Feasibility study of nivolumab as neoadjuvant chemotherapy for locally esophageal carcinoma: FRONTiER (JCOG1804E)

Neoadjuvant Chemotherapy Improves Feasibility of Larynx Preservation and Prognosis in Resectable Locally Advanced Cervical Esophageal Cancer

BACKGROUND

The optimal strategy for cervical advanced esophageal cancer remains controversial in terms of oncologic outcome as well as vocal and swallowing function. Recently, in East Asian countries, neoadjuvant chemotherapy (NAC) has been a standard strategy for advanced esophageal cancer.

METHODS

This study included 37 patients who underwent NAC, and 33 patients who underwent definitive chemoradiation therapy (dCRT) as larynx-preserving treatment for locally advanced cervical esophageal cancer from 2016 to 2021. This study retrospectively investigated outcomes, with comparison between NAC and dCRT for locally advanced cervical esophageal cancer.

RESULTS

Larynx preservation was successful for all the patients with NAC and dCRT. After NAC, the rate of complete or partial response was 78.4%, and 30 patients underwent larynx-preserving surgery. On the other hand, after dCRT, the complete response rate was 71.9%, and 4 patients underwent larynx-preserving salvage surgery. Overall survival (OS) and progression free survival were similar between the two groups. However, for the patients with resectable cervical esophageal cancer (cT1/2/3), the 2-year OS rate was significantly higher with NAC (79.9%) than with dCRT (56.8%) (P = 0.022), and the multivariate analyses identified only NAC and cN0, one of the two as a significantly independent factor associated with a better OS (NAC: P = 0.041; cN0, 1: P = 0.036).

CONCLUSION

The study showed that NAC as larynx-preserving surgery for resectable cervical esophageal cancer preserved function and had a better prognosis than dCRT. The authors suggest that NAC may be standard strategy for larynx preservation in patients with resectable cervical esophageal cancer.

Impacts of tumor microenvironment during neoadjuvant chemotherapy in patients with esophageal squamous cell carcinoma

With the advent of immune checkpoint inhibitors (ICIs), a better understanding of tumor microenvironment (TME) is becoming crucial in managing esophageal squamous cell carcinoma (ESCC) patients. We investigated the survival impact of TME status and changes in patients with ESCC who underwent neoadjuvant chemotherapy (NAC) followed by surgery (n = 264). We examined immunohistochemical status (CD4+, CD8+, CD20+, Foxp3+, HLA class-1+, CD204+, and programmed death ligand-1 [PD-L1+]) on 264 pre-NAC and 204 paired post-NAC specimens. Patients were classified by their pre- and post-NAC immune cell status and their changes following NAC. Our findings showed that pre-NAC TME status was not significantly associated with survival outcomes. In contrast, post-NAC TME status, such as low level of T cells, CD4+ T cells, and high PD-L1 combined positive score (CPS), were significantly associated with poor overall survival (OS). Notably, TME changes through NAC exerted significant survival impacts; patients with consistently low levels of T cells, low levels of CD4+ T cells, or high levels of PD-L1 (CPS) had very poor OS (3-year OS: 35.5%, 40.2%, and 33.3%, respectively). Tumor microenvironment changes of consistently low T cells, low CD4+ T cells, and high PD-L1 were independent predictors of poor OS in multivariate Cox hazards analyses, while factors indicating post-NAC status (T cells, CD4+, and PD-L1 [CPS]) alone were not. Therefore, we suggest that the consistently low T/high PD-L1 group could benefit from additional therapies, such as ICIs, and the importance of stratification by the TME, which has recently been recognized.

Oligometastases of Esophageal Squamous Cell Carcinoma: A Review

Patients with oligometastases show distant relapse in only a limited number of regions. Local therapy such as surgical resection, radiotherapy, chemoradiotherapy, and radiofrequency ablation for the relapsed sites may thus improve patient survival. Oligometastases are divided into oligo-recurrence and sync-oligometastases. Oligo-recurrence indicates a primary lesion that is controlled, and sync-oligometastases indicate a primary lesion that is not controlled. The management of oligo-recurrence and sync-oligometastases in esophageal squamous cell carcinoma has not been clearly established, and treatment outcomes remain equivocal. We reviewed 14 articles, including three phase II trials, that were limited to squamous cell carcinoma. Multimodal treatment combining surgical resection and chemoradiotherapy for oligo-recurrence of esophageal squamous cell carcinoma appears to be a promising treatment. With the development of more effective chemotherapy and regimens that combine immune checkpoint inhibitors, it will become more likely that sync-oligometastases that were unresectable at the initial diagnosis can be brought to conversion surgery. Currently, a randomized, controlled phase III trial is being conducted in Japan to compare a strategy for performing definitive chemoradiotherapy and, if necessary, salvage surgery with a strategy for conversion surgery in patients who can be resected by induction chemotherapy.

Evaluation of neoadjuvant immunotherapy in resectable gastric/gastroesophageal junction tumors: a meta-analysis and systematic review

Background

Neoadjuvant therapy for resectable gastric cancer/gastroesophageal junction tumors is progressing slowly. Although immunotherapy for advanced gastric cancer/gastroesophageal junction tumors has made great progress, the efficacy and safety of neoadjuvant immunotherapy for locally resectable gastric cancer/gastroesophageal junction tumors have not been clearly demonstrated. Here, we conducted a systematic review and meta-analysis to assess the efficacy and safety of neoadjuvant immunotherapy and advance the current research.

Methods

Original articles describing the safety and efficacy of neoadjuvant immunotherapy for resectable gastric cancer/gastroesophageal junction tumors published up until October 15, 2023 were retrieved from PubMed, Embase, the Cochrane Library, and other major databases. The odds ratios (OR) and 95% confidence intervals (CIs) were calculated for heterogeneity and subgroup analysis.

Results

A total of 1074 patients from 33 studies were included. The effectiveness of neoadjuvant immunotherapy was mainly evaluated using pathological complete remission (PCR), major pathological remission (MPR), and tumor regression grade (TRG). Among the included patients, 1015 underwent surgical treatment and 847 achieved R0 resection. Of the patients treated with neoadjuvant immunotherapy, 24% (95% CI: 19%-28%) achieved PCR and 49% (95% CI: 38%-61%) achieved MPR. Safety was assessed by a surgical resection rate of 0.89 (95% CI: 85%-93%), incidence of ≥ 3 treatment-related adverse events (TRAEs) of 28% (95% CI: 17%-40%), and incidence of ≥ 3 immune-related adverse events (irAEs) of 19% (95% CI: 11%-27%).

Conclusion

Neoadjuvant immunotherapy, especially neoadjuvant dual-immunotherapy combinations, is effective and safe for resectable gastric/gastroesophageal junction tumors in the short term. Nevertheless, further multicenter randomized trials are required to demonstrate which combination model is more beneficial.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=358752, identifier CRD42022358752.

