Program death-1 immune checkpoint and tumor microenvironment in malignant liver tumors

Advances in the treatment of hepatocellular carcinoma: An overview of the current and evolving therapeutic landscape for clinicians

Hepatocellular carcinoma (HCC) is the sixth most common malignancy and the third leading cause of cancer-related death worldwide. Contemporary advances in systemic and locoregional therapies have led to changes in peer-reviewed guidelines regarding systemic therapy as well as the possibility of downstaging disease that may enable some patients with advanced disease to ultimately undergo partial hepatectomy or transplantation with curative intent. This review focuses on all modalities of therapy for HCC, guided by modern-day practice-changing randomized data where available. The surgical management of HCC, including resection and transplantation, both of which have evolving criteria for what is considered biologically resectable and transplantable, as well as locoregional therapy (i.e., therapeutic embolization, ablation, radiation, and hepatic arterial infusion), are discussed. Historical and modern-day practice-changing trials evaluating immunotherapy with targeted therapies for advanced disease, as well as adjuvant systemic therapy, are also summarized. In addition, this article examines the critical dimension of toxicities and patient-oriented considerations to ensure a comprehensive and balanced discourse on treatment implications.

Management of intrahepatic cholangiocarcinoma: a review for clinicians

Intrahepatic cholangiocarcinoma (iCCA) is an aggressive liver malignancy that arises from second-order biliary epithelial cells. Its incidence is gradually increasing worldwide. Well-known risk factors have been described, although in many cases, they are not identifiable. Treatment options are continuously expanding, but the prognosis of iCCA remains dismal. R0 liver resection remains the only curative treatment, but only a limited number of patients can benefit from it. Frequently, major hepatectomies are needed to completely remove the tumour. This could contraindicate surgery or increase postoperative morbidity in patients with chronic liver disease and small remnant liver volume. In cases of anticipated inadequate future liver remnant, regenerative techniques may be used to expand resectability. The role and extent of lymphadenectomy in iCCA are still matters of debate. Improvements in iCCA diagnosis and better understanding of genetic profiles might lead to optimized surgical approaches and drug therapies. The role of neoadjuvant and adjuvant therapies is broadening, gaining more and more acceptance in clinical practice. Combining surgery with locoregional therapies and novel drugs, such as checkpoint-inhibitors and molecular-targeted molecules, might improve treatment options and survival rates. Liver transplantation, after very poor initial results, is now receiving attention for the treatment of patients with unresectable very early iCCA (i.e. <2 cm) in cirrhotic livers, showing survival outcomes comparable to those of hepatocellular carcinoma. Ongoing prospective protocols are testing the efficacy of liver transplantation for patients with unresectable, advanced tumours confined to the liver, with sustained response to neoadjuvant treatment. In such a continuously changing landscape, the aim of our work is to review the state-of-the-art in the surgical and medical treatment of iCCA.

Downstaging strategies for unresectable hepatocellular carcinoma

A significant number of patients with hepatocellular carcinoma (HCC) are usually diagnosed in advanced stages, that leads to inability to achieve cure. Palliative options are focusing on downstaging a locally advanced disease. It is well-supported in the literature that patients with HCC who undergo successful conversion therapy followed by curative-intent surgery may achieve a significant survival benefit compared to those who receive chemotherapy alone or those who are successfully downstaged with conversion therapy but not treated with surgery. Hepatic artery infusion chemotherapy can be a potential downstaging strategy, since recent studies have demonstrated excellent outcomes in patients with colorectal liver metastatic disease as well as primary liver malignancies.

Optimizing Adjuvant Therapy after Surgery for Colorectal Cancer Liver Metastases: A Systematic Review

