Tumor Remission and Tumor-Infiltrating Lymphocytes During Chemoradiation Therapy: Predictive and Prognostic Markers in Locally Advanced Esophageal Squamous Cell Carcinoma

CT radiomics to predict pathologic complete response after neoadjuvant immunotherapy plus chemoradiotherapy in locally advanced esophageal squamous cell carcinoma

OBJECTIVE

To develop and validate a CT-based radiomics model to predict pathologic complete response (pCR) after neoadjuvant immunotherapy plus chemoradiotherapy (NICRT) in locally advanced esophageal squamous cell carcinoma (ESCC).

METHODS

A total of 105 patients with locally advanced ESCC receiving NICRT from February 2019 to December 2023 were enrolled. Patients were randomly divided into the training cohort and the test cohort at a 3:1 ratio. Enhanced CT scans were obtained before NICRT treatment. The 2D and 3D regions of interest were segmented, and features were extracted, followed by feature selection. Six algorithms were applied to construct the radiomics and clinical models. These models were evaluated by area under curve (AUC), accuracy, sensitivity, and specificity, and their respective optimal algorithms were further compared.

RESULTS

Forty-eight patients (45.75%) achieved pCR after NICRT. The AUC values of three algorithms in 2D radiomics models were higher than those in the 3D radiomics model and clinical model. Among these, the 2D radiomics model based on eXtreme Gradient Boosting (XGBoost) exhibited the best performance, with an AUC of 0.89 (95% CI, 0.81-0.97), accuracy of 0.85, sensitivity of 0.86, and specificity of 0.84 in the training cohort, and an AUC of 0.80 (95% CI, 0.64-0.97), accuracy of 0.77, sensitivity of 0.84, and specificity of 0.69 in the test cohort. Calibration curves also showed good agreement between predicted and actual response, and the decision curve analysis further confirmed its clinical applicability.

CONCLUSION

The 2D radiomics model can effectively predict pCR to NICRT in locally advanced ESCC.

KEY POINTS

Question Can CT-based radiomics predict pathologic complete response (pCR) after neoadjuvant immunotherapy plus chemoradiotherapy (NICRT) in locally advanced esophageal squamous cell carcinoma (ESCC)? Findings The model based on eXtreme Gradient Boosting (XGBoost) performed best, with an AUC of 0.89 in the training and 0.80 in the test cohort. Clinical relevance This CT-based radiomics model exhibits promising performance for predicting pCR to NICRT in locally advanced ESCC, which may be valuable in personalized treatment plan optimization.

Prognostic Significance of Dynamic Lymphocyte Changes in Esophageal Cancer Patients Receiving Fluorouracil-Cisplatin Combined with Radiotherapy: A Systematic Review and Meta-Analysis

IntroductionChemoradiotherapy (CRT) is important to the esophageal cancer (EC) management. However, the predictive value of lymphocyte-related parameters, such as lymphocyte count (L), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR), is not yet fully understood. Moreover, chemotherapy agents like fluorouracil and cisplatin may have an impact on lymphocyte dynamics. This meta-analysis aims to evaluate the prognostic value of these parameters in EC patients undergoing concurrent CRT (eg, radiotherapy combined with fluorouracil and cisplatin), particularly in the context of specific chemotherapy regimens.MethodsElectronic databases were comprehensively searched up to September 2023 for research that assesses the prognostic role of lymphocyte-related indicators in EC patients undergoing CRT. Combined Hazard Ratios (HR) were estimated with a random-effects model, supplemented by meta-regression and subgroup analyses for enhanced insights.ResultsOf the 41 studies selected for qualitative evaluation, 22 were eligible for meta-analysis. These results revealed that increased pre-NLR (HR = 1.87, 95% CI = 1.55-2.26), lower pre-LMR (HR = 1.94, 95% CI = 1.36-2.77), lower dur-L (HR = 1.56, 95% CI = 1.28-1.90), and higher post-NLR (HR = 1.95, 95% CI = 1.08-3.51) predicted poorer overall survival (OS). Lower pre-LMR (HR = 1.73, 95% CI = 1.14-2.65) and lower dur-L (HR = 1.39, 95% CI = 1.14-1.69) were significant predictors of worse progression-free survival (PFS). The predominant chemotherapy regimen analyzed was fluorouracil combined with cisplatin, which significantly influenced lymphocyte counts and ratios during treatment.ConclusionsOur meta-analysis indicates that pre-treatment NLR, pre-treatment LMR, during-treatment L, and post-treatment NLR are valuable prognostic biomarkers for EC undergoing CRT, particularly in those treated with fluorouracil and cisplatin. Further investigations are warranted to explore their prognostic implications and therapeutic potential.