Study on the efficacy and safety of neoadjuvant immunotherapy combined with chemotherapy regimen for III-IVA esophageal squamous cell carcinoma post-surgery

BACKGROUND AND AIMS

The treatment of esophageal squamous cell carcinoma is still controversial, and neoadjuvant chemotherapy combined with immunotherapy is a hot topic of current research. We investigated the recent efficacy and surgical safety of patients with III-IVA esophageal squamous cell carcinoma after neoadjuvant regimen of paclitaxel + cisplatin/nedaplatin/carboplatin + sindilizumab, to provide a theoretical basis for evaluating the feasibility of surgery after neoadjuvant therapy.

METHODS

The clinical data of patients with stage III-IVA esophageal squamous cell carcinoma admitted from January 2022 to April 2023 at our hospital were collected for retrospective analysis. The patients were divided into the neoadjuvant combination surgery group (34 patients with the regimen of paclitaxel + cisplatin/nedaplatin/carboplatin + sintilimab two/three cycles of preoperative neoadjuvant therapy) and surgery-only group (36 patients). Statistical analysis was performed to compare the differences between both groups particularly for intraoperative bleeding, operative time, incidence of postoperative pulmonary complications, laryngeal recurrent nerve injury, thoracic duct injury, anastomotic fistula, and postoperative hospital days. Additionally, the pCR/MPR rates of the neoadjuvant group were analysed.

RESULTS

Significant differences were present in the clinical and pathological staging before and after neoadjuvant treatment (P ≤ 0.001). The neoadjuvant group had a pCR rate of 26.47% and an ORR rate of 88.23%. No significant differences were discovered in R0 resection rate between both groups, as well as intraoperative bleeding, operative time, intraoperative laryngeal recurrent nerve injury rate, thoracic duct injury rate, postoperative anastomosis incidence, postoperative hospital days, and postoperative lung infection incidence (P > 0.05).

CONCLUSIONS

The neoadjuvant immune combination chemotherapy regimen had considerable tumor regression and pathological remission benefits, without reducing the safety of surgery, possibly presenting as a new treatment plan.

Present situation and prospect of immunotherapy for unresectable locally advanced esophageal cancer during peri-radiotherapy

Four major studies (Checkmate577, Keynote-590, Checkmate649 and Attraction-4) of locally advanced esophageal cancer published in 2020 have established the importance of immunotherapy, represented by anti-programmed death protein (PD)-1 in postoperative adjuvant treatment and advanced first-line treatment of locally advanced or advanced esophageal cancer and esophagogastric junction cancer, from the aspects of proof of concept, long-term survival, overall survival rate and progression-free survival. For unresectable or inoperable nonmetastatic esophageal cancer, concurrent radiotherapy and chemotherapy is the standard treatment recommended by various guidelines. Because its curative effect is still not ideal, it is necessary to explore radical radiotherapy and chemotherapy in the future, and it is considered to be promising to combine them with immunotherapeutic drugs such as anti-PD-1. This paper mainly discusses how to combine radical concurrent radiotherapy and chemotherapy with immunotherapy for unresectable local advanced esophageal cancer.

Long-term efficacy and predictors of pembrolizumab-based regimens in patients with advanced esophageal cancer in the real world

BACKGROUND

Pembrolizumab combined with chemotherapy has been proven effective as first-line therapy in patients with advanced esophageal cancer. Few trials have assessed the safety and efficacy of this treatment in patients with locally advanced disease.

AIM

To analyze long-term outcomes of pembrolizumab in locally advanced or metastatic esophageal squamous cell carcinoma (ESCC) in the real world.

METHODS

Patients with advanced ESCC admitted to our center from October 2019 to October 2021 were enrolled in this study. Clinical staging of the patients was based on the 8th edition of the American Joint Committee on Cancer TNM staging system. The patients received different treatments based on clinical stage. In brief, patients with locally advanced and resectable ESCC received neoadjuvant therapy combined with surgery. For those who were not candidates for resection, radical concurrent chemoradiotherapy plus pembrolizumab was more preferable. Patients with metastatic ESCC or who were unsuitable for radiotherapy underwent chemotherapy in combination with pembrolizumab. Long-term survival outcomes such as overall survival (OS), progression-free survival, disease-free survival, long-term adverse effects (AEs), immune maintenance therapy and predictors of immune checkpoint inhibitors (ICIs) efficacy were evaluated.

RESULTS

A total of 55 patients with advanced ESCC were enrolled in this retrospective, observational study. The median age was 61 years (range 44-74), with 47.3% (26/55) of the patients in stage IV and 45.5% of the patients had the tumor (25/55) located in the middle third of the esophagus. The median OS in all patients was not reached. The 12-mo OS rate among all patients was 78.8% and the 18-mo OS rate was 72.7%. 9 patients died due to tumor progression and 7 patients died due to treatment-related complications. The therapeutic effect evaluated at the interim evaluation was significantly reflected in the long-term outcome. Patients with complete response or partial response in all patients (P = 0.005) and in the chemoradiotherapy plus pembrolizumab group (P = 0.007) obtained a better prognosis than non-responders. A total of 20 patients (20/55, 36%) received immune maintenance therapy. Baseline peripheral blood biomarkers of the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and neutrophil-to-(leukocyte-neutrophil) ratio did not predict the efficacy of ICIs.

CONCLUSION

Pembrolizumab combined with chemotherapy or radiotherapy resulted in favorable long-term survival in patients with locally advanced or metastatic ESCC, with safe and manageable long-term AEs.

Perioperative immunotherapy for esophageal squamous cell carcinoma: Now and future

Esophageal cancer (EC) ranks among the most prevalent malignant tumors affecting the digestive tract. Esophageal squamous cell carcinoma (ESCC) stands as the prevailing pathological subtype, encompassing approximately 90% of all EC patients. In clinical stage II-IVA locally advanced ESCC cases, the primary approach to treatment involves a combination of neoadjuvant therapy and surgical resection. Despite concerted efforts, the long-term outcomes for ESCC patients remain unsatisfactory, with dismal prognoses. However, recent years have witnessed remarkable strides in immunotherapy, particularly in the second- and first-line treatment of advanced or metastatic ESCC, with the development of monoclonal antibodies that inhibit programmed death 1 or programmed death ligand 1 demonstrating encouraging responses and perioperative clinical benefits for various malignancies, including ESCC. This comprehensive review aims to present the current landscape of perioperative immunotherapy for resectable ESCC, focusing specifically on the role of immune checkpoint inhibitors during the perioperative period. Additionally, the review will explore promising biomarkers and offer insights into future prospects.

