Neoadjuvant sintilimab and chemotherapy in patients with potentially resectable esophageal squamous cell carcinoma (KEEP-G 03): an open-label, single-arm, phase 2 trial

BACKGROUND

The standard neoadjuvant treatments in patients with esophageal squamous cell carcinoma (ESCC) still have either poor safety or efficacy. Better therapies are needed in China.

METHODS

This was an open-label, single-arm, phase 2 trial. Patients with potentially resectable ESCC (cT1b-3, Nany, M0 or T4a, N0-1, or M0) received preoperative intravenous sintilimab plus triplet chemotherapy (liposomal paclitaxel, cisplatin, and S-1) every 3 weeks for two cycles. The primary endpoints were safety and surgical feasibility; the secondary endpoint was major pathological response (MPR) rate. Genomic biomarkers (genetic mutations, tumor mutational burden (TMB), circulating tumor DNA status and immune microenvironment) in baseline tumor samples were investigated.

RESULTS

All 30 patients completed two cycles of neoadjuvant treatment and underwent surgical resection. Grade 3-4 treatment-related adverse events (TRAEs) occurred in 36.7% (11/30) of patients. The most frequent TRAEs were decreased white cell count (76.7%), anemia (76.7%), and decreased neutrophil count (73.3%). All TRAEs were hematological toxicities; none caused ≥30 days surgical delay. The MPR and pathological complete response (pCR) rates were 50.0% (15/30; 95% CI 33.2 to 66.9) and 20.0% (6/30; 95% CI 9.5 to 37.3), respectively. Patients with higher TMB and more clonal mutations were more likely to respond. ERBB2 alterations and ctDNA high-releaser status have a negative correlation with neoadjuvant ICI response. No significant difference was observed between therapeutic response and tumor immune microenvironment.

CONCLUSIONS

Neoadjuvant sintilimab plus platinum-based triplet chemotherapy appeared safe and feasible, did not delay surgery and induced a pCR rate of 20.0% in patients with potentially resectable ESCC.

TRIAL REGISTRATION NUMBER

NCT03946969.

Overcoming the cardiac toxicities of cancer therapy immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) have led recent advances in the field of cancer immunotherapy improving overall survival in multiple malignancies with abysmal prognoses prior to their introduction. The remarkable efficacy of ICIs is however limited by their potential for systemic and organ specific immune-related adverse events (irAEs), most of which present with mild to moderate symptoms that can resolve spontaneously, with discontinuation of therapy or glucocorticoid therapy. Cardiac irAEs however are potentially fatal. The understanding of autoimmune cardiotoxicity remains limited due to its rareness. In this paper, we provide an updated review of the literature on the pathologic mechanisms, diagnosis, and management of autoimmune cardiotoxicity resulting from ICIs and their combinations and provide perspective on potential strategies and ongoing research developments to prevent and mitigate their occurrence.

Cardiovascular toxicity following immune checkpoint inhibitors: A systematic review and meta-analysis

BACKGROUND

Immune checkpoint inhibitors may be associated with multiple immune-related toxicities. Cardiovascular adverse effects are underreported in clinical trials.

METHODS

We conducted a systematic review and meta-analysis to evaluate cardiovascular adverse effects incidence among patients with solid tumors receiving immune checkpoint inhibitors in randomized clinical trials and the relative risk of presenting these effects compared to placebo or best supportive care. The search was conducted through MEDLINE, Embase, and Scopus databases from January 1st, 2010 until July 1st, 2020. Outcomes were reported following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines.

RESULTS

57 randomized clinical trials including 12,118 patients were included. All grade CV AEs incidence rate was 8.32% (95% CI = 6.35%-10.53%). When only grade 3-5 CV AEs were considered, ICIs were significantly associated with increased risk than placebo or BSC (RR = 1.36; 95% CI = 1.06-1.73; p = 0.01).

CONCLUSION

This meta-analysis corroborates the hypothesis of increased CV risk related to immune checkpoint inhibitors.

Predictive biomarkers of response to immune checkpoint inhibitors in hepatocellular carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and fourth leading cause of cancer death. While drug discovery to improve disease survival was historically poor, there is now evidence of significant potential for immune checkpoint inhibitors (ICPIs) in treatment of the disease, and indeed such drug approvals are beginning to emerge.

AREAS COVERED

HCC typically arises in the context of cirrhosis and chronic liver disease (CLD), and HCC exhibits significant biological heterogeneity, in part reflecting the broad range of aetiologies of CLD. Different classes and combinations of ICPI-based therapy exist, but not all patients will respond and predictive biomarkers are not yet available to guide clinician decision making, unlike some other cancer types. In this review, we discuss the emerging biomarkers for ICPI sensitivity in HCC, including tumour genomic features, perturbation of the gut microbiome and systemic inflammatory markers.

