Progress in second-line antibody therapies for advanced esophageal squamous cell carcinoma.

INTRODUCTION: The prognosis of advanced esophageal squamous cell carcinoma (ESCC) is poor. Although cytotoxic drugs have been widely used in advanced ESCC, several antibody agents have recently been reported to be effective. AREAS COVERED: Nivolumab and pembrolizumab are anti-PD-1 antibodies that improve immunosuppression by binding to programmed death-1 (PD-1), leading to an antitumor effect. Randomized phase III trials have found these immune checkpoint inhibitors (ICIs) to be effective as second-line treatment. ATTRACTION-3, which compared nivolumab monotherapy with taxane monotherapy in patients with previously treated advanced ESCC, reported prolonged overall survival in the nivolumab group. KEYNOTE-181 found that overall survival was longer in patients with PD-L1-positive ESCC who received second-line treatment with pembrolizumab than in those who received chemotherapy. Sym004 and amivantamab are antibodies that target the epidermal growth factor receptor and have demonstrated efficacy in the treatment of other tumors in recent phase I studies. Furthermore, clinical trials on antibody-drug conjugates such as enfortumab vedotin and DS-7300 for solid tumors are currently ongoing. EXPERT OPINION: The standard first-line treatments for patients with advanced ESCC contain ICIs. Therefore, drugs with different mechanisms of action that can overcome resistance to ICIs are needed as second-line or later-line treatments to improve clinical outcomes in these patients.

BRAF V600E-mutant colorectal cancer with CNS metastases treated successfully with encorafenib, binimetinib and cetuximab.

This report describes a case of BRAF V600E-mutated colorectal cancer with CNS metastases in which treatment with encorafenib, binimetinib and cetuximab was effective. There is limited information on the ability of encorafenib, binimetinib and cetuximab to enter the CNS.The patient was a 53-year-old man was diagnosed with ascending colon cancer (cT3N3M1c stage IVc). BRAF V600E mutation was confirmed. FOLFOX was started, but CNS metastases soon appeared. Encorafenib, binimetinib and cetuximab were administered and had a favorable effect on the CNS lesions. The patient initially responded well, but his disease progressed 2 months later. Further research is needed to improve management strategies for BRAF V600E-mutated colorectal cancer with CNS metastases.

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Doublet chemotherapy, triplet chemotherapy, or doublet chemotherapy combined with radiotherapy as neoadjuvant treatment for locally advanced oesophageal cancer (JCOG1109 NExT): a randomised, controlled, open-label, phase 3 trial.