Current neoadjuvant therapy for operable locally advanced esophageal cancer

Locally advanced esophageal cancer has a poor prognosis, while an increasing number of patients are diagnosed with that. Neoadjuvant therapy has become a hot topic in treating locally advanced esophageal cancer to improve its survival benefit. The efficacy of neoadjuvant therapy followed by surgery has been confirmed by many studies, and neoadjuvant chemoradiotherapy and neoadjuvant chemotherapy are included in the guidelines. In recent years, targeted therapy and immunotherapy have emerged, and more studies are evaluating the efficacy of combining them with neoadjuvant therapy for operable esophageal cancer patients. Even though the preliminary data is disappointing, many trials are still under investigation without improving survival benefits. New indexes used as surrogate endpoints (e.g., major pathologic response and pathological complete response) are emerging to accelerate the development and approval of neoadjuvant drugs. This review summarized the research progress in neoadjuvant therapy for locally advanced esophageal cancer and discussed which primary endpoint should be used in neoadjuvant therapy trials.

Real-world Evaluation of the Efficacy of Neoadjuvant DCF Over CF in Esophageal Squamous Cell Carcinoma: Propensity Score-matched Analysis From 85 Authorized Institutes for Esophageal Cancer in Japan

OBJECTIVE

We aimed to evaluate the efficacy of neoadjuvant docetaxel, cisplatin, and 5-fluorouracil (DCF) therapy over cisplatin and 5-fluorouracil (CF) in patients with surgically resectable advanced esophageal squamous cell carcinoma (ESCC), using real-world data from 85 esophageal centers.

BACKGROUND

JCOG1109 trial, which assessed the superiority of DCF over CF, and the superiority of chemoradiotherapy with CF over CF alone demonstrated the significant survival advantage of neoadjuvant DCF in overall survival (OS) over CF for ESCC.

METHODS

The ESCC patients who received neoadjuvant CF or DCF at 85 Japanese esophageal centers certified by the Japan Esophageal Society were retrospectively reviewed. After propensity score (PS) matching, the OS and recurrence-free survival were compared between CF and DCF.

RESULTS

We initially enrolled 4781 patients. After data cleaning and PS matching using pretreatment variables, 1074 patients for each group were selected for subsequent analysis. There was no significant difference in the incidence of postoperative pneumonia and anastomotic leakage. In the survival analysis, OS was significantly longer in DCF group than CF group (hazard ratio, 0.868; 95% confidence interval, 0.770-0.978; P =0.02), as well as recurrence-free survival (hazard ratio, 0.850; 95% confidence interval, 0.761-0.949; P =0.004). The survival advantage of DCF was not observed in patients with 76 years old or older.

CONCLUSIONS

Neoadjuvant DCF therapy showed a remarkable survival advantage in surgically resectable ESCC patients, especially in patients who were 75 years old or younger. The current real-world evidence will encourage recommendations for DCF as a standard regimen in neoadjuvant chemotherapy-based treatment strategy for ESCC.

PLEK2 and IFI6, representing mesenchymal and immune-suppressive microenvironment, predicts resistance to neoadjuvant immunotherapy in esophageal squamous cell carcinoma

BACKGROUND

Immunotherapy has largely improved clinical outcome of patients with esophageal squamous cell carcinoma (ESCC). However, a proportion of patients still fail to benefit. Thus, biomarkers predicting therapeutic resistance and underlying mechanism needs to be investigated.

METHODS

Transcriptomic profiling was applied in FFPE tissues from 103 ESCC patients, including surgical samples from 66 treatment-naïve patients with long-term follow-up, and endoscopic biopsies from 37 local advanced ESCC cases receiving neoadjuvant immunotherapy plus chemotherapy. Unsupervised clustering indicated an aggressive phenotype with mesenchymal character in 66 treatment-naïve samples. Univariant logistic regression was applied to identify candidate biomarkers potentially predicted resistance to neoadjuvant immunotherapy within the range of mesenchymal phenotype enriched genes. These biomarkers were further validated by immunohistochemistry. Putative mechanisms mediating immunotherapy resistance, as indicated by microenvironment and immune cell infiltration, were evaluated by transcriptomic data, and validated by multiplex immunofluorescence.

RESULTS

PLEK2 and IFI6, highly expressed in mesenchymal phenotype, were identified as novel biomarkers relating to non-MPR in neoadjuvant immunotherapy cohort [PLEK2^high, OR (95% CI): 2.15 (1.07-4.33), P = 0.032; IFI6^high, OR (95% CI): 2.21 (1.16-4.23), P = 0.016). PLEK2^high and IFI6 ^high ESCC patients (versus low expressed patients) further exhibit higher chance of non-major pathological remissions (90%, P = 0.004) in neoadjuvant immunotherapy cohort and high mortality (78.9%, P = 0.05), poor prognosis in retrospective cohort. PLEK2^high/IFI6^high ESCC recapitulated mesenchymal phenotype, characterized by extracellular matrix composition and matrix remodeling. In addition, PLEK2^high or IFI6^high ESCC displayed an immune-unfavored microenvironment, represented by positive correlating with regulatory T cells, Helper 2 T cell as well as less infiltration of B cells, effector T cells and mast cells.

CONCLUSIONS

PLEK2 and IFI6 was discovered of first time to identify a distinct ESCC subpopulation cannot be benefited from neoadjuvant immunotherapy and present a poor survival, which putatively associated with mesenchymal and immune-suppressive microenvironment.

Comparing a PD-L1 inhibitor plus chemotherapy to chemotherapy alone in neoadjuvant therapy for locally advanced ESCC: a randomized Phase II clinical trial : A randomized clinical trial of neoadjuvant therapy for ESCC

BACKGROUND

A Phase II study was undertaken to evaluate the safety and efficacy of the neoadjuvant socazolimab, a novel PD-L1 inhibitor, in combination with nab-paclitaxel and cisplatin for locally advanced esophageal squamous cell carcinoma (ESCC).

METHODS

Sixty-four patients were randomly divided between the Socazolimab + nab-paclitaxel + cisplatin (TP) arm (n = 32) and the control arm (n = 32), receiving either socazolimab (5 mg/kg intravenously (IV), day 1) or a placebo with nab-paclitaxel (125 mg/m² IV, day 1/8) and cisplatin (75 mg/m² IV, day 1) repeated every 21 days for four cycles before surgery. The primary endpoint was major pathological response (MPR), and the secondary endpoints were pathological complete response (pCR), R0 resection rate, event-free survival (EFS), overall survival (OS), and safety.