EXPERT OPINION

Additional profiling studies are required to appreciate existing trends with clinical outcome and to further drive clinical studies in disease stratification by response. This will only be possible within collaborative and international efforts, especially regarding biopsy collection. A close collaboration between basic scientists and clinicians will be the key to shape the next future of HCC biomarker research.

Predictive biomarkers for response to immune checkpoint inhibition

Immune checkpoint inhibitors have transformed the prognosis and treatment paradigm of many cancer types, through the potential for durable responses. However, the majority of patients still do not benefit. Response to checkpoint inhibition is determined by dynamic host, tumour and tumour microenvironment factors that display spatial and temporal variability, but our understanding of these interactions is incomplete. Through investigating biomarkers of resistance and response, opportunities arise to discover new therapeutic targets and shape personalised treatment strategies. Here we review approved and emerging biomarkers of response to immune checkpoint inhibitors, in particular the recent rapid progress in host and tumour genomics. It is unlikely that a single biomarker will precisely predict response, but multivariate multiomic markers may provide a balanced assessment of these factors and more accurately identify patients who will benefit. Further efforts are required to translate these groundbreaking discoveries into novel therapeutics and biomarker driven clinical trials, to provide durable treatment response to a greater population of patients.

Alterations in DNA damage response and repair genes as potential biomarkers for immune checkpoint blockade in gastrointestinal cancer

Objective:

Immune checkpoint inhibitors (ICIs) have achieved remarkable results in cancer treatments. However, there is no effective predictive biomarker for gastrointestinal (GI) cancer.

Methods:

We conducted integrative analyses of the genomic and survival data of ICI-treated GI cancer patients from the Memorial Sloan Kettering Cancer Center cohort (MSK-GI, n = 227), the Janjigian cohort (n = 40), and the Peking University Cancer Hospital & Institute cohort (PUCH, n = 80) to determine the possible associations between DNA damage response and repair (DDR) gene mutations and clinical outcomes. Data from The Cancer Genome Atlas database were analyzed to determine the possible correlations between DDR gene mutations and the tumor microenvironment.

Results:

In the MSK cohort, the presence of ≥ 2 DDR gene mutations was correlated with prolonged overall survival (OS). The Janjigian and PUCH cohorts further confirmed that subgroups with ≥ 2 DDR gene mutations displayed a prolonged OS and a higher durable clinical benefit. Furthermore, the DDR gene mutation load could be considered as an independent prognostic factor, and exhibited a potential predictive value for survival in GI cancer patients treated with ICIs. Mechanistically, we showed that the presence of ≥ 2 DDR gene mutations was correlated with higher levels of tumor mutation burden, neoantigen, and T cell infiltration.

Conclusions:

The DDR gene mutation status was correlated with favorable clinical outcomes in GI cancer patients receiving ICIs, which could serve as a potential biomarker to guide patient selection for immunotherapy.

Metabolic and Immunological Subtypes of Esophageal Cancer Reveal Potential Therapeutic Opportunities

BACKGROUND

Esophageal cancer has the sixth highest rate of cancer-associated deaths worldwide, with many patients displaying metastases and chemotherapy resistance. We sought to find subtypes to see if precision medicine could play a role in finding new potential targets and predicting responses to therapy. Since metabolism not only drives cancers but also serves as a readout, metabolism was examined as a key reporter for differences.

METHODS

Unsupervised and supervised classification methods, including hierarchical clustering, partial least squares discriminant analysis, k-nearest neighbors, and machine learning techniques, were used to discover and display two major subgroups. Genes, pathways, gene ontologies, survival, and immune differences between the groups were further examined, along with biomarkers between the groups and against normal tissue.

RESULTS

Esophageal cancer had two major unique metabolic profiles observed between the histological subtypes esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC). The metabolic differences suggest that ESCC depends on glycolysis, whereas EAC relies more on oxidative metabolism, catabolism of glycolipids, the tricarboxylic acid (TCA) cycle, and the electron transport chain. We also noted a robust prognostic risk associated with COQ3 expression. In addition to the metabolic alterations, we noted significant alterations in key pathways regulating immunity, including alterations in cytokines and predicted immune infiltration. ESCC appears to have increased signature associated with dendritic cells, Th17, and CD8 T cells, the latter of which correlate with survival in ESCC. We bioinformatically observed that ESCC may be more responsive to checkpoint inhibitor therapy than EAC and postulate targets to enhance therapy further. Lastly, we highlight correlations between differentially expressed enzymes and the potential immune status.

CONCLUSION

Overall, these results highlight the extreme differences observed between the histological subtypes and may lead to novel biomarkers, therapeutic strategies, and differences in therapeutic response for targeting each esophageal cancer subtype.