The liver is the most common site of colorectal cancer metastatic spread. Although metastasectomy is the gold standard for fit patients with resectable colorectal cancer liver metastases (CRLMs), their management after surgical treatment remains controversial. The objective of this systematic review was to collate the currently available data of the agents used in the adjuvant setting in order to define the most optimal therapeutic strategy. A systematic review of the literature was conducted by searching PubMed/Medline and Cochrane library databases. We included studies that evaluated the efficacy, the tolerability and the safety profile of various chemotherapeutic agents that are used as adjuvant treatment after surgical resection of CRLMs. The outcomes of interest were regression-free survival (RFS), disease-free survival (DFS), overall survival (OS) and severe toxicities. From 543 initial articles, 29 publications with 7028 patients were finally included. In general, the results of the eligible studies indicated that adjuvant therapy after resection of CRLMs led to improved RFS/DFS rates, but this benefit did not contribute to a statistically significant prolongation of OS. Moreover, the choice of the therapeutic strategy, namely systematic or regional chemotherapy or the combination of both, did not seem to have a differential impact on patient outcomes. However, these results should be interpreted with caution since the majority of the chosen studies are of low or moderate quality. In this context, further high-quality clinical trials conducted on patient sub-populations with modern therapies are required in order to reduce in-study and between-study heterogeneity and determine which patients are expected to derive the maximum benefit from adjuvant therapy after surgery for CRLMs.

Current status and novel insights into the role of metastasectomy in the era of immunotherapy

INTRODUCTION

New perspectives on the role of metastasectomy have emerged along with the advances in cancer immunotherapy. Despite accumulating evidence that encourages the use of immunotherapy in the metastatic setting, current data regarding its combination with surgical resection of secondary lesions, as well as the best timeline and sequence of such a therapeutic approach is limited.

AREAS COVERED

We review the currently available literature on the role of metastasectomy in the era of novel immunotherapeutic agents and provide comprehensive evidence from ongoing trials about the available treatment strategies. In metastatic melanoma, immune checkpoint inhibitors (ICIs) play a key role both in the neoadjuvant and adjuvant setting to achieve long-term disease control. In metastatic renal cell carcinoma, investigation is ongoing regarding the emerging role of ICIs before metastasectomy. ICIs have improved outcomes in patients with metastatic colorectal and head and neck cancer.

EXPERT OPINION

In the neoadjuvant setting, the high response rates and the durability of responses to immunotherapy may enable the resectability of metastatic lesions. In the adjuvant setting post metastasectomy, immunotherapy constitutes a safe and efficacious approach to support immune tumor surveillance and delay or even prevent disease relapse. Patient participation in relevant clinical trials should be encouraged.

Individualized Approach in the Surgical Management of Hepatocellular Carcinoma: Results from a Greek Multicentre Study

Background: Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the third leading cause of death worldwide. The management of HCC is complex, with surgical treatment providing long-term survival in eligible patients. This study aims to present the experience of aggressive surgical management of HCC in Greece. Methods: This is a retrospective multicentre clinical study with 242 patients. Results: Most patients were male (79%) and had a median age of 71 yrs. According to the most recent BCLC criteria, 172 patients (71.1%) were classified as BCLC 0-A stage, 33 patients (13.6%) were classified as BCLC B, and 37 (15.3%) were classified as BCLC C. A total of 54% of the patients underwent major hepatectomy. Major postoperative morbidity was 15.6%, and the 90-day postoperative mortality rate was 4.5%. The median follow-up was 33.5 months. Three- and five-year overall survival was 65% and 48%, respectively. The median overall survival was 55 months. Significantly, five-year survival was 55% for BCLC A, and 34% and 21% for BCLC B and C, respectively. In univariate analysis, cirrhosis, type of resection (R status), and BCLC stage were associated with overall survival. Multivariate analysis indicated that R1 and R2 resections compared to R0, and BCLC C compared to BCLC 0-A, were independently associated with increased mortality. Conclusions: Aggressive surgical treatment of HCC offers satisfactory long-term survival prospects. A significant percentage (29%) of HCCs that underwent liver resection were of the intermediate and advanced BCLC stage. The management of patients with HCC should be discussed in multidisciplinary tumour board meetings on a case-by-case basis to be more effective.

Horizons on the Therapy of Biliary Tract Cancers: A State-of-the-art Review

Biliary tract cancers (BTCs) comprise a group of heterogeneous poor prognosis cancers with increasing incidence recent years. The combination chemotherapy with cisplatin and gemcitabine is the first-line therapy for advanced BTC. There remains no accepted standard treatment in the second-line setting. Nowadays, more and more novel treatment strategies have entered development, with some encouraging results being seen. Here, we review the current treatment status and clinical characteristics of BTC, the role of immunotherapy in BTC as well as the design of clinical trials for oncology drugs for BTC which aim to focus on the future profiles of clinical care and resolution of BTC.