RESULTS

A total of 29 (90.6%) patients in each arm underwent surgery, and 29 (100%) and 28 (98.6%) patients underwent R0 resection in the Socazolimab + TP and Placebo + TP arms, respectively. The MPR rates were 69.0 and 62.1% (95% Confidence Interval (CI): 49.1-84.0% vs. 42.4-78.7%, P = 0.509), and the pCR rates were 41.4 and 27.6% (95% CI: 24.1-60.9% vs. 13.5-47.5%, P = 0.311) in the Socazolimab + TP and Placebo + TP arms, respectively. Significantly higher incidence rates of ypT0 (37.9% vs. 3.5%; P = 0.001) and T downstaging were observed in the Socazolimab + TP arm than in the Placebo + TP arm. The EFS and OS outcomes were not mature.

CONCLUSIONS

The neoadjuvant socazolimab combined with chemotherapy demonstrated promising MPR and pCR rates and significant T downstaging in locally advanced ESCC without increasing surgical complication rates.

TRIAL REGISTRATION

Registration name (on clinicaltrials.gov): A Study of Anti-PD-L1 Antibody in Neoadjuvant Chemotherapy of Esophageal Squamous Cell Carcinoma.

REGISTRATION NUMBER

NCT04460066.

Impact of Perineural Invasion and Preexisting Type 2 Diabetes on Patients with Esophageal Squamous Cell Carcinoma Receiving Neoadjuvant Chemoradiotherapy

Neoadjuvant chemoradiotherapy (neoCRT) followed by surgery is the cornerstone treatment strategy in locally advanced esophageal squamous cell carcinoma (ESCC). Despite this high- intensity multimodality therapy, most patients still experience recurrences and metastases, especially those who do not achieve a pathological complete response (pCR) after neoCRT. Here, we focused on identifying poor prognostic factors. In this retrospective cohort study; we enrolled 140 patients who completed neoCRT plus surgery treatment sequence with no interval metastasis. Overall, 45 of 140 patients (32.1%) achieved a pCR. The overall survival, disease-free survival (DFS), and metastasis-free survival was significantly better in patients with a pCR than in patients with a non-pCR. In the non-pCR subgroup, the presence of perineural invasion (PNI) and preexisting type 2 diabetes (T2DM) were two factors adversely affecting DFS. After adjusting for other factors, multivariate analysis showed that the hazard ratio (HR) was 2.354 (95% confidence interval [CI] 1.240-4.467, p = 0.009) for the presence of PNI and 2.368 (95% CI 1.351-4.150, p = 0.003) for preexisting T2DM. Patients with a combination of both factors had the worst survival. In conclusion, PNI and preexisting T2DM may adversely affect the prognosis of patients with ESCC receiving neoadjuvant chemoradiotherapy.

The Molecular Characterization of Genetic Abnormalities in Esophageal Squamous Cell Carcinoma May Foster the Development of Targeted Therapies

Esophageal cancer is among the most common tumors in the world and is associated with poor outcomes, with a 5-year survival rate of about 10-20%. Two main histological subtypes are observed: esophageal squamous cell carcinoma (ESCC), more frequent among Asian populations, and esophageal adenocarcinoma (EAC), the predominant type in Western populations. The development of molecular analysis techniques has led to the definition of the molecular alterations observed in ESCC, consistently differing from those observed in EAC. The genetic alterations observed are complex and heterogeneous and involve gene mutations, gene deletions and gene amplifications. However, despite the consistent progress in the definition of the molecular basis of ESCC, precision oncology for these patients is still virtually absent. The recent identification of molecular subtypes of ESCC with clinical relevance may foster the development of new therapeutic strategies. It is estimated that about 40% of the genetic alterations observed in ESCC are actionable. Furthermore, the recent introduction of solid tumor immunotherapy with immune checkpoint inhibitors (ICIs) showed that a minority of ESCC patients are responsive, and the administration of ICIs, in combination with standard chemotherapy, significantly improves overall survival over chemotherapy in ESCC patients with advanced disease.

Docetaxel+Cisplatin+5-FU (DCF) Therapy as a Preoperative Chemotherapy to Advanced Esophageal Squamous Cell Carcinoma: A Single-center Retrospective Cohort Study

Objective The aim of this study was to determine the safety and clinical efficacy of docetaxel+cisplatin+5-fluorouracil (DCF) as neoadjuvant chemotherapy (NAC). Methods In this single-center study, patient background and treatment outcomes (NAC efficacy assessment, NAC adverse events, short-term postoperative outcomes, and one-year postoperative outcomes) in patients treated with preoperative DCF and preoperative cisplatin+5-FU (CF) were compared retrospectively. Patients Seventeen patients diagnosed with esophageal squamous cell carcinoma (ESCC) and treated with preoperative DCF therapy and 50 patients treated with preoperative CF therapy between January 2013 and July 2019 were included in this study. Results There were significant differences in clinical T factor and clinical stage between the CF and DCF groups (p<0.05). All patients in the DCF therapy group were above clinical T3 and clinical stage III. The clinical response after NAC was partial response (PR) for 23 patients (46.0%) in the CF group and 13 patients (76.5%) in the DCF group (p=0.030). Regarding adverse events in NAC, neutropenia, febrile neutropenia (FN), diarrhea, and stomatitis were observed more frequently in the DCF group than in the CF group (p<0.05). The postoperative results [overall survival (OS), recurrence-free survival (RFS), one-year OS, one-year RFS] of the DCF group were comparable to those of the CF group. Conclusion DCF therapy has been recognized as an effective treatment option for advanced ESCC. However, the indication for DCF therapy should be chosen carefully because of the high incidence of adverse events.

Profile of Nivolumab in the Treatment of Resected Esophageal Squamous Cell Carcinoma: A Review of the Clinical Data

Esophageal cancer (EC) is the seventh most common malignancy globally. There are two main histological subtypes: esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma. ESCC is the predominant histological type of esophageal cancer worldwide and has worse prognosis than esophageal adenocarcinoma. However, effective treatment for patients with ESCC remains limited. Moreover, the risk of recurrence remains high in patients with resectable ESCC even with perioperative multidisciplinary treatment, such as chemoradiotherapy or chemotherapy. Nivolumab, a human monoclonal immunoglobulin G4 antibody that inhibits programmed cell death protein 1, has recently been identified as a potential treatment for patients with metastatic esophageal cancer based on the results of the ATTRACTION-3 and CheckMate 648 trials. The CheckMate 577 trial showed survival benefits of postoperative nivolumab monotherapy compared with placebo in patients with resectable locally advanced esophageal cancer who did not achieve a pathological complete response after preoperative chemoradiotherapy. In this review, we discuss the data on the efficacy and safety of postoperative nivolumab and share future perspectives on immune checkpoint inhibitors as perioperative therapy for patients with locally advanced ESCC.