Is advanced esophageal adenocarcinoma a distinct entity from intestinal subtype gastric cancer? Data from the AGAMENON-SEOM Registry

BACKGROUND

Advanced esophageal adenocarcinoma (EAC) is generally treated similarly to advanced gastroesophageal junction (GEJ-AC) and gastric (GAC) adenocarcinomas, although GAC clinical trials rarely include EAC. This work sought to compare clinical characteristics and treatment outcomes of advanced EAC with those of GEJ-AC and GAC and examine prognostic factors.

PATIENTS AND METHODS

Participants comprised patients with advanced EAC, intestinal GEJ-AC, and GAC treated with platin and fluoropyrimidine (plus trastuzumab when HER2 status was positive). Overall and progression-free survival were estimated using the Kaplan-Meier method. Cox proportional hazards regression gauged the prognostic value of the AGAMENON model.

RESULTS

Between 2008 and 2019, 971 participants from the AGAMENON-SEOM registry were recruited at 35 centers. The sample included 67.3% GAC, 13.3% GEJ-AC, and 19.4% EAC. Pulmonary metastases were most common in EAC and peritoneal metastases in GAC. Median PFS and OS were 7.7 (95% CI 7.3-8.0) and 13.9 months (12.9-14.7). There was no difference in PFS or OS between HER2- and HER2+ tumors from the three locations (p > 0.05). Five covariates were found to be prognostic for the entire sample: ECOG-PS, histological grade, number of metastatic sites, NLR, and HER2+ tumors treated with trastuzumab. In EAC, the same variables were prognostic except for grade. The favorable prognosis for HER2+ cancers treated with trastuzumab was homogenous for all three subgroups (p = 0.351) and, after adjusting for the remaining covariates, no evidence supported primary tumor localization as a prognostic factor (p = 0.331).

CONCLUSION

Our study supports the hypothesis that EAC exhibits clinicopathological characteristics, prognostic factors, and treatment outcomes comparable to intestinal GEJ-AC and GAC.

Tislelizumab in Chinese patients with advanced solid tumors: an open-label, non-comparative, phase 1/2 study

BACKGROUND

Tislelizumab is an investigational, humanized, IgG4 monoclonal antibody with high affinity and binding specificity for programmed cell death-1 (PD-1) that was engineered to minimize binding to FcγR on macrophages in order to abrogate antibody-dependent phagocytosis, a mechanism of T-cell clearance and potential resistance to anti-PD-1 therapy.

METHODS

The purpose of this phase 1/2, open-label, non-comparative study was to examine the safety, tolerability, and antitumor activity of tislelizumab in adult (≥18 years) Chinese patients with histologically or cytologically confirmed advanced solid tumors with measurable disease. The phase 1 portion of the study consisted of a dose-verification study and a pharmacokinetic (PK) substudy; phase 2 was an indication-expansion study including 11 solid tumor cohorts. Patients previously treated with therapies targeting PD-1 or its ligand, programmed cell death ligand-1 were excluded. During dose-verification, dose-limiting toxicities (DLTs) were monitored; safety and tolerability were examined and the previously determined recommended phase 2 dose (RP2D) was verified. The primary endpoint of phase 2 was investigator-assessed objective response rate per Response Evaluation Criteria in Solid Tumors V.1.1.

RESULTS

As of December 1, 2018, 300 patients were treated with tislelizumab 200 mg intravenously once every 3 weeks (Q3W). Median duration of follow-up was 8.1 months (range 0.2-21.9). No DLTs were reported during the phase 1 dose-verification study and the RP2D was confirmed to be 200 mg intravenously Q3W. Most treatment-related adverse events (62%) were grade 1 or 2, with the most common being anemia (n=70; 23%) and increased aspartate aminotransferase (n=67; 22%). Of the 251 efficacy evaluable patients, 45 (18%) achieved a confirmed clinical response, including one patient from the PK substudy who achieved a complete response. Median duration of response was not reached for all except the nasopharyngeal carcinoma cohort (8.3 months). Antitumor responses were observed in multiple tumor types.

CONCLUSIONS

Tislelizumab was generally well tolerated among Chinese patients. Antitumor activity was observed in patients with multiple solid tumors.

TRIAL REGISTRATION NUMBER

CTR20160872.

