Second-line pembrolizumab versus chemotherapy in Japanese patients with advanced esophageal cancer: subgroup analysis from KEYNOTE-181

Treatment-related pneumonitis after thoracic radiotherapy/chemoradiotherapy combined with anti-PD-1 monoclonal antibodies in advanced esophageal squamous cell carcinoma

PURPOSE

This study aims to evaluate the risk factors of treatment-related pneumonitis (TRP) following thoracic radiotherapy/chemoradiotherapy combined with anti-PD‑1 monoclonal antibodies (mAbs) in patients with advanced esophageal squamous cell carcinoma (ESCC).

METHODS

We retrospectively reviewed 97 patients with advanced ESCC who were treated with thoracic radiotherapy/chemoradiotherapy combined with anti-PD‑1 mAbs. Among them, 56 patients received concurrent radiotherapy with anti-PD‑1 mAbs and 41 patients received sequential radiotherapy with anti-PD‑1 mAbs. The median prescribed planning target volume (PTV) dose was 59.4 Gy (range from 50.4 to 66 Gy, 1.8-2.2 Gy/fraction). Clinical characteristics, the percentage of lung volume receiving more than 5-50 Gy in increments of 5 Gy (V5-V50, respectively) and the mean lung dose (MLD) were analyzed as potential risk factors for TRP.

RESULTS

46.4% (45/97), 20.6% (20/97), 20.6% (20/97), 4.1% (4/97), and 1.0% (1/97) of the patients developed any grade of TRP, grade 1 TRP, grade 2 TRP, grade 3 TRP, and fatal (grade 5) TRP, respectively. Anti-PD‑1 mAbs administered concurrently with radiotherapy, V5, V10, V15, V25, V30, V35, V40 and MLD were associated with the occurrence of grade 2 or higher TRP. Concurrent therapy (P = 0.010, OR = 3.990) and V5 (P = 0.001, OR = 1.126) were independent risk factors for grade 2 or higher TRP. According to the receiver operating characteristic (ROC) curve analysis, the optimal V5 threshold for predicting grade 2 or higher TRP was 55.7%.

CONCLUSION

The combination of thoracic radiotherapy/chemoradiotherapy with anti-PD‑1 mAbs displayed a tolerable pulmonary safety profile. Although the incidence of TRP was high, grade 1-2 TRP accounted for the majority. Anti-PD‑1 mAbs administered concurrently with radiotherapy and the lung V5 were significantly associated with the occurrence of grade 2 or higher TRP. Therefore, it seems safer to control V5 below 55% in clinical, especially for the high-risk populations receiving concurrent therapy.

Efficacy and safety of PD-1 Monoclonal antibodies in the treatment of esophageal squamous cell carcinoma: Systematic review and meta Regression

Background

Esophageal Squamous Cell Carcinoma (ESCC) contributes to the global burden of disease. Conventional treatments such as surgical resection and chemotherapy offer limited long-term survival rates. Recently, immunotherapies targeting PD-1 have shown promise in other cancers, but their efficacy in ESCC remains unclear.

Methods

The 31 studies eligible for this study included a total of 10,681 patients who were subjected to immunotherapy, either alone or in combination with traditional chemotherapy. A comprehensive search was conducted on September 1, 2023, across databases including CENTRAL, PubMed, MEDLINE, Web of Science, Embase, and Scopus.

Results

For OSR, results indicate a significantly improved survival at different time points (6, 12, and 24 months), with an odds ratio of 0.636 (95 % CI 0.595-0.680; Z = -13.292; p < 0.00001). In terms of PFS, PD-1 inhibitors demonstrated improvements at different time points; pooled odds ratio was 0.568 (95 % CI 0.511-0.633; Z = -10.357; p < 0.00001). Regarding ORR, the pooled analysis showed an overall odds ratio of 1.724 (95 % CI 1.554-1.913; Z = 10.289; p < 0.00001), indicating improved treatment response. DCR did not suggest a significant advantage for PD-1 inhibitors over chemotherapy, with an odds ratio of 0.904 (95 % CI 0.784-1.043; Z = -1.381; p = 0.167).

Conclusions

There is compelling evidence reinforcing the efficacy and safety of PD-1 inhibitors, as monotherapy or in combination with chemotherapy, for the treatment of ESCC. PD-1 inhibitors demonstrate a significant advantage in terms of OSR, PFS, and ORR.