BACKGROUND: Neoadjuvant therapy is the standard treatment for patients with locally advanced oesophageal squamous cell carcinoma (OSCC). However, the prognosis remains poor and more intensive neoadjuvant treatment might be needed to improve patient outcomes. We therefore aimed to compare the efficacy and safety of neoadjuvant doublet chemotherapy, triplet chemotherapy, and doublet chemotherapy plus radiotherapy in patients with previously untreated locally advanced OSCC. METHODS: In this randomised, open-label, phase 3 trial, patients aged 20-75 years with previously untreated locally advanced OSCC and an Eastern Cooperative Oncology Group performance status of 0 or 1 were recruited from 44 centres across Japan. Patients were randomly assigned (1:1:1) centrally via a web-based system to receive neoadjuvant doublet chemotherapy (two courses of fluorouracil [800 mg/m2 per day intravenously on days 1-5] and cisplatin [80 mg/m2 per day on day 1] separated by an interval of 3 weeks [NeoCF]), triplet chemotherapy (three courses of fluorouracil [750 mg/m2 per day on days 1-5], cisplatin [70 mg/m2 per day on day 1], and docetaxel [70 mg/m2 per day on day 1] repeated every 3 weeks [NeoCF+D]), or doublet chemotherapy (two courses of fluorouracil [1000 mg/m2 per day on days 1-4] and cisplatin [75 mg/m2 per day on day 1] separated by an interval of 4 weeks) plus 41·4 Gy radiotherapy [NeoCF+RT]) followed by oesophagectomy with regional lymph node dissection. Randomisation was stratified by T stage and institution. Participants, investigators, and those assessing outcomes were not masked to group assignment. The primary endpoint was overall survival, analysed by intention to treat. Analysis of safety included all patients who received at least one course of chemotherapy, and analysis of surgical complications included those who also underwent surgery. This study is registered with the Japan Registry of Clinical Trials, jRCTs031180202, and the trial is complete. FINDINGS: A total of 601 patients (529 male individuals and 72 female individuals) were randomly assigned between Dec 5, 2012, and July 20, 2018, with 199 patients in the NeoCF group, 202 patients in the NeoCF+D group, and 200 patients in the NeoCF+RT group. Compared with the NeoCF group, during a median follow-up period of 50·7 months (IQR 23·8-70·7), the 3-year overall survival rate was significantly higher in the NeoCF+D group (72·1% [95% CI 65·4-77·8] vs 62·6% [55·5-68·9]; hazard ratio [HR] 0·68, 95% CI 0·50-0·92; p=0·006) but not in the NeoCF+RT group (68·3% [61·3-74·3]; HR 0·84, 0·63-1·12; p=0·12). Grade 3 or higher febrile neutropenia occurred in two (1%) of 193 patients in the NeoCF group, 32 (16%) of 196 patients in the NeoCF+D group, and nine (5%) of 191 patients in the NeoCF+RT group. Treatment-related adverse events leading to termination of neoadjuvant therapy were more common in the NeoCF+D group (18 [9%] of 202 participants) than in the NeoCF+RT group (12 [6%] of 200) and NeoCF group (eight [4%] of 199). There were three (2%) treatment-related deaths during neoadjuvant therapy in the NeoCF group, four (2%) deaths in the NeoCF+D group, and two (1%) deaths in the NeoCF+RT group. Grade 2 or higher postoperative pneumonia, anastomotic leak, and recurrent laryngeal nerve paralysis were reported in 19 (10%), 19 (10%), and 28 (15%) of 185 patients, respectively, in the NeoCF group; 18 (10%), 16 (9%), and 19 (10%) of 183 patients, respectively, in the NeoCF+D group; and 23 (13%), 23 (13%), and 17 (10%) of 178 patients, respectively, in the NeoCF+RT group. The in-hospital deaths following surgery included three deaths in the NeoCF group, two deaths in the NeoCF+D group, and one in the NeoCF+RT group. INTERPRETATION: Neoadjuvant triplet chemotherapy followed by oesophagectomy resulted in a statistically significant overall survival benefit compared with doublet chemotherapy and might be the new standard of care for locally advanced OSCC who are in good condition in Japan. Neoadjuvant doublet chemotherapy plus radiotherapy did not show significant improvement of survival compared with doublet chemotherapy. FUNDING: Japan Agency for Medical Research and Development and National Cancer Center Research and Development Fund.

Time Course of Left Ventricular Strain Assessment via Cardiovascular Magnetic Resonance Myocardial Feature Tracking in Takotsubo Syndrome.

Background: Although takotsubo syndrome (TTS) is characterized by transient systolic dysfunction of the left ventricle (LV), the time course and mechanism of LV function recovery remain elusive. The aim of this study is to evaluate cardiac functional recovery in TTS via serial cardiac magnetic resonance feature tracking (CMR-FT). Methods: In this Japanese multicenter registry, patients with newly diagnosed TTS were prospectively enrolled. In patients who underwent serial cardiovascular magnetic resonance (CMR) imaging at 1 month and 1 year after the onset, CMR-FT was performed to determine the global circumferential strain (GCS), global radial strain (GRS) and global longitudinal strain (GLS). We compared LV ejection fraction, GCS, GRS and GLS at 1 month and 1 year after the onset of TTS. Results: Eighteen patients underwent CMR imaging in one month and one year after the onset in the present study. LV ejection fraction had already normalized at 1 month after the onset, with no significant difference between 1 month and 1 year (55.8 ± 9.2% vs. 58.9 ± 7.3%, p = 0.09). CMR-FT demonstrated significant improvement in GCS from 1 month to 1 year (-16.7 ± 3.4% vs. -18.5 ± 3.2%, p < 0.01), while there was no significant difference in GRS and GLS between 1 month and year (GRS: 59.6 ± 24.2% vs. 59.4 ± 17.3%, p = 0.95, GLS: -12.8 ± 5.9% vs. -13.8 ± 4.9%, p = 0.42). Conclusions: Serial CMR-FT analysis revealed delayed improvement of GCS compared to GRS and GLS despite of rapid recovery of LV ejection fraction. CMR-FT can detect subtle impairment of LV systolic function during the recovery process in patients with TTS.