To develop a prognostic model for neoadjuvant immunochemotherapy efficacy in esophageal squamous cell carcinoma by analyzing the immune microenvironment

Objective

The choice of neoadjuvant therapy for esophageal squamous cell carcinoma (ESCC) is controversial. This study aims to provide a basis for clinical treatment selection by establishing a predictive model for the efficacy of neoadjuvant immunochemotherapy (NICT).

Methods

A retrospective analysis of 30 patients was conducted, divided into Response and Non-response groups based on whether they achieved major pathological remission (MPR). Differences in genes and immune microenvironment between the two groups were analyzed through next-generation sequencing (NGS) and multiplex immunofluorescence (mIF). Variables most closely related to therapeutic efficacy were selected through LASSO regression and ROC curves to establish a predictive model. An additional 48 patients were prospectively collected as a validation set to verify the model's effectiveness.

Results

NGS suggested seven differential genes (ATM, ATR, BIVM-ERCC5, MAP3K1, PRG, RBM10, and TSHR) between the two groups (P < 0.05). mIF indicated significant differences in the quantity and location of CD3+, PD-L1+, CD3+PD-L1+, CD4+PD-1+, CD4+LAG-3+, CD8+LAG-3+, LAG-3+ between the two groups before treatment (P < 0.05). Dynamic mIF analysis also indicated that CD3+, CD8+, and CD20+ all increased after treatment in both groups, with a more significant increase in CD8+ and CD20+ in the Response group (P < 0.05), and a more significant decrease in PD-L1+ (P < 0.05). The three variables most closely related to therapeutic efficacy were selected through LASSO regression and ROC curves: Tumor area PD-L1+ (AUC= 0.881), CD3+PD-L1+ (AUC= 0.833), and CD3+ (AUC= 0.826), and a predictive model was established. The model showed high performance in both the training set (AUC= 0.938) and the validation set (AUC= 0.832). Compared to the traditional CPS scoring criteria, the model showed significant improvements in accuracy (83.3% vs 70.8%), sensitivity (0.625 vs 0.312), and specificity (0.937 vs 0.906).

Conclusion

NICT treatment may exert anti-tumor effects by enriching immune cells and activating exhausted T cells. Tumor area CD3+, PD-L1+, and CD3+PD-L1+ are closely related to therapeutic efficacy. The model containing these three variables can accurately predict treatment outcomes, providing a reliable basis for the selection of neoadjuvant treatment plans.

Identification of prognostic value of anoikis-related gene score model combined with tumor microenvironment score models in esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) has poor survival. Effective prognostic models with high application value remain lack.

METHODS

Bulk RNA seq and single cell RNA-seq data were retrieved from the XENA-TCGA-ESCC cohort and GSE188900. The anoikis-related gene score (ANO score) model and tumor microenvironment score (TME score) model were constructed and merged into three subgroups. Functional annotation was analyzed by Gene Ontology terms. Univariate and multivariate Cox regression analysis, least absolute shrinkage and selection operator regression analysis and weighted gene coexpression network analysis were performed to construct prognostic prediction models and identify prognostic value. Kaplan-Meier survival curves were drawn for evaluating the overall survival (OS) of patients classified by different score subgroups. Immunotherapy response and mutation analyses were also conducted.

RESULTS

In the ANO score model, TNFSF10 was an independent factor for the prognosis of ESCC patients. The area under the curve values of the ANO-TME score model in predicting the OS were 0.638 at 5 years and 0.632 at 7 years. Patients in the ANO low score-TME high score group had a much longer OS than patients in any other ANO-TME score subgroup (p < 0.001), suggesting a higher prognostic value. The differentially expressed genes of the ANO low score-TME high score group were mainly involved in cell adhesion molecules, nucleotide excision repair, the TGF-β signaling pathway and mismatch repair. TP53 (92%), TTN (38%) and NFE2L2 (31%) were the top genes with highest mutant frequency in the ANO low score-TME high score group.

CONCLUSIONS

A novel prognostic prediction model with high application value was constructed and identified for ESCC patients, which may provide evidence for immunotherapy in the treatment of ESCC.

Predictive and prognostic markers from endoscopic ultrasound with biopsies during definitive chemoradiation therapy in esophageal squamous cell carcinoma

INTRODUCTION

Endoscopic ultrasound (EUS) may play a role in evaluating treatment response after definitive chemoradiation therapy (dCRT) for esophageal squamous cell carcinoma (ESCC). This study explored the prognostic markers of EUS with biopsies and developed two nomograms for survival prediction.