Immune checkpoint inhibitors in esophageal cancer: Clinical development and perspectives

Esophageal cancer is the sixth most common cause of cancer-related mortality worldwide. The standard treatment for unresectable esophageal cancer is systemic chemotherapy. However, the survival benefit is limited, with a median overall survival of less than 10 months. The advent of immune checkpoint inhibitors (ICIs), including programmed cell death-1 antibodies, has revolutionized the treatment paradigm for esophageal cancer. Since demonstrating promising efficacy with manageable safety in several clinical trials, ICIs has finally reached the point where they can be used in various tumor stages in the clinical setting. ICIs are most promising treatments that can be expected to improve the prognosis in patients with esophageal cancer now and in the future. This review outlines the mechanisms, results of clinical trials, and prospects for future studies of ICIs in esophageal cancer. It also discusses clinical questions and challenges in the therapeutic development of ICIs.

IGFBP1hiWNT3Alo Subtype in Esophageal Cancer Predicts Response and Prolonged Survival with PD-(L)1 Inhibitor

PD-(L)1 inhibitor could improve the survival of locally advanced esophageal cancer (ESCA) patients, but we cannot tailor the treatment to common biomarkers. WNT signaling activation was associated with primary resistance to immunotherapy. In this study, we used our two clinical cohorts (BJCH n = 95, BJIM n = 21) and three public cohorts to evaluate and verify a new immunotherapeutic biomarker based on WNT signaling in ESCA patients. Our findings showed that WNT signaling-related genes stratified TCGA patients into Cluster 1, 2, and 3, among which, Cluster 3 had the worst prognosis. The most up- and down-regulated genes in Cluster 3 were IGFBP1 and WNT3A. Further analysis validated that IGFBP1^hiWNT3A^lo ESCA patients had significantly poor RFS and OS in the TCGA and BJCH cohorts. Interestingly, IGFBP1^hiWNT3A^lo patients had a good response and prognosis with immunotherapy in three independent cohorts, exhibiting better predictive value than PD-L1 expression (signature AUC = 0.750; PD-L1 AUC = 0.571). Moreover, IGFBP1^hiWNT3A^lo patients may benefit more from immunotherapy than standard treatment (p = 0.026). Immune cell infiltration analysis revealed a significant increase in DC infiltration in IGFBP1^hiWNT3A^lo patients post-immunotherapy (p = 0.022), which may enhance immune response. The IGFBP1^hiWNT3A^lo signature could predict patients who benefited from PD-(L)1 inhibitor treatment and may serve as a biomarker in ESCA.

Recent Advances in Combination of Immunotherapy and Chemoradiotherapy for Locally Advanced Esophageal Squamous Cell Carcinoma

Simple Summary

Neoadjuvant chemoradiotherapy (CRT), followed by surgery or definitive CRT, is the standard treatment for locally advanced esophageal squamous cell carcinoma (ESCC); however, the clinical outcomes remain unsatisfactory. Immunotherapy combined with CRT is currently being investigated as a novel treatment option for locally advanced ESCC. In this review, we discuss the theoretical background and status of immunotherapy for locally advanced ESCC and potential biomarkers for predicting tumor response and prognosis.

Abstract

Esophageal cancer has a high mortality rate and a poor prognosis, with more than one-third of patients receiving a diagnosis of locally advanced cancer. Esophageal squamous cell carcinoma (ESCC) is the dominant histological subtype of esophageal cancer in Asia and Eastern Europe. Although neoadjuvant or definitive chemoradiotherapy (CRT) has been the standard treatment for locally advanced ESCC, patient outcomes remain unsatisfactory, with recurrence rates as high as 30–50%. The combination of immune checkpoint inhibitors (ICIs) and CRT has emerged as a novel strategy to treat esophageal cancer, and it may have a synergistic action and provide greater efficacy. In the phase III CheckMate-577 trial, one year of adjuvant nivolumab after neoadjuvant CRT improved disease-free survival in patients with residual disease on pathology. Moreover, several phase I and II studies have shown that ICIs combined with concurrent CRT may increase the rate of pathologic complete response for resectable ESCC, but they lack long-term follow-up results. In unresectable cases, the combination of camrelizumab and definitive CRT showed promising results against ESCC in a phase Ib trial. Phase III randomized trials are currently ongoing to investigate the survival benefits of ICIs combined with neoadjuvant or definitive CRT, and they will clarify the role of immunotherapy in locally advanced ESCC. Additionally, valid biomarkers to predict tumor response and survival outcomes need to be further explored.

Efficacy and safety of neoadjuvant immunotherapy combined with chemotherapy in locally advanced esophageal cancer: A meta-analysis

Objective

The progress of neoadjuvant therapy for resectable locally advanced esophageal cancer has been stagnant. There has been much progress in immunotherapy for advanced esophageal cancer, but the efficacy and safety of neoadjuvant immunotherapy for resectable locally advanced esophageal cancer have not yet been definitively demonstrated.

Methods

Original articles describing the safety and efficacy of neoadjuvant immunotherapy in resectable locally advanced esophagus published until July 2022 were retrieved from PubMed, Embase, and the Cochrane Library. The ratio (OR) and 95% confidence interval (CI) were calculated to conduct heterogeneity and subgroup analysis.

Results

In total, 759 patients from 21 studies were enrolled. The effectiveness of neoadjuvant immunotherapy in combination with chemotherapy was evaluated using the major pathologic response (MPR) and pathologic complete response (PCR). In the enrolled patients, 677 were treated surgically and 664 achieved R0 resection. Major pathological remission was achieved in 52.0% (95% CI: 0.44–0.57) of patients on neoadjuvant immunotherapy combined with chemotherapy and complete pathological remission in 29.5% (95% CI: 0.25–0.32) of patients. The safety was primarily assessed by the incidence of treatment-related adverse events (TRAEs) and surgical resection rates. The incidence of TRAEs and the surgical resection rate combined ORs were 0.15 (95% CI: 0.09–0.22) and 0.86 (95% CI: 0.83–0.89), respectively.

Conclusion

Neoadjuvant immunotherapy combined with chemotherapy in locally advanced resectable esophageal cancer is effective and safe.