Development of perioperative immune checkpoint inhibitor therapy for locally advanced esophageal squamous cell carcinoma.

The standard preoperative treatment for resectable locally advanced esophageal squamous cell carcinoma (ESCC) is chemoradiotherapy in western countries (based on the CROSS trial) and triplet chemotherapy in Japan (based on the JCOG1109 trial). Postoperative nivolumab has recently been shown to improve disease-free survival in resectable locally advanced esophageal cancer after preoperative chemoradiotherapy in patients who had residual pathological disease, based on the CheckMate 577 trial. Furthermore, preoperative immune checkpoint inhibitor-containing treatments have also been developed. The JCOG1804E trial is presently evaluating the safety and efficacy of preoperative nivolumab-containing chemotherapy for resectable locally advanced ESCC. This review discusses the treatment of resectable locally advanced ESCC and future perspectives on perioperative immune checkpoint inhibitor-containing treatments.

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Impact of immune checkpoint inhibitors on survival outcomes in advanced gastric cancer in Japan: A real-world analysis.

BACKGROUND: Nivolumab was approved for the treatment of advanced gastric cancer in 2017 in Japan. The aim of this study was to assess the impact of nivolumab in a real-world clinical setting. METHODS: This single-institutional retrospective study included patients with advanced gastric or esophagogastric junction adenocarcinoma and a history of first-line chemotherapy with platinum-based doublet or triplet regimens between 2010 and 2020. To assess the impact of nivolumab on survival, the patients were divided based on the year of nivolumab approval into a pre-2017 (2010-2016) group and a post-2017 (2017-2020) group. RESULTS: From a total of 1918 patients, 1093 were excluded. There were 533 patients in the pre-2017 group and 292 in the post-2017 group. Immune checkpoint inhibitors were used significantly more often in the post-2017 group than in the pre-2017 group (8.6% vs. 47.9%). Median overall survival was significantly longer in the post-2017 group (16.9 vs. 13.9 months; hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.63-0.90; p < 0.01). The proportion of patients transitioning to third-line treatment was higher in the post-2017 group than in the pre-2017 group (56.3% vs. 43.8%, p < 0.01). Median survival outcomes following progression on second-line treatment were significantly longer in the post-2017 group (4.3 vs. 3.2 months; HR 0.70, 95% CI 0.57-0.86; p < 0.01). CONCLUSION: The proportion of patients transitioning to third-line treatment and survival outcomes following progression on second-line treatment have improved since the approval of nivolumab. This drug might help to prolong overall survival in real-world practice.

Health-related quality-of-life analysis from KEYNOTE-590: pembrolizumab plus chemotherapy versus chemotherapy for advanced esophageal cancer.

BACKGROUND: In the KEYNOTE-590 study, first-line pembrolizumab plus chemotherapy provided statistically significant improvement in overall survival, progression-free survival, and objective response rate compared with chemotherapy, with a manageable safety profile in patients with advanced esophageal cancer. Prespecified health-related quality-of-life (HRQoL) outcomes are reported. MATERIALS AND METHODS: Change from baseline to week 18 in the EORTC Quality of Life Questionnaire Core 30 (QLQ-C30) global health status/QoL (GHS/QoL) and QLQ-Esophageal cancer module (OES18) dysphagia, pain, and reflux scales were evaluated. RESULTS: The HRQoL analysis included 730 patients who received treatment and completed ≥1 HRQoL assessment. Least squares mean (LSM) change from baseline to week 18 was similar between treatment groups for QLQ-C30 GHS/QoL and physical functioning and QLQ-OES18 reflux scales. The QLQ-OES18 dysphagia (LSM difference, -5.54; 95% CI, -10.93 to -0.16) and pain (LSM difference, -2.94; 95% CI, -5.86 to -0.02) scales favored pembrolizumab plus chemotherapy over placebo plus chemotherapy. Median time to confirmed deterioration (TTD) was similar between treatment groups for QLQ-C30 GHS/QoL and physical functioning and QLQ-OES18 dysphagia and reflux scales. Compared with chemotherapy, pembrolizumab plus chemotherapy prolonged median TTD, as seen on the QLQ-OES18 pain scale (HR, 0.69; 95% CI, 0.51 to 0.95). CONCLUSION: The use of pembrolizumab plus chemotherapy maintained HRQoL at week 18 relative to baseline and was comparable with placebo plus chemotherapy. These HRQoL results together with published reports of efficacy, support the use of pembrolizumab plus chemotherapy as first-line therapy for advanced/metastatic esophageal cancer. CLINICALTRIALS.GOV ID: NCT03189719.