Oxidative Stress and the Intersection of Oncogenic Signaling and Metabolism in Squamous Cell Carcinomas

Squamous cell carcinomas (SCCs) arise from both stratified squamous and non-squamous epithelium of diverse anatomical sites and collectively represent one of the most frequent solid tumors, accounting for more than one million cancer deaths annually. Despite this prevalence, SCC patients have not fully benefited from recent advances in molecularly targeted therapy or immunotherapy. Rather, decades old platinum-based or radiation regimens retaining limited specificity to the unique characteristics of SCC remain first-line treatment options. Historically, a lack of a consolidated perspective on genetic aberrations driving oncogenic transformation and other such factors essential for SCC pathogenesis and intrinsic confounding cellular heterogeneity in SCC have contributed to a critical dearth in effective and specific therapies. However, emerging evidence characterizing the distinct genomic, epigenetic, and metabolic landscapes of SCC may be elucidating unifying features in a seemingly heterogeneous disease. In this review, by describing distinct metabolic alterations and genetic drivers of SCC revealed by recent studies, we aim to establish a conceptual framework for a previously unappreciated network of oncogenic signaling, redox perturbation, and metabolic reprogramming that may reveal targetable vulnerabilities at their intersection.

PD-L1 as a biomarker of response to immune-checkpoint inhibitors

Immune-checkpoint inhibitors targeting PD-1 or PD-L1 have already substantially improved the outcomes of patients with many types of cancer, although only 20-40% of patients derive benefit from these new therapies. PD-L1, quantified using immunohistochemistry assays, is currently the most widely validated, used and accepted biomarker to guide the selection of patients to receive anti-PD-1 or anti-PD-L1 antibodies. However, many challenges remain in the clinical use of these assays, including the necessity of using different companion diagnostic assays for specific agents, high levels of inter-assay variability in terms of both performance and cut-off points, and a lack of prospective comparisons of how PD-L1⁺ disease diagnosed using each assay relates to clinical outcomes. In this Review, we describe the current role of PD-L1 immunohistochemistry assays used to inform the selection of patients to receive anti-PD-1 or anti-PD-L1 antibodies, we discuss the various technical and clinical challenges associated with these assays, including regulatory issues, and we provide some perspective on how to optimize PD-L1 as a selection biomarker for the future treatment of patients with solid tumours.

Cytokine-chemokine network driven metastasis in esophageal cancer; promising avenue for targeted therapy

Esophageal cancer (EC) is a disease often marked by aggressive growth and poor prognosis. Lack of targeted therapies, resistance to chemoradiation therapy, and distant metastases among patients with advanced disease account for the high mortality rate. The tumor microenvironment (TME) contains several cell types, including fibroblasts, immune cells, adipocytes, stromal proteins, and growth factors, which play a significant role in supporting the growth and aggressive behavior of cancer cells. The complex and dynamic interactions of the secreted cytokines, chemokines, growth factors, and their receptors mediate chronic inflammation and immunosuppressive TME favoring tumor progression, metastasis, and decreased response to therapy. The molecular changes in the TME are used as biological markers for diagnosis, prognosis, and response to treatment in patients. This review highlighted the novel insights into the understanding and functional impact of deregulated cytokines and chemokines in imparting aggressive EC, stressing the nature and therapeutic consequences of the cytokine-chemokine network. We also discuss cytokine-chemokine oncogenic potential by contributing to the Epithelial-Mesenchymal Transition (EMT), angiogenesis, immunosuppression, metastatic niche, and therapeutic resistance development. In addition, it discusses the wide range of changes and intracellular signaling pathways that occur in the TME. Overall, this is a relatively unexplored field that could provide crucial insights into tumor immunology and encourage the effective application of modulatory cytokine-chemokine therapy to EC.

A systematic review and meta-analysis of PD-1/PD-L1 inhibitors in specific patient subgroups with advanced gastro-oesophageal junction and gastric adenocarcinoma

BACKGROUND

immune checkpoint inhibitors(ICIs) have shown contradictory results in patients with advanced gastro-oesophageal junction/gastric cancer(GOJ/GC).

AIM

to identify specific patient subgroups that would derive survival benefit from ICIs.

METHODS

a subgroup meta-analysis of randomised clinical trials(RCTs) was carried out.

RESULTS

four phase-III-RCTs were identified with data on the following variables: primary location(Gastric vs GOJ); age(≤ 65 vs >65); gender(male vs female); ECOG PS(0 vs 1); ethnicity (Asian vs non-Asian), histology(intestinal vs diffuse), PD-L1 expression(≥ 1% vs < 1%). PD-L1 positivity was significantly associated with survival benefit from ICIs (HR: 0.82, p 0.047), with a significant interaction between PD-L1 expression and ICI efficacy (interaction HR: 1.41, p 0.02). Numerically, the second most relevant interaction was ICI efficacy and gender, with ICI being more effective in males.

CONCLUSION

The PD-L1 positive patient subgroup derives significant survival benefit from ICI in GOJ/GC, however other predictors are eagerly needed to further refine patient selection.