Current perspectives of the Japanese Esophageal Oncology Group on the development of immunotherapy for esophageal cancer

Esophageal cancer is the seventh most common cancer worldwide and continues to have a poor prognosis. Starting with the development of immune checkpoint inhibitors for patients with metastatic melanoma, many clinical trials have been conducted to evaluate the efficacy and safety of immune checkpoint inhibitors against various malignancies. Although few effective drugs are available for patients with advanced esophageal cancer, two immune checkpoint inhibitors, nivolumab and pembrolizumab, have been approved as second-line treatments for advanced esophageal squamous cell carcinoma. Recently, immune checkpoint inhibitors have shown promising results as post-operative therapies and first-line treatments for advanced esophageal cancer. Nivolumab has been approved as a post-operative therapy based on the CheckMate-577 trial, and nivolumab, ipilimumab and pembrolizumab have been approved as first-line treatments based on the CheckMate-648 trial and the KEYNOTE-590 trial. In addition, many trials of immune checkpoint inhibitors plus pre-operative treatment or definitive chemoradiotherapy are ongoing. The Japan Esophageal Oncology Group was established in 1978 and has conducted numerous clinical trials, most of which have examined multimodality treatments. In the era of immunotherapy, Japan Esophageal Oncology Group is conducting a clinical trial studying multimodality treatment with an immune checkpoint inhibitor. JCOG1804E (FRONTiER) is a phase I trial to evaluate the safety and efficacy of nivolumab plus pre-operative chemotherapy followed by surgery. These results might improve the clinical outcomes of esophageal cancer patients.

The Role of the Heat-Shock Proteins in Esophagogastric Cancer

Heat-shock proteins (HSPs) are a family of proteins that have received considerable attention over the last several years. They have been classified into six prominent families: high-molecular-mass HSP, 90, 70, 60, 40, and small heat shock proteins. HSPs participate in protein folding, stability, and maturation of several proteins during stress, such as in heat, oxidative stress, fever, and inflammation. Due to the immunogenic host’s role in the combat against cancer cells and the role of the inflammation in the cancer control or progression, abnormal expression of these proteins has been associated with many types of cancer, including esophagogastric cancer. This study aims to review all the evidence concerning the role of HSPs in the pathogenesis and prognosis of esophagogastric cancer and their potential role in future treatment options. This narrative review gathers scientific evidence concerning HSPs in relation to esophagus and gastric cancer. All esophagogastric cancer subtypes are included. The role of HSPs in carcinogenesis, prognostication, and therapy for esophagogastric cancer are discussed. The main topics covered are premalignant conditions for gastric cancer atrophic gastritis, Barrett esophagus, and some viral infections such as human papillomavirus (HPV) and Epstein–Barr virus (EBV). HSPs represent new perspectives on the development, prognostication, and treatment of esophagogastric cancer.

Transcriptomic datasets of cancer patients treated with immune-checkpoint inhibitors: a systematic review

The availability of immune-checkpoint inhibitors (ICI) in the last decade has resulted in a paradigm shift in certain areas of oncology. Patients can be treated either by a monotherapy of anti-CTLA-4 (tremelimumab or ipilimumab), anti-PD-1 (nivolumab or pembrolizumab), or anti-PD-L1 (avelumab or atezolizumab or durvalumab) or as combination therapy of anti-CTLA-4 and anti-PD-1. To maximize the clinical treatment benefit of cancer immunotherapy, the prediction of the actual immune response by the identification and application of clinically useful biomarkers will be required. Whole transcriptomic datasets of patients with ICI treatment could provide the basis for large-scale discovery and ranking of such potential biomarker candidates. In this review, we summarize currently available transcriptomic data from different biological sources (whole blood, fresh-frozen tissue, FFPE) obtained by different methods (microarray, RNA-Seq, RT-qPCR). We directly include only results from clinical trials and other investigations where an ICI treatment was administered. The available datasets are grouped based on the administered treatment and we also summarize the most important results in the individual cohorts. We discuss the limitations and shortcomings of the available datasets. Finally, a subset of animal studies is reviewed to provide an overview of potential in vivo ICI investigations. Our review can provide a swift reference for researchers aiming to find the most suitable study for their investigation, thus saving a significant amount of time.

Maximum standardized uptake value change rate before and after neoadjuvant chemotherapy can predict early recurrence in patients with locally advanced esophageal cancer: a multi-institutional cohort study of 220 patients in Japan

BACKGROUND

Neoadjuvant chemotherapy (NAC) followed by esophagectomy can improve the prognosis of locally advanced esophageal cancer (LAEC). However, LAEC reportedly recurred in 17-21% of patients within 6 months post surgery. Thus, current treatment strategies may be inadequate for LAECs with poor prognosis. Preoperative identification of patients with poor prognosis might aid in modification of treatment strategies. This study aimed to evaluate the usefulness of the maximum standardized uptake value change rate (ΔSUV_max) in predicting treatment effects on the primary lesion, prognosis, and LAEC recurrence.

METHODS

This study involved 220 esophageal cancer patients who underwent esophagectomy after NAC at three facilities in Japan. The optimal cut-off point for ΔSUV_max in predicting tumor regression grade (TRG) was calculated and used to assess the correlation between ΔSUV_max and postoperative survival.

RESULTS

The optimal cut-off point for ΔSUV_max was 0.5. The 5-year overall survival rate in patients with ΔSUV_max ≥ 0.5 was significantly higher than that in patients with ΔSUV_max < 0.5 (71.5% vs. 50.5%, P = 0.001). Multivariate analysis identified ΔSUV_max (hazards ratio, 0.496; P = 0.004) as an independent prognostic factor. Among 199 patients evaluated for recurrence, 24 (12.1%) showed recurrence within 6 months post surgery. Univariate analysis revealed ΔSUV_max as the only predictor for early recurrence (odds ratio, 0.222; P = 0.004).

CONCLUSION

ΔSUV_max before and after NAC is clinically useful as it could help predict TRG, survival outcome, and early recurrence within 6 months post esophagectomy and is easily obtainable in general clinical practice. We believe that it may also help determine suitable treatment strategies for LAEC.

Combining serum inflammation indexes at baseline and post treatment could predict pathological efficacy to anti‑PD‑1 combined with neoadjuvant chemotherapy in esophageal squamous cell carcinoma

Background

The neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) have been used to predict therapeutic response in different tumors. However, no assessments of their usefulness have been performed in esophageal squamous cell carcinoma (ESCC) patients receiving anti‑PD‑1 combined with neoadjuvant chemotherapy.

Methods

The respective data of 64 ESCC patients receiving anti‑PD‑1 combined with neoadjuvant chemotherapy were analyzed. Whether NLR, LMR, PLR, and SII at baseline and post-treatment might predict pathological response to anti‑PD‑1 plus neoadjuvant chemotherapy, and cutoff values of these parameters were all determined by ROC curve analysis.