METHODS

A total of 821 patients newly diagnosed with ESCC between January 2015 and December 2019 were reviewed. We investigated the prognostic value of the changes in tumor imaging characteristics and histopathological markers by an interim response evaluation, including presence of stenosis, ulceration, tumor length, tumor thickness, lumen involvement, and tumor remission. Independent prognostic factors of progression-free survival (PFS) and overall survival (OS) were determined using Cox regression analysis and further selected to build two nomogram models for survival prediction. The receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to respectively assess its discriminatory capacity, predictive accuracy, and clinical usefulness.

RESULTS

A total of 155 patients were enrolled in this study and divided into the training (109 cases) and testing (46 cases) cohorts. Tumor length, residual tumor thickness, reduction in tumor thickness, lumen involvement, and excellent remission (ER) of spatial luminal involvement in ESCC (ER/SLI) differed significantly between responders and non-responders. For patients undergoing dCRT, tumor stage (P = 0.001, 0.002), tumor length (P = 0.013, 0.008), > 0.36 reduction in tumor thickness (P = 0.004, 0.004) and ER/SLI (P = 0.041, 0.031) were independent prognostic markers for both PFS and OS. Time-dependent ROC curves, calibration curves, and DCA indicated that the predicted survival rates of our two established nomogram models were highly accurate.

CONCLUSION

Our nomogram showed high accuracy in predicting PFS and OS for ESCC after dCRT. External validation and complementation of other biomarkers are needed in further studies.

Spatial distribution of tumor-infiltrating T cells indicated immune response status under chemoradiotherapy plus PD-1 blockade in esophageal cancer

Background

The spatial distribution of tumor-infiltrating T cells and its dynamics during chemoradiotherapy combined with PD-1 blockade is little known in esophageal squamous cell carcinoma (ESCC).

Methods

We applied the multiplex immunofluorescence method to identify T cells (CD4⁺, CD8⁺ T cells, and their PD-1^- or PD-1⁺ subsets) and myeloid-derived cells (CD11c⁺ dendritic cells, CD68⁺ macrophages, and their PD-L1⁺ subpopulations) in paired tumor biopsies (n = 36) collected at baseline and during combination (40 Gy of radiation) from a phase Ib trial (NCT03671265) of ESCC patients treated with first-line chemoradiotherapy plus anti-PD-1 antibody camrelizumab. We used the FoundationOne CDx assay to evaluate tumor mutational burden (TMB) in baseline tumor biopsies (n = 14). We dynamically assessed the nearest distance and proximity of T-cell subsets to tumor cells under combination and estimated the association between T-cell spatial distribution and combination outcome, myeloid-derived subsets, TMB, and patient baseline characteristics.

Findings

We found that the tumor compartment had lower T-cell subsets than the stromal compartment but maintained a comparable level under combination. Both before and under combination, PD-1^- T cells were located closer than PD-1⁺ T cells to tumor cells; T cells, dendritic cells, and macrophages showed the highest accumulation in the 5-10-μm distance. Higher CD4⁺ T cells in the tumor compartment and a shorter nearest distance of T-cell subsets at baseline predicted poor OS. Higher baseline CD4⁺ T cells, dendritic cells, and macrophages were associated with worse OS in less than 10-μm distance to tumor cells, but related with better OS in the farther distance. Higher on-treatment PD-1-positive-expressed CD4⁺ and CD8⁺ T cells within the 100-μm distance to tumor cells predicted longer OS. T cells, dendritic cells, and macrophages showed a positive spatial correlation. Both high TMB and smoking history were associated with a closer location of T cells to tumor cells at baseline.

Conclusions

We firstly illustrated the T-cell spatial distribution in ESCC. Combining chemoradiotherapy with PD-1 blockade could improve the antitumor immune microenvironment, which benefits the treatment outcome. Further understanding the precision spatiality of tumor-infiltrating T cells would provide new evidence for the tumor immune microenvironment and for the combination treatment with immunotherapy.

Higher radiation dose on immune cells is associated with radiation-induced lymphopenia and worse prognosis in patients with locally advanced esophageal squamous cell carcinoma

Background

To explore the effective dose to immune cells (EDIC) for better prognosis while avoiding radiation-induced lymphopenia (RIL) in patients with locally advanced esophageal squamous cell carcinoma (ESCC).

