular carcinoma (HCC).

METHODS

The MarketScan database was used to identify patients newly diagnosed with HCC who received systemic therapy between 2011 and 2018 and continuously enrolled for ≥6 months (baseline period) prior and ≥1 month following HCC diagnosis. Treatment patterns (systemic and locoregional therapy), healthcare resource utilization, and costs were reported during follow-up.

RESULTS

The final sample included 1580 patients (median age, 61; 78% male; median follow up, 8.7 months). The most common first line of therapy (LOT) was sorafenib (78%). The median time from HCC diagnosis to start of sorafenib was 43 days, and the median duration of sorafenib therapy was 60 days. Only 17% of patients received second LOT, and non-sorafenib treatment use increased to 66% (mostly chemotherapy combination). Transarterial chemoembolization was the most commonly observed locoregional therapy prior to the first LOT. The multivariable-adjusted average all-cause total cost among sorafenib treated patients was $17,642 (95% CI: $16,711-$18,558) per-patient per-month), of which $11,393 were HCC-specific.

CONCLUSIONS

In patients who received first-line therapy for HCC, the duration of therapy was short (potentially due to progression or tolerability). Most patients did not continue to second-line therapy. Despite the short duration of therapy, HCC patients still incur a high economic burden, and there is a need for more effective and tolerable treatments.

Predictive value of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio in advanced hepatocellular carcinoma patients treated with anti-PD-1 therapy

Background

Currently, there are no recognized or validated biomarkers to identify hepatocellular carcinoma patients (HCC) likely to benefit from anti–PD‐1 therapy. We evaluated the relationship between neutrophil‐lymphocyte ratio (NLR) and platelet‐lymphocyte ratio (PLR) and survival outcomes, pretreatment and after three doses (posttreatment) of nivolumab in HCC patients.

Methods

Medical records of HCC patients treated with nivolumab between June 2016 and July 2018 were reviewed. Kaplan‐Meier analysis and the log‐rank test were used to calculate and compare overall survival between NLR < 5 Vs ≥ 5 and among PLR tertiles.

Results

A total of 103 patients were identified. Median age was 66 (29‐89) years. Median treatment duration was 26 (2‐149) weeks. Sixty‐four (62%) patients had Child‐Pugh class A (CP‐A) liver function. Barcelona Clinic Liver Cancer stage was B in 20 (19%) and C in 83 (81%) patients. CP‐A patients who achieved a partial or complete response had significantly lower posttreatment NLR and PLR (P < .001 for both) compared to patients who had stable disease or progression of disease. No relationship was observed between response and pretreatment NLR and PLR. NLR < 5 was associated with improved OS compared to NLR ≥ 5 both pretreatment (23 Vs10 months, P = .004) and posttreatment (35 Vs 9 months, P < .0001). Survival also differed significantly among PLR tertiles both pre‐ (P = .05) and posttreatment (P = .013). In a multivariable model, posttreatment NLR (HR = 1.10, P < .001) and PLR (HR = 1.002, P < .001) were strongly associated with survival. In a composite model of posttreatment NLR and PLR, a combination of high NLR and PLR was associated with an eightfold increased risk of death (HR = 8.3, P < .001).

Conclusions

This study suggests a strong predictive role of these inflammatory cell ratios in the posttreatment setting in HCC patients treated with anti anti–PD‐1 therapy and should be evaluated in a larger cohort.

Scientific Rationale for Combined Immunotherapy with PD-1/PD-L1 Antibodies and VEGF Inhibitors in Advanced Hepatocellular Carcinoma

A successful phase III trial for the combination of atezolizumab and bevacizumab (the IMbrave150 trial) in advanced hepatocellular carcinoma has recently been reported. This is groundbreaking because nivolumab and pembrolizumab, both programmed cell death-1 (PD-1) antibodies, have failed to show efficacy as first- and second-line therapeutics, respectively, in phase III clinical trials. Immunotherapy with a combination of atezolizumab and bevacizumab resulted in better survival than treatment with sorafenib for the first time since sorafenib was approved in 2007. The high efficacy of the combination of PD-1/programmed death ligand 1 (PD-L1) and vascular endothelial growth factor (VEGF) antibodies is not only due to their additive effects on tumor growth, but also to their reprogramming of the immunosuppressive microenvironment into an immunostimulatory microenvironment. These results were confirmed in a phase Ib trial that showed significantly longer progression-free survival in the atezolizumab plus bevacizumab group than in patients that received atezolizumab alone. These results demonstrate that immunotherapy with a combination of PD-1/PD-L1 and VEGF inhibitors is effective and may result in a reprogramming of the tumor microenvironment. The results of an ongoing phase III trial of a PD-1 antibody in combination with the VEGF receptor tyrosine kinase inhibitor (TKI) are highly anticipated.