Results

NLR (cutoff = 3.173, AUC = 0.644, 95% CI 0.500–0.788, P = 0.124, sensitivity = 1.000, specificity = 0.373), LMR (cutoff = 1.622, AUC = 0.631, 95% CI 0.477–0.784, P = 0.161, sensitivity = 0.917, specificity = 0.137), PLR (cutoff = 71.108, AUC = 0.712, 95% CI 0.575–0.849, P = 0.023, sensitivity = 1.000, specificity = 0.059), and SII at baseline (cutoff = 559.266, AUC = 0.681, 95% CI 0.533–0.830, P = 0.052, sensitivity = 0.373, specificity = 1.000) seemed to be a useful predictor for distinguishing responders from non-responders. Combining NLR with SII at baseline (AUC = 0.729, 95% CI 0.600–0.858, P = 0.014, sensitivity = 0.917, specificity = 0.510), LMR and SII at baseline (AUC = 0.735, 95% CI 0.609–0.861, P = 0.012, sensitivity = 1.000 specificity = 0.471), PLR and SII at baseline (AUC = 0.716, 95% CI 0.584–0.847, P = 0.021, sensitivity = 1.000 specificity = 0.431), and LMR and PLR at post-treatment in the third period (AUC = 0.761, 95% CI 0.605–0.917, P = 0.010, sensitivity = 0.800, specificity = 0.696) might slightly increase the prediction ability to determine patients who have response or no response. Finally, combining LMR at baseline, SII at post-treatment in the second period with PLR at post-treatment in the third period could be considered a better predictor for discriminating responders and non-responders than single or dual biomarkers (AUC = 0.879, 95% CI 0.788–0.969, P = 0.0001, sensitivity = 0.909, specificity = 0.800).

Conclusions

The models we constructed allowed for the accurate and efficient stratification of ESCC patients receiving anti-PD-1 plus chemotherapy and are easily applicable for clinical practice at no additional cost.

Role sharing between minimally invasive oesophagectomy and organ preservation approach for surgically resectable advanced oesophageal cancer

Oesophageal cancer is a dismal disease since it metastasizes widely even from an early stage. In order to improve treatment outcomes, multidisciplinary treatments including surgery, chemotherapy and radiotherapy have been developed. While oesophagectomy is the mainstay in the treatment strategy, it is highly invasive since it requires two to three field approaches. To reduce surgical stress and morbidity, minimally invasive oesophagectomy including thoracoscopy, robotic assisted surgery and mediastinoscopy were introduced. Various clinical trials proved that these techniques decrease the post-operative morbidity rate. Furthermore, with the advancement of multidisciplinary treatment with a higher response rate, the possibility arose for omission of surgical resection in remarkable responders to neoadjuvant therapy. However, in order to safely provide organ preservation without increasing the risk of post-treatment recurrence, an accurate tumour monitoring system is required. Although endoscopy and computed tomography imaging have been a standard, the detection rate of residual tumours after treatment is still unsatisfactory. Utilizing liquid biopsy which could evaluate tumour derivative and host response, an appropriate monitoring system of tumour burden during multidisciplinary treatment can be developed. With the advancement of minimally invasive surgery and multidisciplinary treatment, the treatment strategy needs to be highly individualized based on the tumour biology, patients' condition and their preferences. Along with the improvement of the tumour monitoring system, appropriate role sharing can be achieved between a minimally invasive surgery and the organ preservation approach.

Neoadjuvant camrelizumab plus chemotherapy in treating locally advanced esophageal squamous cell carcinoma patients: a pilot study

Background

Camrelizumab (a PD-1 inhibitor) has been used as a potential therapy in unresectable advanced esophageal squamous cell carcinoma (ESCC) along with adjuvant treatment in locally advanced ESCC, exhibiting an acceptable efficacy and safety profile. This pilot study was designed to further investigate the clinical value and tolerance of neoadjuvant camrelizumab plus chemotherapy in locally advanced ESCC.

Methods

A total of 16 patients with locally advanced ESCC were recruited. Patients received 2 cycles of neoadjuvant therapy including 2 doses of camrelizumab concurrent with 2 cycles of paclitaxel plus carboplatin followed by surgery 4 weeks afterward. Then, the treatment response after neoadjuvant therapy, R0 resection rate, tumor regression grade (TRG), and pathological complete remission (pCR) rate were measured. Besides, adverse events were documented. At last, progression-free survival (PFS) and overall survival (OS) were assessed.

Results

Generally, objective remission rate (ORR) was 81.3% whereas disease control rate (DCR) was 100% after neoadjuvant therapy. Concerning TRG grade, 31.3, 37.5, 18.8, and 12.5% patients reached TRG0, TRG1, TRG2, and TRG3, respectively. Then, pCR rate and R0 resection rate were 31.3 and 93.8%, respectively. Besides, mean PFS and OS were 18.3 months (95%CI: (16.2–20.5) months) and 19.2 months (95%CI: (17.7–20.7) months), respectively, with a 1-year PFS of 83% and OS of 90.9%. Adverse events included white blood cell decrease (37.5%), neutrophil decrease (31.3%), reactive cutaneous capillary endothelial proliferation (37.5%), and nausea or vomiting (25.0%), which were relatively mild and manageable.

Conclusion

Neoadjuvant camrelizumab plus chemotherapy exhibits good efficacy and acceptable tolerance in patients with locally advanced ESCC.

Comparison of efficacy and safety between pembrolizumab combined with chemotherapy and simple chemotherapy in neoadjuvant therapy for esophageal squamous cell carcinoma

BACKGROUND

Immunotherapy can activate the recognition of tumor antigen, build immune memory, and more and more clinical trials have taken the scheme of immunochemotherapy or immunoradiotherapy as a treatment strategy for esophageal squamous cell carcinoma (ESCC). Our objective was to compare the efficacy and safety between pembrolizumab combined with the chemotherapy group and simple chemotherapy in neoadjuvant therapy of ESCC.

METHODS

Fifty-four ESCC patients with stage II-IVa were enrolled at the Fifth Affiliated Hospital of Sun Yat-sen University between January 2018 and December 2020, including 23 in the pembrolizumab combined with chemotherapy group (combined group), and 31 in the simple chemotherapy group. All patients received radical surgical treatment after two cycles of neoadjuvant therapy.

RESULTS

The pathological complete response (pCR) and objective response rate (ORR) in the combined group were significantly higher than that of the simple chemotherapy group (30.4% vs. 9.7%, P=0.048; 86.9% vs. 95.7%, P=0.017) as well as the score of tumor regression ≥2 (80.7% vs. 50.0%, P=0.013). And the complete rate of esophagectomy and R0 /R1 resection rate in the two groups were not statistically significant. Otherwise, the incidence of adverse events in the combined group was similar compared with the simple chemotherapy group.

CONCLUSIONS

Pembrolizumab combined with chemotherapy showed promising activity with a manageable safety profile. And it could offer a potential new neoadjuvant treatment approach for patients with ESCC.