LEAP-014: first-line lenvatinib + pembrolizumab + chemotherapy in advanced/metastatic esophageal squamous cell carcinoma.

Treatment options for patients with advanced or metastatic esophageal squamous cell carcinoma (ESCC) are improving. Current guidelines recommend first-line pembrolizumab plus chemotherapy for patients with unresectable or metastatic ESCC, which has led to improvements in survival outcomes. Antiangiogenic therapy combined with immune checkpoint inhibitors can act synergistically to convert the immunosuppressive tumor microenvironment to an immune supportive microenvironment, thus enhancing antitumor immune responses. In preclinical models, the antiangiogenic agent lenvatinib combined with an anti-PD-1 agent showed synergistic antitumor activity. We describe the design and rationale for the randomized, open-label, phase III LEAP-014 study of lenvatinib in combination with pembrolizumab plus chemotherapy in patients with advanced or metastatic ESCC. Overall survival and progression-free survival are the dual primary end points.Clinical Trial Registration: NCT04949256 (ClinicalTrials.gov).

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Nivolumab plus chemotherapy or ipilimumab versus chemotherapy in patients with advanced esophageal squamous cell carcinoma (CheckMate 648): 29-month follow-up from a randomized, open-label, phase III trial.

BACKGROUND: First-line nivolumab plus chemotherapy and nivolumab plus ipilimumab both demonstrated significant overall survival (OS) benefit versus chemotherapy in previously untreated patients with advanced esophageal squamous cell carcinoma (ESCC) in the CheckMate 648 trial, leading to approvals of both nivolumab-containing regimens in many countries. We report longer-term follow-up data. METHODS: This open-label, phase III trial (NCT03143153) enrolled adults with previously untreated, unresectable, advanced, recurrent, or metastatic ESCC. Patients were randomized 1:1:1 to nivolumab plus chemotherapy, nivolumab plus ipilimumab, or chemotherapy. Primary endpoints were OS and progression-free survival (PFS) by blinded independent central review. Hierarchical testing was performed first in patients with tumor cell programmed death ligand 1 (PD-L1) expression of ≥1% and then in the overall population. RESULTS: A total of 970 patients were randomly assigned. After 29 months of minimum follow-up, nivolumab plus chemotherapy continued to demonstrate improvement in OS versus chemotherapy (hazard ratio [HR] = 0.59 [95% CI: 0.46-0.76]) in patients with tumor cell PD-L1 expression of ≥1% and in the overall population (HR = 0.78 [95% CI: 0.65-0.93]) and with nivolumab plus ipilimumab versus chemotherapy (HR = 0.62 [95% CI: 0.48-0.80]) in patients with tumor cell PD-L1 expression of ≥1% and in the overall population (HR = 0.77 [95% CI: 0.65-0.92]). In patients with tumor cell PD-L1 expression of ≥1%, nivolumab plus chemotherapy demonstrated PFS benefit versus chemotherapy (HR = 0.67 [95% CI: 0.51-0.89]); PFS benefit was not observed with nivolumab plus ipilimumab versus chemotherapy (HR = 1.04 [95% CI: 0.79-1.36]). Among all treated patients (n = 936), Grade 3-4 treatment-related adverse events were reported in 151 (49%, nivolumab plus chemotherapy), 105 (32%, nivolumab plus ipilimumab), and 110 (36%, chemotherapy) patients. CONCLUSIONS: Nivolumab plus chemotherapy and nivolumab plus ipilimumab continued to demonstrate clinically meaningful OS benefit versus chemotherapy with no new safety signals identified with longer follow-up, further supporting use as first-line standard treatment options for patients with advanced ESCC.

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.

Myasthenic Crisis and Concomitant Takotsubo Syndrome Complicated by Shock: A Case Report.

A man in his 80s with myasthenia gravis (MG) developed dysmobility and chest discomfort. An electrocardiogram revealed ST-segment elevation, and coronary angiography revealed Takotsubo syndrome (TTS). He experienced myasthenic crisis that required ventilation and shock that was refractory to vasopressors and required intra-aortic balloon pump (IABP) insertion. He was managed conservatively without MG-specific treatment until his hemodynamics improved. On hospital day 6, he was weaned from IABP. MG is a high-risk condition for TTS, and TTS with MC is associated with high mortality. We successfully managed this case of TTS with MC with intubation and IABP, without MG-specific treatment.