Immunotherapy in gastroesophageal cancers: Current state and future directions

While gastroesophageal (GE) cancers are one of the most common cancers worldwide, unfortunately, the mortality remains high. Commonly used treatment options include surgical resection, chemotherapy, radiotherapy, and molecular targeted therapy, which improve survival only minimally; thus, affirming the dire need for exploring alternative strategies to improve patient outcomes. Immunotherapy, which has revolutionized the world of oncology, has somewhat lagged behind in GE malignancies. Tumor-associated microenvironment and regulatory T cells, alongside cell cycle checkpoints, have been proposed by various studies as the mediators of carcinogenesis in GE cancers. Thus, inhibition of each of these could serve as a possible target of treatment. While the approval of pembrolizumab has provided some hope, it is not enough to override the dismal prognosis that this disease confers. Herein, we discuss the prospects of immunotherapy in this variety of cancer.

Advances in the pharmacotherapeutic management of esophageal squamous cell carcinoma

INTRODUCTION

Esophageal squamous cancer remains an important cause of mortality worldwide with two new immunotherapy drugs recently approved for metastatic disease.

AREAS COVERED

The authors review the epidemiology and genomics of esophageal squamous cell carcinoma. They also examine prior trials involving targeted agents under investigation as well immunotherapies that have been approved and novel combinations.

EXPERT OPINION

Great advances have been made in characterizing the molecular changes in esophageal carcinoma. However, relatively few drugs have shown benefit in this disease. Targeted therapies have not shown to improve survival although many of these trials did not explore potential biomarkers. Pembrolizumab and nivolumab are now approved for esophageal squamous carcinoma but much more data are needed to understand how these agents may be used in non-metastatic settings. Novel treatments are still required as overall prognosis remains poor.

Recent advances in treating oesophageal cancer

Esophageal cancer (EC) is an aggressive malignancy with an increasing incidence and a poor prognosis. EC is histologically divided into two major categories: adenocarcinoma (EAC) and squamous cell carcinoma (ESCC). EAC and ESCC are molecularly different and therefore treatments should reflect the respective histological subtype. Combined modality therapy is needed for localized EC. When EC is advanced (stage 4), systemic therapy is the mainstay treatment for palliation. For localized EC, several strategies are considered standard, and more trials are necessary to determine a unified and more effective approach. The management for advanced EC is slowly evolving as immunotherapy is showing some promise for ESCC, but more data from ongoing studies are anticipated. Treatment advances will be based on high-definition genomic investigation of individual tumors. Herein, we review the contemporary trends in diagnosing and treating EAC and ESCC.

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

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

Role of Immunotherapy in Advanced Gastroesophageal Cancer

PURPOSE OF REVIEW

Immunotherapy and tumor microenvironment have been at the forefront of cancer research over the past several decades. Here, we will review the role of immunotherapy in advanced gastroesophageal cancers including targeted antibodies, immunomodulating agents, vaccines, oncolytic virus therapy, and adoptive immunotherapy, and discuss the future direction for immunotherapy in this population.

RECENT FINDINGS

Targeted antibodies are already standard-of-care. An anti-PD-1 monoclonal antibody is currently FDA approved for second-line treatment of locally advanced or metastatic ESCC, as well as beyond second-line treatment of advanced G/GEJ cancers, and recent data suggests it may be considered in first-line treatment of advanced G/GEJ cancers. Combination therapies such as immunotherapy plus chemotherapy and/or radiotherapy, vaccines, oncolytic viral therapy, and adoptive immunotherapy in varying combinations are currently under active investigation. Several trials are ongoing and are hoped to reach more efficacious and individualized treatment options in advanced gastroesophageal cancer, where novel treatment options are desperately needed.

Immunotherapy in Gastrointestinal Cancers

Background

Gastrointestinal malignancies have both a high incidence rate and a high mortality rate. Immuno-oncological treatment approaches are becoming increasingly established in the treatment of gastrointestinal cancers.

Summary

In this review, we give an overview of the types and effects of immunotherapies. We focus on recent studies on immunotherapies with special attention to immune checkpoint inhibition in carcinomas of the esophagus and stomach, the hepato-pancreatico-biliary system, and the colorectum including the anal channel in the metastatic setting, and we show their achievements but also their limitations. In an outlook, we discuss new approaches in immunotherapy like CAR T-cell therapy and oncolytic viruses.

Key Messages

Gastrointestinal cancers show overall moderate response rates to immunotherapy. Nevertheless, subgroups such as DNA mismatch repair-deficient or microsatellite-instable tumors particularly benefit from the immune checkpoint blockade. Further studies are ongoing.