Absence of association between pretransplant serum soluble programmed death protein-1 level and prognosis following living donor liver transplantation in patients with hepatocellular carcinoma

ABSTRACT

Programmed death protein 1 (PD-1) pathway is one of the most critical mechanisms in tumor biology of hepatocellular carcinoma (HCC). The study aimed to assess the prognostic influence of pretransplant serum soluble PD-1 (sPD-1) in patients undergoing liver transplantation for treatment of HCC.Data from 229 patients with HCC who underwent living donor liver transplantation between January 2010 and December 2015 were retrospectively evaluated. Stored serum samples were used to measure sPD-1 concentrations.Overall survival (OS) and disease-free survival (DFS) rates were 94.3% and 74.5% at 1 year; 78.2% and 59.2% at 3 years; and 75.4% and 55.5% at 5 years, respectively. Prognostic analysis using pretransplant serum sPD-1 with a cut-off of 93.6 μg/mL (median value of the study cohort) did not have significant prognostic influence on OS (P = .69) and DFS (P = .26). Prognostic analysis using sPD-1 with a cut-off of 300 μg/mL showed similar OS (P = .46) and marginally lower DFS (P = .070). Combination of Milan criteria and sPD-1 with a cutoff of 300 μg/mL showed similar outcomes of OS and DFS in patients within and beyond Milan criteria. Multivariate analysis revealed that only Milan criteria was an independent prognostic for OS and DFS, but pretransplant sPD1 with a cut-off of 300 μg/mL did not become a prognostic factor.The results of this study demonstrate that pretransplant serum sPD-1 did not show significant influences on post-transplant outcomes in patients with HCC. Further large-scale, multicenter studies are necessary to clarify the role of serum sPD-1 in liver transplantation recipients.

The Emerging Role of Immunotherapy in Intrahepatic Cholangiocarcinoma

Biliary tract cancer, and intrahepatic cholangiocarcinoma (iCC) in particular, represents a rather uncommon, highly aggressive malignancy with unfavorable prognosis. Therapeutic options remain scarce, with platinum-based chemotherapy is being considered as the gold standard for the management of advanced disease. Comprehensive molecular profiling of tumor tissue biopsies, utilizing multi-omics approaches, enabled the identification of iCC’s intratumor heterogeneity and paved the way for the introduction of novel targeted therapies under the scope of precision medicine. Yet, the unmet need for optimal care of patients with chemo-refractory disease or without targetable mutations still exists. Immunotherapy has provided a paradigm shift in cancer care over the past decade. Currently, immunotherapeutic strategies for the management of iCC are under intense research. Intrinsic factors of the tumor, including programmed death-ligand 1 (PD-L1) expression and mismatch repair (MMR) status, are simply the tip of the proverbial iceberg with regard to resistance to immunotherapy. Acknowledging the significance of the tumor microenvironment (TME) in both cancer growth and drug response, we broadly discuss about its diverse immune components. We further review the emerging role of immunotherapy in this rare disease, summarizing the results of completed and ongoing phase I–III clinical trials, expounding current challenges and future directions.

Protein liposomes-mediated targeted acetylcholinesterase gene delivery for effective liver cancer therapy

BACKGROUND

Effective methods to deliver therapeutic genes to solid tumors and improve their bioavailability are the main challenges of current medical research on gene therapy. The development of efficient non-viral gene vector with tumor-targeting has very important application value in the field of cancer therapy. Proteolipid integrated with tumor-targeting potential of functional protein and excellent gene delivery performance has shown potential for targeted gene therapy.

RESULTS

Herein, we prepared transferrin-modified liposomes (Tf-PL) for the targeted delivery of acetylcholinesterase (AChE) therapeutic gene to liver cancer. We found that the derived Tf-PL/AChE liposomes exhibited much higher transfection efficiency than the commercial product Lipo 2000 and shown premium targeting efficacy to liver cancer SMMC-7721 cells in vitro. In vivo, the Tf-PL/AChE could effectively target liver cancer, and significantly inhibit the growth of liver cancer xenografts grafted in nude mice by subcutaneous administration.