Meta-Analysis of the Efficacy and Safety of Pembrolizumab in the Treatment of Advanced Gastric Cancer and Gastroesophageal Junction Cancer

INTRODUCTION

Pembrolizumab has been approved for the first-line treatment of patients with advanced gastric cancer (GC) and gastroesophageal junction (GEJ) cancer. However, the results of several clinical trials are not entirely consistent, and the dominant population of first-line immunotherapy for advanced GC/GEJ still needs to be precisely determined.

PURPOSE

The aim of this meta-analysis was to assess the efficacy and safety of pembrolizumab in the treatment of advanced GC/GEJ.

METHODS

We conducted computerized searches across multiple databases, including PubMed, Cochrane Library, Web of Science, and Embase. We established the inclusion criteria to comprise randomized clinical trials examining the efficacy of pembrolizumab in late-stage GC/GCJ cancer. We conducted a meta-analysis of outcome measures using STATA 14.0 software.

RESULTS

A total of six studies involving 1,448 cases were included in this analysis. The results of the meta-analysis indicate that, when compared to chemotherapy, patients in the pembrolizumab group experienced a significant reduction in the risk of mortality in terms of overall survival (OS) (hazard ratio [HR] = 0.72, 95% confidence interval [CI]: 0.65-0.79, p < 0.01). In terms of progression-free survival (PFS), pembrolizumab was associated with a similar PFS as compared to chemotherapy (HR = 0.88, 95% CI: 0.73-1.07, p = 0.206). Subgroup analyses based on PD-L1 expression levels indicated a significantly longer PFS with pembrolizumab in subgroups of patients with PD-L1 CPS ≥10 but not in those with PD-L1 CPS ≥1 and PD-L1 CPS ≥5. Subgroup analyses based on distinct geographical regions revealed a comparable effect of PFS in patients residing in Asia or the USA Subgroup analysis based on tumor sites consistently demonstrated a similar effect of PFS in patients with EC/GEJ tumors and GC patients.

CONCLUSION

Our findings demonstrated that pembrolizumab led to a significant extension in OS and objective response rate, along with a favorable tolerability profile compared to chemotherapy. Furthermore, the observed survival benefits were particularly pronounced in subgroup patients with a CPS of ≥10. Given the potential limitations inherent in our study, it is imperative to underscore the necessity for further large-scale RCTs to corroborate our results.

An updated review of immunotherapy in esophageal cancer: PD-L1 footprint

Esophageal cancer is considered one of the most significant challenges to public health worldwide. While various therapeutic options exist for esophageal cancer, including chemotherapy, radiotherapy, and surgery, several adverse effects of these medications have been reported. Therefore, a new generation of therapeutic lines should be applied to minimize complications. In this regard, immunotherapy is a novel approach that aims to kill tumor cells directly by targeting them. Specifically, monoclonal antibodies can target specific markers of esophageal cancer tumor cells, keeping other normal cells safe. Multiple monoclonal antibodies optimized for esophageal cancer, such as pembrolizumab, ramucirumab, trastuzumab, nivolumab, and ipilimumab, are available. On the other hand, esophageal cancer tumor cells express a specific inhibitory ligand and its receptor called programmed cell death, which can suppress T cell immune responses. This receptor provides an inhibitory signal, causing the highest expression of the PD-L1 ligand on tumor cells. The outcomes of this interaction lead to the suppression of the activation and function of T lymphocytes. Therefore, immunotherapy for esophageal cancer targeting the PD-1/PD-L1 pathway has shown a remarkable correlation with cancer care. This study presents a comprehensive review of the latest findings related to immunotherapy in esophageal cancer.

Development of an Interpretable Deep Learning Model for Pathological Tumor Response Assessment After Neoadjuvant Therapy

BACKGROUND

Neoadjuvant therapy followed by surgery has become the standard of care for locally advanced esophageal squamous cell carcinoma (ESCC) and accurate pathological response assessment is critical to assess the therapeutic efficacy. However, it can be laborious and inconsistency between different observers may occur. Hence, we aim to develop an interpretable deep-learning model for efficient pathological response assessment following neoadjuvant therapy in ESCC.

METHODS

This retrospective study analyzed 337 ESCC resection specimens from 2020-2021 at the Pudong-Branch (Cohort 1) and 114 from 2021-2022 at the Puxi-Branch (External Cohort 2) of Fudan University Shanghai Cancer Center. Whole slide images (WSIs) from these two cohorts were generated using different scanning machines to test the ability of the model in handling color variations. Four pathologists independently assessed the pathological response. The senior pathologists annotated tumor beds and residual tumor percentages on WSIs to determine consensus labels. Furthermore, 1850 image patches were randomly extracted from Cohort 1 WSIs and binarily classified for tumor viability. A deep-learning model employing knowledge distillation was developed to automatically classify positive patches for each WSI and estimate the viable residual tumor percentages. Spatial heatmaps were output for model explanations and visualizations.