Materials and methods

Overall, 381 patients with locally advanced ESCC receiving definitive radiotherapy with or without chemotherapy (dRT ± CT) between 2014 and 2020 were included in this study. The EDIC model was calculated by radiation fraction number and mean doses to the heart, lung, and integral body. The correlation between EDIC and clinical outcomes was analyzed using Cox proportional hazards regression, and risk factors for RIL were determined by logistic regression analysis.

Results

The median EDIC was 4.38 Gy. Multivariate analysis revealed that low-EDIC significantly improved the OS of patients when compared with high-EDIC (HR = 1.614, P = 0.003) and PFS (HR = 1.401, P = 0.022). Moreover, high-EDIC was associated with a higher incidence of grade 4 RIL (OR = 2.053, P = 0.007) than low-EDIC. In addition, we identified body mass index (BMI), tumor thickness, and nodal stage as independent prognostic factors of OS and PFS, while BMI (OR = 0.576, P = 0.046) and weight loss (OR = 2.214, P = 0.005) as independent risk factors of grade 4 RIL. In subgroup analyses, the good group had better clinical outcomes than the remaining two groups (P< 0.001).

Conclusion

This study demonstrated that EDIC significantly correlates with poor clinical outcomes and severe RIL. Optimizing treatment plans to decrease the radiation doses to immune cells is critical for improving the outcomes.

The current understanding of the immune landscape relative to radiotherapy across tumor types

Radiotherapy is part of the standard of care treatment for a great majority of cancer patients. As a result of radiation, both tumor cells and the environment around them are affected directly by radiation, which mainly primes but also might limit the immune response. Multiple immune factors play a role in cancer progression and response to radiotherapy, including the immune tumor microenvironment and systemic immunity referred to as the immune landscape. A heterogeneous tumor microenvironment and the varying patient characteristics complicate the dynamic relationship between radiotherapy and this immune landscape. In this review, we will present the current overview of the immunological landscape in relation to radiotherapy in order to provide insight and encourage research to further improve cancer treatment. An investigation into the impact of radiation therapy on the immune landscape showed in several cancers a common pattern of immunological responses after radiation. Radiation leads to an upsurge in infiltrating T lymphocytes and the expression of programmed death ligand 1 (PD-L1) which can hint at a benefit for the patient when combined with immunotherapy. In spite of this, lymphopenia in the tumor microenvironment of 'cold' tumors or caused by radiation is considered to be an important obstacle to the patient's survival. In several cancers, a rise in the immunosuppressive populations is seen after radiation, mainly pro-tumoral M2 macrophages and myeloid-derived suppressor cells (MDSCs). As a final point, we will highlight how the radiation parameters themselves can influence the immune system and, therefore, be exploited to the advantage of the patient.

A retrospective study comparing definitive chemoradiotherapy vs. chemoradiotherapy followed by surgery in T4 esophageal squamous cell carcinoma patients who were downstaged after neochemoradiotherapy

Background

The outcome of patients with T4 esophageal squamous cell carcinoma (ESCC) is extremely poor. Two distinct therapeutic options are currently available for T4 esophageal cancers: neochemoradiotherapy followed by surgery (CRT-S) and definitive chemoradiotherapy (D-CRT). This study aimed to investigate the clinicopathologic characteristics of T4 ESCC in Chinese patients and compare the survival between the two therapeutic options.

Methods

We retrospectively analyzed 125 patients with clinically unresectable T4 ESCC in Tianjin Medical University Cancer Institute and Hospital from January 2010 to December 2020. Overall survival (OS), progression-free survival (PFS) and associated factors were analyzed.

Results

A total of 106 of 125 T4 ESCC patients were downstaged of the tumor by neoadjuvant CRT. Among 106 patients, 32 patients underwent CRT-S, and 74 patients underwent D-CRT. Patients in the CRT-S group had a higher OS (20.4 months vs. un-reached median OS, p = 0.037) and PFS (8.6 months vs. 21.0 months, p = 0.008) than those in the D-CRT group. In multivariate analysis, treatment was an independent predictor of PFS. After propensity score matching (PSM), 50 patients (CRT-S = 25; D-CRT = 25) were matched. Among these 50 patients, patients in the CRT-S group had a higher OS (15.6 months vs. un-reached median OS, p = 0.025) and PFS (7.2 months vs. 18.8 months, p = 0.026) than those in the D-CRT group. In multivariate analysis, treatment was an independent predictor for PFS.