Comparative risk of serious and fatal treatment-related adverse events caused by 19 immune checkpoint inhibitors used in cancer treatment: a network meta-analysis

BACKGROUND

This network meta-analysis assessed the comparative risk of grade 3-5 and grade 5 treatment-related adverse events (TRAEs) for immune checkpoint inhibitors (ICIs), either alone or in combination with other modalities, for cancer treatment.

METHODS

PubMed, Embase, Cochrane Library, Web of Science, and recent predominant oncology congresses were searched for relevant phase II and phase III randomized controlled trials (RCTs). As outcomes, grade 3-5, and grade 5 TRAE outcomes were reported as odds ratios and 95% confidence intervals.

RESULTS

In 67 RCTs involving 36,422 patients and 19 ICIs, the incidence of grade 3-5 and grade 5 TRAEs was 17.9% and 0.8% with ICI monotherapy and 46.3% and 1.4%, respectively, with combinatorial therapy. Pneumonitis was the most common cause of grade 5 TRAEs following either monotherapy (16.3%) or combinatorial therapy (11.4%). Regarding grade 3-5 TRAEs, atezolizumab + chemotherapy (CT) and antiangiogenic therapy (AT) (atezolizumab + CAT), pembrolizumab + CT, ipilimumab + CT, and atezolizumab + CT were more toxic than any ICI monotherapy, pembrolizumab or nivolumab + radiotherapy (RT), and ICIs dual therapy (durvalumab + tremelimumab and nivolumab + ipilimumab). Tremelimumab, ipilimumab, durvalumab, and pembrolizumab were, however, associated with higher grade 5 TRAEs than combinatorial treatments. Atezolizumab + CAT was the most toxic and nivolumab + RT was the least toxic of combinatorial treatments; among monotherapies, tremelimumab and avelumab were the most and least toxic, respectively. The toxicity ranking changed with type of grade 3-5 TRAEs.

CONCLUSIONS

Compared with combinatorial therapy, ICI monotherapy caused lower grade 3-5 TRAEs, but some monotherapies resulted in a higher incidence of fatal TRAEs. Atezolizumab + CAT and nivolumab + RT were the most and least toxic of combinatorial treatments, respectively, and tremelimumab and avelumab were the most and least toxic of the monotherapies, respectively.

Pembrolizumab for the treatment of esophageal cancer

INTRODUCTION

Esophageal cancer (EC) is the seventh most common cancer and the sixth leading cause of cancer death. However, the prognosis of unresectable advanced or recurrent EC patients remains poor and there are few effective therapeutic agents for EC. Pembrolizumab is a monoclonal antibody that exerts anti-tumor activity by inhibiting the interaction of programmed cell death protein 1 with its ligand (PD-L1) on activated lymphocytes. Pembrolizumab monotherapy shows a significant survival benefit in metastatic or recurrent EC patients with PD-L1 CPS ≥10 as second-line treatment.

AREA COVERED

In this review, we provide an overview of pembrolizumab as a compound and present the available clinical data related to EC treatment.

EXPERT OPINION

In our opinion, pembrolizumab is one of the standard treatment agents for second-line metastatic or recurrent esophageal squamous cell carcinoma patients with PD-L1 CPS ≥10. Trials assessing the efficacy of a combination of cytotoxic agents and pembrolizumab as first-line treatment and pembrolizumab-containing chemoradiation are ongoing. Their results may provide important data to improve clinical outcomes.

Immune checkpoint inhibitors: Key trials and an emerging role in breast cancer

This review focuses on immune checkpoint inhibitors - immunomodulatory agents that aim to relieve tumour-mediated immune-cell suppression. Immune checkpoint proteins can be expressed on the tumour-cell or immune-cell populations. Immune checkpoint proteins dampen the immune response by inactivating immune cells capable of tumour destruction. Blockade of immune checkpoints has shown impressive results in a range of solid cancers, particularly melanoma and non-small cell lung cancer. The potential benefit of this class of drugs is widespread across most cancer types and an unprecedented number of clinical studies are underway to examine the benefit of these agents. The aims of this review are to: provide an overview of the key early immune checkpoint inhibitor trials involving drugs targeting programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) in multiple disease types; provide an overview of emerging therapies aimed at these targets; and provide a detailed exploration of the status of immune checkpoint inhibitors in breast cancer.

Palliation of dysphagia in metastatic oesogastric cancers: An international multidisciplinary position

Malignant dysphagia is the most common symptom in advanced oesogastric cancers patients. Relief of dysphagia allows quality of life improvement, nutritional replenishment and potentially improves prognosis. Chemotherapy alone is effective and should be prioritised in patients with metastatic disease a good performance status, and its impact on dysphagia should be determined before further interventions are planned. Regarding local treatments, the insertion of a covered self-expandable metallic stent is the most commonly used alternative, as it allows for the rapid relief of severe dysphagia. Although several randomised trials have highlighted the role of oesophageal brachytherapy, this technique is often not easily accessible. Contemporary trials are ongoing to better define the role of external radiation therapy. While awaiting these results, external radiation therapy can be considered as a second-best option for patients with a life-expectancy > 3 months. It is important to offer nutritional support and to integrate quality of life measures in the palliative management of dysphagia. This multidisciplinary international position paper aims to propose a decision-making process and highlight randomised trials for the management of malignant dysphagia in metastatic oesogastric cancer patients.