Tislelizumab plus chemotherapy versus placebo plus chemotherapy as first line treatment for advanced gastric or gastro-oesophageal junction adenocarcinoma: RATIONALE-305 randomised, double blind, phase 3 trial.

OBJECTIVE: To evaluate the efficacy and safety of tislelizumab added to chemotherapy as first line (primary) treatment for advanced gastric or gastro-oesophageal junction adenocarcinoma compared with placebo plus chemotherapy. DESIGN: Randomised, double blind, placebo controlled, phase 3 study. SETTING: 146 medical centres across Asia, Europe, and North America, between 13 December 2018 and 28 February 2023. PARTICIPANTS: 1657 patients aged ≥18 years with human epidermal growth factor receptor 2 negative locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma, regardless of programmed death-ligand 1 (PD-L1) expression status, who had not received systemic anticancer therapy for advanced disease. INTERVENTIONS: Patients were randomly (1:1) assigned to receive either tislelizumab 200 mg or placebo intravenously every three weeks in combination with chemotherapy (investigator's choice of oxaliplatin and capecitabine, or cisplatin and 5-fluorouracil) and stratified by region, PD-L1 expression, presence or absence of peritoneal metastases, and investigator's choice of chemotherapy. Treatment continued until disease progression or unacceptable toxicity. MAIN OUTCOME MEASURES: The primary endpoint was overall survival, both in patients with a PD-L1 tumour area positivity (TAP) score of ≥5% and in all randomised patients. Safety was assessed in all those who received at least one dose of study treatment. RESULTS: Of 1657 patients screened between 13 December 2018 and 9 February 2021, 660 were ineligible due to not meeting the eligibility criteria, withdrawal of consent, adverse events, or other reasons. Overall, 997 were randomly assigned to receive tislelizumab plus chemotherapy (n=501) or placebo plus chemotherapy (n=496). Tislelizumab plus chemotherapy showed statistically significant improvements in overall survival versus placebo plus chemotherapy in patients with a PD-L1 TAP score of ≥5% (median 17.2 months v 12.6 months; hazard ratio 0.74 (95% confidence interval 0.59 to 0.94); P=0.006 (interim analysis)) and in all randomised patients (median 15.0 months v 12.9 months; hazard ratio 0.80 (0.70 to 0.92); P=0.001 (final analysis)). Grade 3 or worse treatment related adverse events were observed in 54% (268/498) of patients in the tislelizumab plus chemotherapy arm versus 50% (246/494) in the placebo plus chemotherapy arm. CONCLUSIONS: Tislelizumab added to chemotherapy as primary treatment for advanced or metastatic gastric or gastro-oesophageal junction adenocarcinoma provided superior overall survival with a manageable safety profile versus placebo plus chemotherapy in patients with a PD-L1 TAP score of ≥5%, and in all randomised patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT03777657.

First-line pembrolizumab plus chemotherapy for advanced/metastatic esophageal cancer: 1-year extended follow-up in the Japanese subgroup of the phase 3 KEYNOTE-590 study.