Conclusion

We demonstrated that CRT-S was superior to D-CRT for T4 ESCC patients who were downstaged by neo-CRT with respect to longer OS and PFS. Randomized controlled trials involving large population samples are needed to define the standard treatment for T4 ESCC.

Definitive chemoradiotherapy versus neoadjuvant chemoradiotherapy followed by surgery in patients with locally advanced esophageal squamous cell carcinoma who achieved clinical complete response when induction chemoradiation finished: A phase II random

BACKGROUND AND PURPOSE

More than 40% of patients with esophageal squamous cell carcinoma (ESCC) exhibit pathological complete responses (pCR) after neoadjuvant chemoradiotherapy (nCRT), and theoretically, these patients may be cured by CRT and omit surgery. This prospectively randomized pilot study compared definitive chemoradiotherapy (dCRT) with nCRT in patients with locally advanced ESCC who achieved clinical complete responses (cCRs) to nCRT.

MATERIALS AND METHODS

Single center, randomized, open phase 2 study of 256 patients with locally advanced ESCC enrolled between April 2016 and November 2018. Immediately when nCRT finished, patients enrolled underwent response evaluations within 1 week. Patients with cCR were randomly allocated to undergo surgery (arm A) or complete CRT up to the definitive radiation dose (arm B). The primary end point was 3-year disease-free survival (DFS).

RESULTS

Finally, 71 patients were randomly assigned to the nCRT (n = 36) and dCRT (n = 35) arms. The median observation time was 35.7 months. The 3-year DFS rate was 56.43% in arm A versus 54.73% in arm B (hazard ratio [HR] = 0.862, 95% confidence interval [CI] = 0.452 to 1.645, P = 0.652). The 3-year overall survival (OS) rates in arms A and B were 69.5% and 62.3% (HR = 0.824, 95% CI = 403-1.688, P = 0.597), respectively.

CONCLUSIONS

According to our treatment response evaluation criteria, survival of the patients with cCR after nCRT was not significant different between nCRT group and dCRT group. An optimized response evaluation strategy soon after nCRT may guide next therapy decisions for patients with locally advanced ESCC.

Tumor Lymphocyte Infiltration Is Correlated with a Favorable Tumor Regression Grade after Neoadjuvant Treatment for Esophageal Adenocarcinoma

(1) Background: We aimed to explore the association between neoadjuvant treatment, tumor-infiltrating immune lymphocyte (TIL), and tumor-associated macrophage (TAM) and survival in patients with esophageal adenocarcinoma. (2) Methods: Patients who underwent esophagectomy were divided into three groups according to their treatment modality and tumor regression grade (TRG): (i) surgery-only group (SG), (ii) good responders (GR) group (TRG 0−1), and (iii) bad responders (BR) group (TRG 2−3). We then carried out statistical correlations of the immunofluorescence analysis of the immune infiltrate in the esophageal surgical specimens with several clinical and pathological parameters. In addition, we analyzed The Cancer Genomic Atlas (TCGA) dataset for differences in TILs, TAMs, and protein expression in immune pathways. (3) Results: Forty-three patients (SG—15, GR—13, and BR—13) were evaluated. The highest enrichment of CD3+ (p < 0.001), CD8+ (p = 0.001) and CD4+ (p = 0.009) was observed in the stroma of GR patients. On multivariate analysis, only CD8+ T cell and signet-ring features were independent prognostic factors for overall survival. In TCGA analysis, we identified overexpression of TAM and colony-stimulating factor 1 receptor (CSF-1R). (4) Conclusions: High enrichment of lymphocyte subpopulations in the microenvironment of esophageal adenocarcinoma is associated with a favorable response to neoadjuvant treatment and an improved patient outcome.

Tumor-Infiltrating Lymphocytes in Patients With Advanced Laryngeal Cancer Undergoing Bioselection

OBJECTIVE

Bioselection to assess tumor response after induction chemotherapy has been introduced as an alternative treatment strategy to total laryngectomy for patients with advanced larynx squamous cell carcinoma (LSCC). Tumor-infiltrating lymphocytes (TILs) have proven to serve as prognostic biomarkers in head and neck cancer but have not been evaluated as a way to select patients for treatment paradigms. The aim of this study is to evaluate the role of pretreatment TILs in patients with advanced LSCC undergoing the bioselection paradigm.

STUDY DESIGN

Retrospective study.

SETTING

Tertiary care hospital.

METHODS

Patients with advanced LSCC treated with bioselection and available tissue were included (N = 76). Patients were stratified into CD8-low and CD8-high cohorts by using the median TIL count. Kaplan-Meier survival analysis and multivariate cox regression were performed with SPSS version 26 (IBM).