RESULTS

The approach achieved high concordance with pathologist consensus, with an R^2 of 0.8437, a RAcc_0.1 of 0.7586, a RAcc_0.3 of 0.9885, which were comparable to two senior pathologists (R^2 of 0.9202/0.9619, RAcc_0.1 of 8506/0.9425, RAcc_0.3 of 1.000/1.000) and surpassing two junior pathologists (R^2 of 0.5592/0.5474, RAcc_0.1 of 0.5287/0.5287, RAcc_0.3 of 0.9080/0.9310). Visualizations enabled the localization of residual viable tumor to augment microscopic assessment.

CONCLUSION

This work illustrates deep learning's potential for assisting pathological response assessment. Spatial heatmaps and patch examples provide intuitive explanations of model predictions, engendering clinical trust and adoption (Code and data will be available at https://github.com/WinnieLaugh/ESCC_Percentage once the paper has been conditionally accepted). Integrating interpretable computational pathology could help enhance the efficiency and consistency of tumor response assessment and empower precise oncology treatment decisions.

Second-line tislelizumab versus chemotherapy in Japanese patients with advanced or metastatic esophageal squamous cell carcinoma: subgroup analysis from RATIONALE-302

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) has a poor prognosis, with limited second-line systemic therapy options, and represents an increasing disease burden in Japan. In the phase 3 RATIONALE-302 study, the anti-programmed cell death protein 1 antibody, tislelizumab, significantly improved overall survival (OS) versus chemotherapy as second-line treatment for advanced/metastatic ESCC. Here, we report the Japanese patient subgroup results.

METHODS

Patients with advanced/metastatic ESCC, with disease progression during/after first-line systemic therapy were randomized 1:1 to open-label tislelizumab 200 mg every 3 weeks or investigator's choice of chemotherapy (paclitaxel/docetaxel). Efficacy and safety were assessed in all randomized Japanese patients.

RESULTS

The Japanese subgroup comprised 50 patients (n = 25 per arm). Tislelizumab improved OS versus chemotherapy (median: 9.8 vs. 7.6 months; HR 0.59; 95% CI 0.31, 1.12). Among patients with programmed death-ligand 1 score ≥ 10%, median OS was 12.5 months with tislelizumab (n = 10) versus 2.9 months with chemotherapy (n = 6) (HR 0.31; 95% CI 0.09, 1.03). Tislelizumab improved progression-free survival versus chemotherapy (median: 3.6 vs. 1.7 months, respectively; HR 0.50; 95% CI 0.27, 0.95). Objective response rate was greater with tislelizumab (32.0%) versus chemotherapy (20.0%), and responses were more durable (median duration of response: 8.8 vs. 2.6 months, respectively). Fewer patients experienced ≥ grade 3 treatment-related adverse events with tislelizumab (24.0%) versus chemotherapy (47.8%). Tislelizumab demonstrated an improvement in health-related quality of life versus chemotherapy.

CONCLUSIONS

As second-line therapy for advanced/metastatic ESCC, tislelizumab improved OS versus chemotherapy, with a favorable safety profile, in the Japanese patient subgroup, consistent with the overall population.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov: NCT03430843.

First-line nivolumab plus ipilimumab or chemotherapy versus chemotherapy alone in advanced esophageal squamous cell carcinoma: a Japanese subgroup analysis of open-label, phase 3 trial (CheckMate 648/ONO-4538-50)

BACKGROUND

Programmed cell death 1 (PD-1)-based treatments are approved for several cancers. CheckMate 648, a global, phase 3 trial, showed that first-line nivolumab (anti-PD-1 antibody) plus ipilimumab (NIVO + IPI) or nivolumab plus chemotherapy (NIVO + Chemo) significantly increased survival in advanced esophageal squamous cell carcinoma (ESCC) without new safety signals versus chemotherapy alone (Chemo).

METHODS

We evaluated the Japanese subpopulation of CheckMate 648 (n = 394/970), randomized to receive first-line NIVO + IPI, NIVO + Chemo, or Chemo. Efficacy endpoints included overall survival (OS) and progression-free survival assessed by blinded independent central review in Japanese patients with tumor-cell programmed death-ligand 1 (PD-L1) expression ≥ 1% and in all randomized Japanese patients.