CONCLUSIONS

This study proposed a transferrin-modified proteolipid-mediated gene delivery strategy for targeted liver cancer treatment, which has a promising potential for precise personalized cancer therapy.

The Epidemiology, Staging and Outcomes of Sarcomatoid Hepatocellular Carcinoma: A SEER Population Analysis

BACKGROUND

Hepatocellular carcinoma (HCC) subtypes differ in terms of histopathology and prognosis. Sarcomatoid HCC is rare and literature concerning the survival of patients with sarcomatoid HCC is scarce.

MATERIALS AND METHODS

Data of patients with sarcomatoid HCC, diagnosed from 1989 to 2016, were extracted from the Surveillance, Epidemiology and End Results (SEER) database. We evaluated the baseline and tumor related data, overall survival (OS), disease-specific survival and the performance (Harrell's concordance index - OS c-index) of the eighth edition of the American Joint Committee on Cancer TNM staging system (AJCC8). In addition, univariate and multivariate forward stepwise cox regression analyses were performed to identify factors associated with increased risk of death.

RESULTS

The SEER cohort consisted of 71 patients, mostly males (n=49, 69.0%), of White race (n=51, 71.8%) and the most common stage at presentation was stage IVB (n=30, 42.3%). The overall predictive ability of AJCC8 was mediocre, with an OS c-index=0.577 (SE=0.048). Surgery (hazard ratio=0.25, p<0.001) was significantly associated with reduced risk of death. Advanced TNM stage was not associated with increased risk of death.

CONCLUSION

Sarcomatoid HCC, a rare subtype of HCC, is associated with poor outcomes in terms of overall and disease-specific survival across all disease stages. Surgery seems to be of utmost importance. The eighth edition of the AJCC8 for HCC underperforms in predicting the survival of patients with sarcomatoid subtype.

Using Hepatocellular Carcinoma Tumor Burden Score to Stratify Prognosis after Liver Transplantation

Liver transplantation (LT) remains a mainstay of treatment for hepatocellular carcinoma (HCC). Tumor factors such as size and number of tumors define eligibility for LT using the Milan criteria. The tumor burden score (TBS) incorporates both tumor number and size into a single continuous variable and has been used to differentiate prognosis among patients undergoing resection for HCC. The objective of the present study was to evaluate the ability of the TBS to predict overall and recurrence-free survival in patients undergoing LT for HCC. The Scientific Registry of Transplant Recipients (SRTR) was used to analyze all liver transplants for HCC, with initial tumor size data from 2004 to 2018. There were 12,486 patients in the study period. In the unadjusted analyses, patients with a high TBS had worse overall (p < 0.0001) and recurrence-free (p < 0.0001) survival. In the adjusted analyses, a high TBS was associated with a greater hazard ratio (HR) of death (HR = 1.21; 95%CI, [1.13-1.30]; p < 0.001) and recurrence (HR = 1.49; 95%CI [1.3-1.7]; p < 0.001). When we superimposed the TBS on the Milan criteria, we saw that a higher TBS was associated with a higher hazard of recurrence at values that were either all within (HR = 1.20; 95%CI, [1.04-1.37]; p = 0.011) or variably within (HR = 1.53; 95%CI, [1.16-2.01]; p = 0.002) the Milan criteria. In conclusion, the TBS is a promising tool in predicting outcomes in patients with HCC after LT.

Immune Checkpoint Inhibitor-Induced Polymyositis and Myasthenia Gravis with Fatal Outcome