RESULTS

After controlling for tobacco use, tumor site, and stage, a high CD8 TIL count was an independent predictor of improved 5-year disease-specific survival (hazard ratio, 0.17 [95% CI, 0.03-0.84]; P = .03). CD8 TIL counts did not predict response to induction chemotherapy; however, subgroup analysis of patients treated with chemoradiation therapy revealed that CD8 TIL count was significantly associated with degree of response (P = .012).

CONCLUSION

These findings support prior data published by our group showing that TILs are predictive of disease-specific survival in patients with head and neck cancer. CD8 TIL counts were significantly associated with degree of clinical response after induction chemotherapy. These results suggest that pretreatment assessment of tumor-infiltrating CD8 cells could be useful in selecting patients.

Spatial Distribution and Predictive Significance of Dendritic Cells and Macrophages in Esophageal Cancer Treated With Combined Chemoradiotherapy and PD-1 Blockade

Background

The first clinical study (NCT03671265) of first-line chemoradiotherapy combined with PD-1 blockade showed promising treatment outcomes in locally advanced esophageal squamous cell carcinoma (ESCC). However, partial patients did not respond to the combination treatment. The roles of dendritic cells (DCs) and macrophages in this combination treatment remain poorly understood.

Methods

We performed multiplexed immunofluorescence method to identify CD11c⁺ DCs, CD68⁺ macrophages, and their PD-L1^- or PD-L1⁺ subpopulations in paired tumor biopsies (n = 36) collected at baseline and during the combination treatment (after radiation, 40 Gy) from the phase Ib trial (NCT03671265). We applied whole exome sequencing in the baseline tumor biopsies (n = 14) to estimate tumor mutation burden (TMB). We dynamically investigated the spatial distribution of DCs and macrophages under chemoradiotherapy combined with PD-1 blockade, and evaluated the association between their spatial distribution and combination outcome, and TMB.

Results

The results showed that high percentages of PD-L1^- DCs and macrophages in the baseline tumor compartment, but not in the stromal compartment, predicted improved OS and PFS. Chemoradiotherapy combined with PD-1 blockade promoted DCs and macrophages to migrate closer to tumor cells. During combination treatment, PD-L1^- tumor cells were nearest to PD-L1^- DCs and macrophages, while PD-L1⁺ tumor cells were next to PD-L1⁺ DCs and macrophages. High TMB was closely associated with a shorter distance from tumor cells to DCs and macrophages. Shorter distance between PD-L1⁺ tumor cells and PD-L1⁺ DCs or PD-L1^- macrophages during the combination was correlated with better OS. Shorter distance between PD-L1^- tumor cells and PD-L1^- macrophages during combination was associated with both longer OS and PFS.

Conclusions

PD-L1^- or PD-L1⁺ DCs and macrophages exhibit distinct spatial distribution in ESCC. The close distance between tumor cells and these antigen-presenting cells (APCs) is critical to the clinical outcome in chemoradiotherapy combined with PD-1 blockade in ESCC patients. Our results highlight the predictive potential of spatial patterns of APCs in chemoradiotherapy combined with immunotherapy and reveal the underlying mechanism of APCs participating in chemoradiotherapy-induced antitumor immune response in ESCC.

Addition of camrelizumab to docetaxel, cisplatin, and radiation therapy in patients with locally advanced esophageal squamous cell carcinoma: a phase 1b study

Patients with locally advanced esophageal squamous cell carcinoma (ESCC) show poor survival after concurrent chemoradiotherapy. This study investigated the safety and feasibility of combining concurrent chemoradiotherapy with the anti-PD-1 antibody camrelizumab as first-line treatment for these patients. In this phase 1b study (ClinicalTrials.gov NCT03671265), patients received concurrent chemotherapy (cisplatin [25 mg/m²] plus docetaxel [25 mg/m²] for 4 weeks) and radiotherapy (2.0 Gy/fraction, total 60 Gy) with camrelizumab (200 mg every 2 weeks for 32 weeks). Primary endpoints were safety and tolerability, and health-related quality of life. Secondary endpoints were radiological and pathological response rates, overall survival (OS), and progression-free survival (PFS). Candidate biomarkers in tumor and peripheral blood were monitored at baseline and after 40 Gy radiation. Twenty patients were enrolled. The most common treatment-related grade 3 adverse events included radiation esophagitis (20%) and esophageal fistula (10%). Serious treatment-related adverse events occurred in eight (40%) patients. No treatment-related deaths were reported. Health-related quality of life did not deteriorate. Thirteen (65%) patients had an objective response after 40 Gy radiation. At a median follow-up of 23.7 months (95% CI 21.9–24.5), OS and PFS time ranged from 8.2–28.5 and 4.0–28.5 months, respectively. The 12-month and 24-month OS rate was 85.0% and 69.6%; PFS rate was 80.0% and 65.0%. Tumor PD-L1 expression and CD11c⁺ dendritic cells and peripheral-blood IL-27, IL-15, Eotaxin-3, and IL-22 were associated with OS. First-line concurrent chemoradiotherapy plus camrelizumab had a manageable safety profile and promising antitumour efficacy for ESCC, and deserves further study.