Heterogeneous responses in hepatocellular carcinoma: the achilles heel of immune checkpoint inhibitors

Treatment of patients with hepatocellular carcinoma (HCC) remains a serious challenge due to high heterogeneity and limited treatment options. In the past few decades, immune therapy, especially immune checkpoint therapy, has become an alternative option for the treatment of malignancies including HCC. Immune checkpoint inhibitors (ICIs) have raised attention because of their significant antitumor effect and low toxicity. However, such immunotherapy fails to be responsive in a major proportion of patients with HCC. Recent studies suggest that failures in antigen presentation, an impaired immune microenvironment, alterations in immune checkpoint molecules and immune-suppressive cells are responsible for the heterogeneous responses and resistance. Based on the specific characteristics above, we proposed a model stratifying patients with HCC into two subtypes that could predict response or resistance to ICI. Furthermore, supplementing ICIs with agents targeting the microenvironment could achieve an increased response rate, which is a step forward in precision treatment for HCC. In addition, emerging studies have revealed that liver transplantation, epigenetic drugs and other novel strategies also provide synergistic effects with ICIs in the treatment of HCC.

Current Status and Future Direction of Immunotherapy in Hepatocellular Carcinoma: What Do the Data Suggest?

Most patients with hepatocellular carcinoma (HCC) are diagnosed at an advanced stage of disease. Until recently, systemic treatment options that showed survival benefits in HCC have been limited to tyrosine kinase inhibitors, antibodies targeting oncogenic signaling pathways or VEGF receptors. The HCC tumor microenvironment is characterized by a dysfunction of the immune system through multiple mechanisms, including accumulation of various immunosuppressive factors, recruitment of regulatory T cells and myeloid-derived suppressor cells, and induction of T cell exhaustion accompanied with the interaction between immune checkpoint ligands and receptors. Immune checkpoint inhibitors (ICIs) have been interfered this interaction and have altered therapeutic landscape of multiple cancer types including HCC. In this review, we discuss the use of anti-PD-1, anti-PD-L1, and anti-CTLA-4 antibodies in the treatment of advanced HCC. However, ICIs as a single agent do not benefit a significant portion of patients. Therefore, various clinical trials are exploring possible synergistic effects of combinations of different ICIs (anti-PD-1/PD-L1 and anti-CTLA-4 antibodies) or ICIs and target agents. Combinations of ICIs with locoregional therapies may also improve therapeutic responses.

Emerging agents and regimens for hepatocellular carcinoma

Liver cancer, mostly hepatocellular carcinoma (HCC), is the second leading cause of cancer mortality globally. Most patients need at least one systemic therapy at different phases of their treatment for HCC. Sorafenib was the first agent shown to improve the survival of patients with advanced HCC. A decade after the approval of sorafenib, most agents failed to improve patient survival more than sorafenib. In recent years, treatment practices have changed, with lenvatinib as another first-line treatment choice and regorafenib, ramucirumab, and cabozantinib as second-line treatment options. Anti-PD-1 antibodies, including nivolumab, pembrolizumab, and camrelizumab, have demonstrated promising anti-tumor effects as monotherapy for advanced HCC in phase II clinical trials. The combination of an anti-PD-1 antibody and an anti-angiogenesis agent has shown more potent anti-tumor effects in early phase clinical trials and is now the hotspot in clinical studies. Furthermore, these agents are investigated in combination treatment with surgery or other loco-regional therapies in patients with early or intermediate-stage HCC.

Immune landscape of hepatocellular carcinoma microenvironment: Implications for prognosis and therapeutic applications

The development of immunotherapy for solid tumours has boosted interest in the contexture of tumour immune microenvironment (TIME). Several lines of evidence indicate that the interplay between tumour cells and TIME components is a key factor for the evolution of hepatocellular carcinoma (HCC) and for the likelihood of response to immunotherapeutics. The availability of high-resolution methods will be instrumental for a better definition of the complexity and diversity of TIME with the aim of predicting disease outcome, treatment response and possibly new therapeutic targets. Here, we review current knowledge about the immunological mechanisms involved in shaping the clinical course of HCC. Effector cells, regulatory cells and soluble mediators are discussed for their role defining TIME and as targets for immune modulation, together with possible immune signatures for optimization of immunotherapeutic strategies.