Emerging data on nivolumab for esophageal squamous cell carcinoma

INTRODUCTION

Esophageal cancer (EC) is the seventh most common malignancy in the world. The standard treatment for advanced EC patients is systemic chemotherapy, but few effective cytotoxic agents are available. Recently, nivolumab, a human monoclonal immunoglobulin G4 antibody that inhibits programmed cell death protein 1, has been tested for the treatment of advanced squamous cell carcinoma (ESCC) patients. The ATTRACTION-1 trial showed a promising efficacy of nivolumab monotherapy for advanced ESCC patients after prior chemotherapy. The ATTRACTION-3 phase III trial showed the superiority of nivolumab monotherapy over taxane monotherapy for advanced ESCC patients as a second-line treatment. The CheckMate-577 trial also showed survival benefits of postoperative nivolumab monotherapy in patients with resectable EC.

AREAS COVERED

This review mainly outlines emerging data on nivolumab for patients with advanced ESCC after prior chemotherapy. Additionally, this review includes data from the CheckMate-577 trial for patients with resectable EC.

EXPERT OPINION

Nivolumab has been approved by the US Food and Drug Administration for treatment after prior chemotherapy in patients with advanced ESCC. Several trials evaluating nivolumab-containing treatments are ongoing in patients with not only advanced EC, but also locally advanced EC, and these investigational treatments might improve the clinical outcomes of EC patients.

RATIONALE 311: tislelizumab plus concurrent chemoradiotherapy for localized esophageal squamous cell carcinoma

Definitive chemoradiotherapy is the standard of care for inoperable locoregionally advanced esophageal squamous cell carcinoma (ESCC). Immune checkpoint inhibitors such as anti-PD-1/PD-L1 antibodies have led to a paradigm shift in advanced, metastatic ESCC treatment; however, the effect of incorporating checkpoint inhibitors in the definitive management of ESCC is unclear. Tislelizumab is an anti-PD-1 antibody specifically engineered to minimize FcɣR binding on macrophages to abrogate antibody-dependent phagocytosis, a mechanism of T-cell clearance and potential resistance to anti-PD-1 therapy. The RATIONALE 311 study described here (BGB-A317-311; NCT03957590) is a registrational multicenter, double-blind, placebo-controlled, randomized, Phase III clinical trial designed to evaluate the efficacy and safety of tislelizumab combined with concurrent chemoradiotherapy in patients with inoperable localized ESCC.

Nivolumab for the treatment of esophageal cancer

Introduction: Esophageal cancer (EC) is the seventh most common cancer and the sixth leading cause of cancer death worldwide. The prognosis for advanced EC patients remains poor and there are few effective therapeutic agents available. Nivolumab is a fully human IgG4 monoclonal antibody that exerts antitumor activity by inhibiting the interaction of programmed cell death protein 1 on activated lymphocytes with its ligands. Nivolumab monotherapy showed significant benefit for overall survival of patients with advanced esophageal squamous cell carcinoma (ESCC) relative to taxane as a second-line treatment. Additionally, adjuvant nivolumab monotherapy showed significant disease-free survival benefit relative to placebo for resectable EC patients with residual pathologic disease who had received neoadjuvant chemoradiotherapy followed by surgery.Areas covered: Here, we provide an overview of checkpoint blockade with nivolumab and present the available clinical data related to its use in EC.Expert opinion: Nivolumab should be the standard second-line treatment for advanced ESCC patients and possibly adjuvant treatment of choice after neoadjuvant chemoradiotherapy followed by surgery. Trials assessing efficacy of a combination of cytotoxic agents and nivolumab as first-line treatment, nivolumab-containing chemoradiotherapy, and neoadjuvant chemotherapy are ongoing. These trials should result in improved protocols for better clinical outcomes in EC.

Progress in Multimodal Treatment for Advanced Esophageal Squamous Cell Carcinoma: Results of Multi-Institutional Trials Conducted in Japan

In Japan, the therapeutic strategies adopted for esophageal carcinoma are based on the results of multi-institutional trials conducted by the Japan Esophageal Oncology Group (JEOG), a subgroup of the Japan Clinical Oncology Group (JCOG). Owing to the differences in the proportion of patients with squamous cell carcinoma among all patients with esophageal carcinoma, chemotherapeutic drugs available, and surgical procedures employed, the therapeutic strategies adopted in Asian countries, especially Japan, are often different from those in Western countries. The emphasis in respect of postoperative adjuvant therapy for patients with advanced esophageal squamous cell carcinoma (ESCC) shifted from postoperative radiotherapy in the 1980s to postoperative chemotherapy in the 1990s. In the 2000s, the optimal timing of administration of perioperative adjuvant chemotherapy returned from the postoperative adjuvant setting to the preoperative neoadjuvant setting. Recently, the JEOG commenced a three-arm randomized controlled trial of neoadjuvant therapies (cisplatin + 5-fluorouracil (CF) vs. CF + docetaxel (DCF) vs. CF + radiation therapy (41.4 Gy) (CRT)) for localized advanced ESCC, and patient recruitment has been completed. Salvage and conversion surgeries for ESCC have been developed in Japan, and the JEOG has conducted phase I/II trials to confirm the feasibility and safety of such aggressive surgeries. At present, the JEOG is conducting several trials for patients with resectable and unresectable ESCC, according to the tumor stage. Herein, we present a review of the JEOG trials conducted for advanced ESCC.

Optimal preoperative neoadjuvant therapy for resectable locally advanced esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies worldwide, especially in East Asia. ESCC accounts for more than 90% of esophageal cancer. Currently, neoadjuvant therapy in combination with surgical resection is the mainstay of treatment. However, the overall survival rate of patients with locally advanced ESCC is not satisfactory even when treated following the standard treatment guidelines. With neoadjuvant chemoradiotherapy, chemotherapy, or emerging immunotherapy, continuous exploration of efficacy in relation to ESCC is expected to improve overall survival further. Here, we review and summarize current evidence for efficacy of preoperative therapy for locally advanced ESCC.

Immuno-oncology for esophageal cancer

Esophageal cancer (EC) is the seventh most common cancer, with a poor prognosis for metastatic EC patients and limited effective drugs for treatment. Nivolumab and pembrolizumab, monoclonal antibodies that inhibit interactions of PD-1 and its ligand (PD-L1), which induce lymphocyte activation, have antitumor activity. The ATTRACTION-3 trial compared nivolumab with taxane after first-line chemotherapy and demonstrated superior overall survival (OS) for esophageal squamous cell carcinoma. The KEYNOTE-181 trial that compared pembrolizumab with chemotherapy demonstrated superior OS for EC with a PD-L1 combined positive score ≥10. Trials to evaluate efficacy of combined cytotoxic agents and immune checkpoint inhibitors (ICI) as first-line chemotherapies, ICI-containing chemoradiotherapy, and pre/postoperative chemotherapy are ongoing and might provide important data to improve clinical outcomes.

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.