Effect of Interleukin-7 on Radiation-Induced Lymphopenia and Its Antitumor Effects in a Mouse Model

PURPOSE

Local ionizing radiation (IR) can lead to systemic lymphocyte depletion, which is associated with poor survival outcomes in patients with cancer. Interleukin-7 (IL-7) plays an important role in lymphocyte homeostasis; however, its role in alleviating radiation-induced lymphopenia remains unclear. Hence, we established a radiation-induced lymphopenia animal model and evaluated the effect of exogenous IL-7 administration.

METHODS

C3H/HeN mice underwent x-ray irradiation of 30 Gy in 10 fractions at the right hind limbs. Next, 10 mg/kg of IL-7 was injected subcutaneously, and the lymphocyte count in blood was measured. Murine hepatocellular carcinoma (HCa-1) cells were inoculated subcutaneously into the right thighs of tumor model mice, which underwent the same treatment.

RESULTS

In the naïve mouse model, the decreased CD45⁺ cell count after irradiation gradually recovered to the initial level over 3 weeks in the IR group, whereas it markedly increased to 373% of the initial level in 1 week in the IR+IL-7 group. Similar trends were observed for the CD3⁺, CD8⁺, CD4⁺, regulatory T cells, and CD19⁺ B cell counts. Similar findings were observed in the tumor mouse model. CD8⁺ and CD4⁺ T cell infiltration in tumor specimens was higher in the IL-7 and IR+IL-7 groups than in the nontreated and IR groups. Tumor growth was significantly more suppressed in the IR+IL-7 group than in the IR group. The median survival time was significantly longer in the IR+IL-7 group (not reached) than in the IR (56 days; P = .0382), IL-7 (36 days; P = .0004), or nontreated groups (36 days; P < .0001).

CONCLUSIONS

Administration of exogenous IL-7 after IR not only restored lymphocyte counts but also enhanced the antitumor effect. Exogenous IL-7 can be beneficial in overcoming radiation-induced lymphopenia and in enhancing the treatment outcome in combination with radiation therapy, which needs validation through future clinical studies.

Clonal Expansion of Tumor-Infiltrating T Cells and Analysis of the Tumor Microenvironment within Esophageal Squamous Cell Carcinoma Relapsed after Definitive Chemoradiation Therapy

(1) Background: Comparable prognoses after definitive chemoradiation therapy (CRT) to surgery alone for esophageal squamous cell carcinoma (ESCC) have been previously reported; however, no robust prognostic markers have been established. The clonality of tumor-infiltrating lymphocytes (TILs) and tumor microenvironments (TMEs) in ESCC relapsed after CRT were examined to explore prognostic markers. (2) Methods: Clonality of TIL and TME were examined in ESCC with and without preceding CRT, as well as oral squamous cell carcinoma (OSCC) and healthy volunteers as controls. The clonality of TIL was assessed by T-cell receptor (TCR) α and β repertoire analyses and evaluated by diversity indices. The TME was assessed by quantitative polymerase chain reaction evaluating PD-L1 and CD8B. (3) Results: The clonal expansion of TIL was significantly induced within ESCCs and OSCCs, when compared to healthy volunteers, and was mostly induced within ESCCs after definitive CRT. Diversity indices of TIL were not associated with the prognosis, but the ratio of PD-L1 mRNA to CD8B mRNA in TME was significantly associated with a poor prognosis after salvage surgery (p = 0.007). (4) Conclusions: The clonal expansion of TIL is induced after definitive CRT for ESCC, and the ratio of PD-L1 mRNA to CD8B mRNA within tumor tissues is a prognostic marker candidate for salvage esophagectomy after CRT.

Annual report of the esophageal cancer radiation group of the Department of Radiotherapy, Tianjin Medical University Cancer Institute & Hospital

Background

This report describes the clinical work in esophageal cancer radiation group at the Department of Radiotherapy, Tianjin Medical University Cancer Institute & Hospital (TJMUCH).