RESULTS

In the Japanese population, 131, 126, and 137 patients were treated with NIVO + IPI, NIVO + Chemo, and Chemo, and 66, 62, and 65 patients had tumor-cell PD-L1 ≥ 1%, respectively. In patients with tumor-cell PD-L1 ≥ 1%, median OS was numerically longer with NIVO + IPI (20.2 months; hazard ratio [95% CI], 0.46 [0.30-0.71]) and NIVO + Chemo (17.3 months; 0.53 [0.35-0.82]) versus Chemo (9.0 months). In all randomized patients, median OS was numerically longer with NIVO + IPI (17.6 months; 0.68 [0.51-0.92]) and NIVO + Chemo (15.5 months; 0.73 [0.54-0.99]) versus Chemo (11.0 months). Grade 3-4 treatment-related adverse events were reported in 37%, 49%, and 36% of all patients in the NIVO + IPI, NIVO + Chemo, and Chemo arms, respectively.

CONCLUSION

Survival benefits with acceptable tolerability observed for NIVO + IPI and NIVO + Chemo treatments strongly support their use as a new standard first-line treatment in Japanese patients with advanced ESCC.

CLINICALTRIALS

GOV ID

NCT03143153.

Cold atmospheric plasma: Novel opportunities for tumor microenvironment targeting

With mounting preclinical and clinical evidences on the prominent roles of the tumor microenvironment (TME) played during carcinogenesis, the TME has been recognized and used as an important onco-therapeutic target during the past decade. Delineating our current knowledge on TME components and their functionalities can help us recognize novel onco-therapeutic opportunities and establish treatment modalities towards desirable anti-cancer outcome. By identifying and focusing on primary cellular components in the TME, that is, tumor-infiltrating lymphocytes, tumor-associated macrophages, cancer-associated fibroblasts and mesenchymal stem cells, we decomposed their primary functionalities during carcinogenesis, categorized current therapeutic approaches utilizing traits of these components, and forecasted possible benefits that cold atmospheric plasma, a redox modulating tool with selectivity against cancer cells, may convey by targeting the TME. Our insights may open a novel therapeutic avenue for cancer control taking advantages of redox homeostasis and immunostasis.

Predictive value of PD-L1 expression in response to immune checkpoint inhibitors for esophageal cancer treatment: A systematic review and meta-analysis

Background

Programmed death-ligand-1 (PD-L1) molecule is a well-known predictive biomarker for the efficacy of immune checkpoint inhibitors (ICIs) in several cancers. Present systematic review and meta-analysis aimed at investigating the role of PD-L1 in predicting the effectiveness of programmed death-1 (PD-1)/PD-L1 inhibitors in patients suffering from esophageal cancer.

Methods

We searched PubMed, Scopus, Web of Science, and EMBASE databases as of March 25, 2022, for retrieving the potential relevant randomized controlled trials (RCTs). The pooled hazard ratios (HR) and the corresponding 95% confidence intervals (95%CIs) were calculated for the outcomes of overall survival (OS) and progression-free survival (PFS). The primary objective was to investigate the association between PD-1/PD-L1 inhibitors vs. control agents and treatment efficacy in terms of OS in patients with esophageal tumor expressing different values of PD-L1 based on combined-positive score (CPS) and tumor proportion score (TPS). The secondary outcome was the pooled risk of PFS.

Results

Eleven studies with a total of 5,418 participants were included. While there was no difference in the OS of CPS<1 patients in the intervention and the control group, patients bearing esophageal tumors with a CPS≥1 (HR 0.65, 0.56-0.74) treated by ICIs showed a significant improvement in OS relative to the control agents. Accordingly, patients with CPS<5 (HR 0.75, 0.58-0.98), CPS≥5 (HR 0.64, 0.53-0.77), CPS<10 (HR 0.86, 0.76-0.98), and CPS≥10 (HR 0.65, 0.56-0.75) had improved OS; however, a significant longer OS was observed in cases who expressed higher values of CPS=10 (p=0.018). In terms of TPS, a significant greater benefit in prolonging the OS came from TPS≥1% PD-L1 expressing tumors in comparison to TPS<1% tumors, suggesting this cut-off as another predictor of PD-1/PD-L1 inhibitors efficacy. Notably, in the subgroup analysis when the cut-off value of CPS=10 or TPS=1% was selected, Nivolumab was the best ICI that improved the survival of PD-L1 positive patients. In patients with negative PD-L1 expression, Toripalimib is the only ICI which could prolong the OS of patients with the cut-off value of CPS=10.

Conclusion

Among patients suffering from esophageal cancer, PD-L1 CPS=10 and TPS=1% expression thresholds seem to be predictive of a lower rate of mortality when PD-1/PD-L1 inhibitors are administrated; however, further large-scale trials are required for confirming the findings of the present study.