Synergism Between Immunotherapy and Radiotherapy in Esophageal Cancer: An Overview of Current Knowledge and Future Perspectives

Background: Esophageal cancer (EC) is an aggressive neoplasm of the gastrointestinal tract that is usually treated with a combination of chemotherapy, radiotherapy (RT), and/or surgery, according to disease status. Despite the availability of multimodal therapeutic strategies, local recurrence is frequently observed. Immunotherapy is a promising therapeutic approach that is currently highly investigated in association to standard therapies, including RT, with the aim to improve patients' outcomes. Materials and Methods: A PubMed search was performed with the following keywords in all fields: "esophageal cancer" and "radiotherapy" and "radiation" and "immunotherapy" and "PD-1" and "PD L1." For an overview of ongoing trials, an additional search on ClinicalTrials.gov website was performed using the keywords "esophageal cancer" and "immunotherapy" and "PD-L1" and "CTLA-4" and "radiation" and "radiotherapy." Emerging data from preclinical and clinical studies are suggesting a synergistic effect between immunotherapy and RT. With the aim to update the knowledge of this synergistic immune-mediated antitumor activity and discuss current challenges, the authors summarize published data concerning the basic mechanisms and the effectiveness and tolerance of the combination between immunotherapy and RT for patients with EC, followed by an overview of ongoing clinical trial. Conclusions: Published results encourage the use of personalized therapeutic approaches for EC patients in the future; results from ongoing studies will help to identify the optimal strategies for patient selection and treatment response evaluation.

The Combination Options and Predictive Biomarkers of PD-1/PD-L1 Inhibitors in Esophageal Cancer

Esophageal cancer (EC) is one of the most common cancers with poor survival in the world. Nowadays, a generous number of clinical trials are underway on the use of immunotherapy in EC patients, especially the programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors. However, only a few patients could benefit from single-agent therapy. Others need combination therapies to enhance the response rate and survival. In this review, we focus on PD-1/PD-L1 inhibitors and its combination options in EC patients. We also summarized the potential predictive biomarkers for PD-1/PD-L1 inhibitors treatment.

Immune Checkpoint Inhibitors in Esophageal Cancers: are we Finally Finding the Right Path in the Mist?

Esophageal cancer remains a challenging disease due to limited treatment options and poor prognosis. In recent years, immune checkpoint inhibitors (ICI) have been proven to be safe and effective in the treatment of highly lethal malignancies, such as non-small cell lung cancer and melanoma. Recent clinical trials also showed promising activity in immune checkpoint inhibitors in pretreated advanced esophageal carcinoma and a potentially significant impact on the outcome of selected patients, independently of histology. Combination studies evaluating immunotherapy and chemotherapy and, in localized disease, radiotherapy are in progress and will hopefully confirm their promises in the near future. However, reliable predictive biomarkers are still lacking. Indeed, at present, the role of programmed cell death ligand 1 expression and other factors (such as microsatellite instability and tumor mutational burden) as predictive biomarkers of benefit to immune checkpoint inhibitors is still controversial. Our aim was to explore the rationale of ICIs in esophageal cancer, review the results already available in multiple settings, and investigate future perspectives with single-agent and combination strategies.

Immunotherapy with immune checkpoint inhibitors in colorectal cancer: what is the future beyond deficient mismatch-repair tumours?

Following initial success in melanoma and lung tumours, immune checkpoint inhibitors (ICIs) are now well recognized as a major immunotherapy treatment modality for multiple types of solid cancers. In colorectal cancer (CRC), the small subset that is mismatch-repair-deficient and microsatellite-instability-high (dMMR/MSI-H) derive benefit from immunotherapy; however, the vast majority of patients with proficient MMR (pMMR) or with microsatellite stable (MSS) CRC do not. Immunoscore and the consensus molecular subtype classifications are promising biomarkers in predicting therapeutic efficacy in selected CRC. In pMRR/MSS CRC, biomarkers are also needed to understand the molecular mechanisms governing immune reactivity and to predict their relationship to treatment. The continuous development of such biomarkers would offer new perspectives and more personalized treatments by targeting oncological options, including ICIs, which modify the tumour-immune microenvironment. In this review, we focus on CRC and discuss the current status of ICIs, the role of biomarkers to predict response to immunotherapy, and the approaches being explored to render pMMR/MSS CRC more immunogenic through the use of combined therapies.