Methods

We retrospectively analyzed the clinical data of patients with esophageal cancer who received radiotherapy (RT) at TJMUCH during the 5-year period between 2015 and 2019, including RT procedures, RT methods, treatment types, treatment outcomes and complications, and clinical trials.

Results

In 2015–2019, 1,464 patients with esophageal cancer received RT at the Department of Radiotherapy, TJMUCH. Of these, 1,176 patients received definitive chemoradiotherapy (CRT), 100 received preoperative neoadjuvant CRT, 120 received postoperative adjuvant RT, 49 received post-relapse RT, and 19 received palliative RT for advanced esophageal cancer. Among the patients who received definitive CRT, the incidences of grade 2 and higher radiation esophagitis, radiation pneumonitis, and leukopenia were 19.4%, 3.6%, and 19.7%, respectively; the incidences of grade 3–4 radiation esophagitis, radiation pneumonitis, and leukopenia were 9.4%, 1.2%, and 5.4%, respectively; no grade 5 acute adverse events were observed. Esophageal fistula was the major side effect during the advanced stage of RT. In 2015–2018, 44 patients (5%, 44/846) developed esophageal fistula; of these, 34 cases occurred after RT, and 10 cases occurred during RT. The overall survival was based on the data of 544 patients with esophageal cancer who underwent definitive RT at TJMUCH between March 2010 and September 2016. The median follow-up time was 21.6 months. The median survival was 19.6 months; and the 1-, 3-, and 5-year overall survival rates were 69.4%, 37.2%, and 32.3%, respectively. In 2015-2019, approximately 201 patients participated in different prospective clinical trials.

Conclusions

RT is a crucial and effective treatment for esophageal cancer. Standardized treatment procedures, multidisciplinary cooperation, are the foundations for good treatment effects. Many promising ongoing clinical trials will be helpful to improve the prognosis and survival of esophageal cancer patients in the future.

Anti-PD-1 Immunotherapy Combined With Stereotactic Body Radiation Therapy and GM-CSF as Salvage Therapy in a PD-L1-Negative Patient With Refractory Metastatic Esophageal Squamous Cell Carcinoma: A Case Report and Literature Review

Esophageal squamous cell carcinoma (ESCC) is a malignancy with poor prognosis, which is often diagnosed at a late stage. Effective treatment options are limited when patients fail standard systemic therapy. The application of PD-1 inhibitors have led to a paradigm shift in the treatment of ESCC, but its efficacy as monotherapy is limited. Previous studies have shown that the antitumor effects may be reinforced when a PD-1 inhibitor is combined with radiotherapy or GM-CSF. This study aimed to report a case of a patient about advanced unresectable ESCC negative expression of PD-L1, who experienced tumor progression after chemoradiotherapy and targeted therapy.A significant systemic effect was seen after PD-1 inhibitor combined with GM-CSF and stereotactic body radiotherapy (SBRT) for metastatic lesions, however, severe pneumonia occurred after the triple-combination therapy. This study also reviewed several reports about the efficacy and safety of combination therapy.

Immune checkpoint inhibitors for esophageal squamous cell carcinoma: a narrative review

Esophageal cancer (EC) has the seventh highest incidence and the sixth highest mortality rate of any type of cancer worldwide. In China, esophageal squamous cell carcinoma (ESCC) accounts for more than 95% of EC patients. The main treatment for EC patients is surgery and/or chemoradiotherapy (CRT). A large proportion of EC patients are already at an advanced stage of the disease by the time they are diagnosed. In these cases, CRT is left as the only treatment choice, and the treatment outcome is poor. Immune checkpoint inhibitors (ICIs) can improve clinical response and patient survival of patient with many types of tumors through reactivating antitumor immune response. The study of ICIs in ESCC is relative delayed compared with that in other solid tumors. Recent results from clinical trials have demonstrated the safety and efficacy of ICIs either alone or combined with chemotherapy or chemoradiotherapy in ESCC patients. Accumulated evidences also have shown the improved treatment outcome was associated with PD-L1 expression, tumor DNA instability-induced tumor mutational burden (TMB), and drawing lymphocytes into the tumor. Based on these findings, ICIs combined with CRT or radiotherapy (RT) are the focus of ongoing studies. This review will summarize the recent progress in this field, especially the mechanism of ICIs used in ESCC, their clinical efficacy and toxicities, and potential biomarkers.