We here report on a 74-year-old man diagnosed with a pT3cN0 BRAF-mutated and mismatch repair-deficient adenocarcinoma in the colon ascendens and 3 liver metastases. After hemicolectomy, the patient received treatment with the PD-1 inhibitor pembrolizumab. Three weeks later (on day 22), laboratory tests showed leukocytosis and an increase in transaminases; immune checkpoint inhibitor (ICI)-induced hepatitis was suspected and prednisolone therapy was initiated. On day 29, the patient was acutely hospitalized due to dyspnea, somnolence and walking difficulties. Dysarthria, hoarseness, muscle pain and weakness had developed and the dose of prednisolone was increased. Serum levels of lactate dehydrogenase, creatine kinase and myoglobin were increased and ICI-induced myositis was suspected. Antibodies against acetylcholine receptor and titin were present, indicating myasthenia gravis. Eventually, bulbar myopathy developed, including dysarthria and dysphagia, and the patient could no longer attain saturation without oxygen. The patient was transferred to the intensive care unit, intubated and given methylprednisolone, intravenous immunoglobulins and infliximab. The patient developed carbon dioxide retention and died on day 39. Microscopical examination of the intercostal musculature, diaphragm, cervical musculature and tongue showed inflammatory infiltration and fibrosis consistent with a pronounced myositis. In the liver, microscopical examination did not show metastases from colorectal cancer but instead a hepatocellular cancer. The cause of death was determined as respiratory insufficiency due to polymyositis. In conclusion, ICIs may induce myositis combined with neurological immune-related adverse events. In patients developing muscle weakness and pain under ICI therapy, myositis should be suspected.

Systemic Therapy of Extensive Stage Small Cell Lung Cancer in the Era of Immunotherapy

OPINION STATEMENT

In March 2019, the FDA approved the use of the anti-programmed death ligand 1 (PD-L1) antibody atezolizumab, as a first-line treatment option in combination with platinum-etoposide (PE) for patients with extensive stage small cell lung cancer (ED SCLC) based upon the results of the IMpower133 trial. More recently, the FDA approved the anti-PD-L1 antibody durvalumab in March 2020 , also in the frontline setting for SCLC based upon the results of the CASPIAN trial. Both these trials demonstrated a small, but significant overall survival (OS) benefit with the addition of a PD-L1 antibody to standard chemotherapy in the treatment of ED SCLC, thereby altering the treatment paradigm for this aggressive disease. Previously, the FDA had approved the anti-PD1 antibodies nivolumab and pembrolizumab as single-agent third-line treatment options based upon encouraging phase 1/2 data in patients with relapsed SCLC who had not received prior immunotherapy (IO). Despite these recent advances, the overall benefit of IO in SCLC remains somewhat disappointing in comparison with the results seen in non-small cell lung cancer (NSCLC). To date, no reliable biomarkers exist to predict responsiveness to IO in SCLC, and the utility of second- or third-line immunotherapy is questionable in patients who have received IO as part of first-line treatment. There has also been minimal success in identifying targetable mutations in SCLC. Novel approaches include combination approaches with IO, including PARP inhibitors and CDK inhibitors. Few ongoing trials, however, have enrolled patients who have received frontline immunotherapy given the only recent change in standard of care. Consequently, the results of current trials evaluating second- and third-line therapies need to be interpreted and translated into clinical practice with caution. The most significant challenge in SCLC remains the identification of molecular targets for which drugs can be developed that can improve survival over the current standard of care.

Checkpoint Inhibition Causing Complete Remission of Metastatic Combined Hepatocellular-Cholangiocarcinoma after Hepatic Resection

Combined hepatocellular-cholangiocarcinoma (CHC) is a rare type of primary liver cancer, speculated to arise from hepatic progenitor cells, and with a worse prognosis than hepatocellular carcinoma (HCC). Serum alpha-fetoprotein (AFP) levels may be one prognostic factor. It has been suggested that checkpoint inhibition might be useful in the treatment of HCC where there is an increased expression of PD-1 and PD-L1 in the microenvironment. Its effect on CHC is unknown. We report a case with a large CHC, which was radically resected, but the 53-year-old female patient subsequently developed pulmonary metastases. Histology demonstrated low-differentiated CHC without microsatellite instability. Treatment with sorafenib was started but was stopped due to angioedema. Under subsequent gemcitabine/cisplatin treatment, the metastatic disease progressed with rising AFP levels. A third-line treatment with pembrolizumab was then started, 2 mg/kg b.w. i.v. every third week for 6 months. This resulted in a radiologically complete remission of the pulmonary metastases and AFP levels were normalized (<10 μg/L) from a level of 1,790 μg/L before treatment. The patient developed immune-related adverse events (AEs) including diarrhea and hepatitis. These AEs were successfully treated with prednisolone and mycophenolate mofetil, and they were eventually resolved. There are no signs of cancer recurrence neither in the liver nor in the lungs at 33 months after the start of the checkpoint inhibition treatment, and the patient is doing well. Further study is urgently needed on the role of checkpoint inhibition therapy in liver cancer.