BACKGROUND: First-line pembrolizumab plus chemotherapy (pembrolizumab-chemotherapy) demonstrated improved efficacy and a manageable safety profile versus placebo plus chemotherapy (placebo-chemotherapy) in the subgroup analysis of Japanese patients with advanced/metastatic esophageal cancer in KEYNOTE-590 at a median follow-up of 24.4 months. Longer-term data from the Japanese subgroup analysis of KEYNOTE-590 are reported. METHODS: Patients were randomly assigned 1:1 to pembrolizumab 200 mg or placebo every 3 weeks for ≤ 35 cycles plus chemotherapy (cisplatin 80 mg/m2 and 5-fluorouracil 800 mg/m2/day). Endpoints included overall survival (OS) and progression-free survival (PFS; investigator-assessed per RECIST v1.1; dual primary) and safety (secondary). Early tumor shrinkage (ETS) and depth of response (DpR) were assessed post hoc. RESULTS: Overall, 141 patients were enrolled in Japan. As of July 9, 2021, median follow-up was 36.6 months (range, 29.8-45.7). Pembrolizumab-chemotherapy showed a trend toward favorable OS (hazard ratio [HR], 0.70; 95% confidence interval [CI] 0.47-1.03) and PFS (0.57; 0.39-0.83) versus placebo-chemotherapy. In the pembrolizumab-chemotherapy group, patients with ETS ≥ 20% (55/74; 74.3%) versus < 20% (19/74; 25.7%) had favorable OS (HR, 0.23; 95% CI 0.12-0.42) and PFS (0.24; 0.13-0.43). Patients with DpR ≥ 60% (31/74; 41.9%) versus < 60% (43/74; 58.1%) had favorable OS (HR, 0.37; 95% CI 0.20-0.68) and PFS (0.24; 0.13-0.43). Grade 3-5 treatment-related adverse events occurred in 55/74 patients (74.3%) with pembrolizumab-chemotherapy and 41/67 patients (61.2%) with placebo-chemotherapy. CONCLUSIONS: With longer-term follow-up of Japanese patients with advanced/metastatic esophageal cancer, efficacy continued to favor pembrolizumab-chemotherapy compared with placebo-chemotherapy, with no new safety signals observed. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT03189719.

Pembrolizumab for recurrent locally advanced or metastatic squamous cell carcinoma of the esophagus: a drug safety evaluation.

INTRODUCTION: The prognosis of advanced esophageal squamous cell carcinoma (ESCC) remains poor and few effective drugs are available. Cisplatin plus 5-FU (CF) has been the standard first-line treatment for advanced ESCC. However, in the KEYNOTE-181 trial, the clinical outcomes were better in patients with programmed death ligand 1 (PD-L1)-positive advanced ESCC who received pembrolizumab, an immune checkpoint inhibitor (ICI), than in those who received cytotoxic agents as second-line treatment. Moreover, the KEYNOTE-590 trial demonstrated the superiority of pembrolizumab plus CF over CF alone in terms of overall survival. Based on the results of KEYNOTE-590, pembrolizumab plus CF has become one of the standard treatments for advanced ESCC. However, the safety profile of ICI-containing therapy is different from that of conventional cytotoxic agents. AREAS COVERED: Safety of pembrolizumab-containing therapies in patients with advanced ESCC. EXPERT OPINION: Pembrolizumab-containing therapies are tolerable as first- and second-line treatments in patients with advanced ESCC. Although infrequent, immune-related adverse events may occur in patients on pembrolizumab-containing therapies. These events are potentially fatal and require treatment with steroids or immunosuppressive drugs. Regular physical and laboratory examinations, including measurement of hormone levels, are needed during and after pembrolizumab-containing therapies in clinical practice.

CRP and soluble CTLA4 are determinants of anti-PD1 resistance in gastrointestinal cancer.

Targeting immune inhibitory checkpoint (IC) pathways have attracted great attention as a promising strategy for treating gastrointestinal (GI) cancer. However, the therapeutic efficacy is low in most cases, and little progress has been made in establishing biomarkers that predict the possible responses, and combination regimens that enhance the therapeutic efficacy. As a predictive biomarker, soluble forms of IC molecules have been recently highlighted. However, little is known about which IC molecules is most critically associated with the treatment resistance, and also about the biological and immunological roles of the IC molecules in GI cancer. In this study, we analyzed sera obtained from advanced gastric cancer patients before and one month after treatment with anti-PD1 nivolumab for soluble IC molecules by ELISA. We found that decrease of soluble CTLA4 (sCTLA4) at posttreatment were significantly associated with a better prognosis, and combination with low level of CRP at posttreatment more clearly defined anti-PD1 responders with long-term survival. Indeed, in the in vitro setting, CRP stimulation upregulated CTLA4 expression in tumor cells followed by generation of sCTLA4 that suppressed CTL induction, and simultaneously conferred high self-renewal and invasive abilities on the tumor cells accompanied by increase of EMT-related gene expressions. In the in vivo setting, CRP injection elevated sCTLA4 level in sera of mouse tumor metastasis models, leading to failure of anti-PD1 therapy. However, treatment with anti-CTLA4 mAb or a PPARγ agonist that can reduce in vivo CRP successfully elicited anti-tumor efficacy in the anti-PD1 resistant models. These suggest that targeting CRP and sCTLA4 may be a promising strategy for improving clinical outcomes in the treatments, including anti-PD1 therapy, of GI cancer.