Genomics and Targeted Therapies in Gastroesophageal Adenocarcinoma

Gastroesophageal adenocarcinomas (GEA) are devastating diseases with stark global presence. Over the past 10 years, there have been minimal improvements in treatment approach despite numerous clinical trials. Here, we review recent progress toward understanding the molecular features of these cancers and the diagnostic and therapeutic challenges posed by their intrinsic genomic instability and heterogeneity. We highlight the potential of genomic heterogeneity to influence clinical trial outcomes for targeted therapies and emphasize the need for comprehensive molecular profiling to guide treatment selection and adapt treatment to resistance and genomic evolution. Revising our clinical approach to GEA by leveraging genomic advances will be integral to the success of current and future treatments, especially as novel targets become therapeutically tractable. SIGNIFICANCE: GEAs are deadly cancers with few treatment options. Characterization of the genomic landscape of these cancers has revealed considerable genetic diversity and spatial heterogeneity. Understanding these fundamental properties of GEA will be critical for overcoming barriers to the development of novel, more effective therapeutic strategies.

Impact of sequential lines of palliative chemotherapy in patients with recurrent/metastatic esophageal squamous cell carcinoma: A retrospective analysis of 107 patients at a single center

AIM

This study was conducted to evaluate the efficacy of palliative chemotherapy by the lines of chemotherapy in recurrent/metastatic esophageal squamous cell carcinoma (ESCC) and to compare the efficacy between the patients with initially metastatic ESCC and those with recurrent/progressed ESCC after curative treatment.

MATERIALS AND METHODS

All 107 patients who began palliative chemotherapy for recurrent/metastatic ESCC from March 2015 to October 2017 were included, and grouped according to previous treatment: Groups A (previous chemoradiation alone, n = 30), B (previous surgery alone, n = 11), C (previous chemoradiation and surgery, n = 30), and D (initially metastatic or de novo stage IV, n = 36). Groups A, B, and C (pretreated group) and Group D (treatment-naïve group) were reorganized according to treatment history. Overall response rate (ORR) and survival data were retrospectively evaluated for each group, lines of chemotherapy, and chemotherapeutic regimen.

RESULTS

ORR was 25.2%, 7.3%, and 3.4% in first-, second-, and third-line chemotherapy, respectively. The median progression-free survival (PFS) was 4.7, 2.0, and 2.2 months in first-, second-, third-line chemotherapy, respectively. The median overall survival (OS) after first-line palliative chemotherapy was 10.1 months, and it was not significantly different between pretreated and treatment-naive groups. Previous surgery, good performance, ≥3 lines of chemotherapy, and low C-reactive protein level were linked to a significantly longer OS in multivariate analysis.

CONCLUSION

Because PFS rapidly declines with advancement of line of chemotherapy, incorporation of effective treatment modalities in early line treatments is crucial in the management of recurrent/metastatic ESCC. If tolerable, continuing advanced lines of chemotherapy may prolong survival.

Targeted Therapies and Immunotherapies in the Treatment of Esophageal Cancers

Esophageal cancer (EC) is among the most frequent and deadly cancers around the world. While esophageal adenocarcinoma (EAC) has one of the fastest-growing incidences amongst cancers in the US, it also has one of the lowest survival rates due to the limited effective treatment options. Fortunately, in the past decade, two targeted therapies and an immunotherapy agent have been approved by the FDA for metastatic EAC and esophageal squamous cell carcinoma (ESCC), with several more currently being considered for approval. In terms of immunotherapies, in July 2019, the FDA approved the PD1 inhibitor pembrolizumab for second-line treatment of PDL1-positive, advanced or metastatic ESCC. Two years before, pembrolizumab had been approved for the third-line treatment of PDL1-positive EAC. The PD1 inhibitor nivolumab, which was found in one study to outperform chemotherapy irrespective of PDL1 status, has yet to secure FDA approval. In terms of targeted therapies, although as many as 90% of EC cases show upregulated EGFR, anti-EGFR therapy has not been shown to improve survival. Ramucirumab, an antibody targeting both VEGF and HER2/neu receptors, has been approved for the treatment of refractory EAC, while the anti-HER2 monoclonal antibody (mAb) trastuzumab has been approved as front-line treatment for HER2-positive cases which account for approximately 20% of ECs. Although these targeted therapies and immunotherapies have resulted in significant improvements in survival for specific patient populations that are positive for certain biomarkers, such as PDL1 and HER2/neu, the survival rates remain low for a large proportion of the metastatic EC patient population, necessitating the development of further targeted treatment options.