Immunotherapy utilization for hepatobiliary cancer in the United States: disparities among patients with different socioeconomic status

Background

Patients with advanced hepatobiliary cancer (HBC) have a dismal prognosis and limited treatment options. Immunotherapy has been considered as a promising treatment, especially for cancers not amenable to surgery.

Methods

Between 2004, and 2015, patients diagnosed with hepatocellular carcinoma (HCC), intra- and extrahepatic cholangiocarcinoma and gallbladder cancer (GBC) were identified in the National Cancer Database.

Results

Among 249,913 patients with HBC, only 585 (0.2%) patients received immunotherapy. Among patients who received immunotherapy, most patients were diagnosed between 2012 and 2015, had private insurance, as well as an income ≥$46,000 and were treated at an academic facility. The use of immunotherapy among HBC patients varied by diagnosis (HCC, 67.7%; bile duct cancer, 14%). On multivariable analysis, a more recent period of diagnosis (OR 1.80, 95% CI: 1.44-2.25), median income >$46,000 (OR 1.43, 95% CI: 1.11-1.87), and higher tumor stage (stage III, OR 2.22, 95% CI: 1.65-3.01; stage IV, OR 3.24, 95% CI: 2.41-4.34) were associated with greater odds of receiving immunotherapy.

Conclusions

Overall utilization of immunotherapy in the US among patients with HBC was very low, yet has increased over time. Certain socioeconomic factors were associated with an increased likely of receiving immunotherapy, suggesting disparities in access of patients with lower socioeconomic status.

Liver Tumor Microenvironment

The tumor microenvironment (TME) has recently been recognized as an important part of tumor development and growth. TME is a dynamic system orchestrated by immune, cancer and inflammatory cells, as well as the stromal tissue and surrounding extracellular matrix. While TME of primary hepatic tumors is usually characterized by a strong inflammatory background, the TME of liver metastases typically consists of otherwise healthy liver tissue. Chronic inflammation and hypoxia are key to the development and progression of primary liver cancer. The injury caused by chronic inflammation creates a condition of immune evasion that initiates a cascade of events that eventually leads to liver carcinogenesis.With liver metastases, primary tumors "prime" the target organs via secreting factors that induce expansion of myeloid cell populations and create a solid ground for successful cancer settlement. Once in the liver, metastatic cells begin a neovascularization process that is driven mainly by VEGF and FGF. Due to high mortality rates associated with liver cancer, as well as the limited effective treatment options for advanced disease, new therapies are urgently needed. Targeting a single molecule in a number of interactions between the tumor and the TME is highly unlikely to reduce tumor growth. Future trials should focus on combination therapies (i.e. targeted therapies combined with immunotherapy) to treat liver malignancies efficiently.

In tumor cells, thyroid hormone analogues non-immunologically regulate PD-L1 and PD-1 accumulation that is anti-apoptotic

The PD-1/PD-L1 immune checkpoint involving tumor cells and host immune defense lymphocytes is a well-studied therapeutic target in oncology. That PD-1 and PD-L1 may have additional functions within tumor cells that are independent of the checkpoint is indicated by actions of a thyroid hormone analogue, L-thyroxine (T₄), on these checkpoint components. Acting at a cell surface receptor on plasma membrane integrin αvβ3, T₄ stimulates intracellular accumulation of PD-L1 in cancer cells. In these thyroid hormone-treated cells, T₄-induced PD-L1 is non-immunologically anti-apoptotic, blocking activation of p53. Several laboratories have also described accumulation of PD-1 in a variety of cancer cells, not just immune defense lymphocytes and macrophages. Preliminary observations indicate that T₄ stimulates intracellular accumulation of PD-1 in tumor cells, suggesting that, like PD-L1, PD-1 has non-immunologic roles in the setting of cancer. Where such roles are anti-apoptotic, thyroid hormone-directed cancer cell accumulation of PD-1 and PD-L1 may limit effectiveness of immunologic therapy directed at the immune checkpoint.