Comparison of efficacy and safety of combined chemoimmunotherapy with or without radiotherapy for stage IVB esophageal squamous cell carcinoma: a multicenter propensity score matching analysis.

PURPOSE: This study aimed to compare the efficacy and safety of combining first-line chemoimmunotherapy with radiotherapy versus chemoimmunotherapy alone in patients with stage IVB esophageal squamous cell carcinoma (ESCC). METHODS: We retrospectively examined 409 patients with stage IVB ESCC who received first-line chemotherapy and anti-PD-1 antibody, with or without radiotherapy of ≥ 40 Gy radiation dose to primary lesion, from four academic cancer centers between October 2018 and December 2022. Propensity score matching (PSM) was conducted to minimize the potential confounding effects. RESULTS: In the overall cohort of 409 patients, the group that received additional radiotherapy had superior overall survival (OS) (hazard ratio [HR]: 0.51, 95% confidence interval [CI]: 0.39-0.66, P < 0.001) and progression-free survival (PFS) (HR: 0.52, 95% CI: 0.40-0.66, P < 0.001) compared to the group that received chemoimmunotherapy alone. After 1:1 PSM, matching age, tumor location, and metastatic sites, a total of 250 patients were selected for further analysis. The results remained consistent and showed that the addition of radiotherapy significantly improved OS and PFS (median OS: 24.9 vs. 14.6 months, P = 0.003; median PFS: 14.2 vs. 10.6 months, P = 0.002). Multivariate Cox analysis including tumor location, T stage, metastatic sites, and treatment modality, revealed that radiotherapy was an independent prognostic factor for both OS (HR: 0.57, 95% CI: 0.41-0.81) and PFS (HR: 0.63, 95% CI: 0.47-0.86). Subgroup analyses revealed significant OS prolongation in patients with non-regional lymph node metastases only who received radiotherapy (HR: 0.49, 95% CI: 0.34-0.70). No OS survival benefit was observed in those with distant organ metastases (HR: 0.72, 95% CI: 0.46-1.13). Regarding safety, the group receiving additional radiotherapy had higher incidences of grade 3-4 lymphopenia (74.4% vs. 17.7%, P < 0.001) and esophagitis (11.2% vs. 2.4%, P = 0.006). CONCLUSION: The addition of radiotherapy to chemoimmunotherapy improved the survival of stage IVB ESCC patients with non-regional lymph nodes metastasis.

Prognostic significance of PET/CT and its association with immuno-genomic profiling in oesophageal squamous cell carcinoma treated with immunotherapy plus chemoradiotherapy: results from a phase II study.

BACKGROUND: A phase II trial (EC-CRT-001) demonstrated the promising efficacy of combining toripalimab (an anti-PD-1 antibody) with definitive chemoradiotherapy (CRT) for locally advanced oesophageal squamous cell carcinoma (ESCC). Biomarkers are key to identifying patients who may benefit from this therapeutic approach. METHODS: Of the 42 patients with ESCC who received toripalimab combined with definitive CRT, 37 were included in this analysis. Baseline assessments included PET/CT metabolic parameters (SUVmax, SUVmean, SUVpeak, MTV, and TLG), RNA sequencing of tumour biopsies to quantify the tissue mutational burden (TMB), and multiplex immunofluorescence staining to estimate immune cell infiltration in the tumour microenvironment (TME). Frozen neoplastic samples were procured for RNA sequencing to further explore the immune-related TME. RESULTS: Among the 37 patients, high baseline SUVmax (≥12.0; OR = 6.5, 95% CI 1.4-48.2, p = 0.032) and TLG (≥121.8; OR = 6.8, 95% CI 1.6-33.5, p = 0.012) were significantly correlated with lower complete response rates. All five PET/CT parameters were notably associated with overall survival; only SUVmax and TLG were associated with a significantly worse progression-free survival. A trend towards an inverse correlation was observed between SUVmax and TMB (R = -0.33, p = 0.062). PD-1 + CD8 + T cell infiltration was negatively correlated with MTV (R = -0.355, p = 0.034) and TLG (R = -0.385, p = 0.021). Moreover, RNA sequencing revealed that the high TLG subgroup exhibited low immune cell infiltration, indicating an immunosuppressive landscape. CONCLUSIONS: High baseline SUVmax and TLG might predict poorer treatment response and worse survival in patients with ESCC undergoing immunotherapy combined with CRT. In addition, high PET/CT metabolic parameters, particularly TLG, were correlated with an immunosuppressive TME, which warrants further exploration.

Predictive role of ctDNA in esophageal squamous cell carcinoma receiving definitive chemoradiotherapy combined with toripalimab.

The combination of toripalimab (an anti-PD-1 antibody) with definitive chemoradiotherapy (CRT) demonstrated encouraging efficacy against locally advanced esophageal squamous cell carcinoma (ESCC) in the EC-CRT-001 phase II trial (NCT04005170). The primary endpoint of this trial was the clinical complete response rate (cCR), and the secondary endpoints included overall survival (OS), progression-free survival (PFS), duration of response, and quality of life. The exploratory analyses of EC-CRT-001 include exploring the role of circulating tumor DNA (ctDNA) and blood-based tumor mutational burden (bTMB) in predicting the response and survival. In total, 118 blood and 35 tissue samples from 42 enrolled patients were included in the analyses. We found that ctDNA-negative patients achieved a higher cCR compared to those with detectable ctDNA during CRT (83%, 19/23 vs. 39%, 7/18; p = 0.008) or post-CRT (78%, 21/27 vs. 30%, 3/10; p = 0.017). Patients with detectable ctDNA during CRT had shorter PFS (p = 0.014). Similarly, patients with post-CRT detectable ctDNA had a significantly shorter PFS (p = 0.012) and worse OS (p = 0.004). Moreover, patients with high bTMB levels during CRT had prolonged OS (p = 0.027). In conclusion, ctDNA and bTMB have the potential to predict treatment efficacy and survival in ESCC treated with CRT and immunotherapy.

M1A and m7G modification-related genes are potential biomarkers for survival prognosis and for deciphering the tumor immune microenvironment in esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is the most common esophageal malignancy, and RNA methylation has been reported to be involved in the tumorigenesis of ESCC. However, no study has explored methylation modifications in m1A and m7G as prognostic markers for survival prediction in ESCC. METHODS: Public gene-expression data and clinical annotation of 254 patients obtained from The Cancer Genome Atlas and the Gene Expression Omnibus databases were analyzed to identify potential consensus clusters of m1A and m7G modification-related genes. The RNA-seq of 20 patients in Sun Yat-Sen University Cancer Center was used as the validation set. Following screening for relevant differentially expressed genes (DEGs) and enrichment pathways were elucidated. DEGs were used to construct risk models using the randomForest algorithm, and the prognostic role of the models was assessed by applying Kaplan-Meier analysis. Extent of immune cell infiltration, drug resistance, and response to cancer treatment among different clusters and risk groups were also evaluated. RESULTS: Consensus clustering analysis based on m1A and m7G modification patterns revealed three potential clusters. In total, 212 RNA methylation-related DEGs were identified. The methylation-associated signature consisting of 6 genes was then constructed to calculate methylation-related score (MRScore) and patients were dived into MRScore-high and MRScore-low groups. This signature has satisfied prognostic value for survival of ESCC (AUC = 0.66, 0.67, 0.64 for 2-, 3-, 4- year OS), and has satisfied performance in the validation SYSUCC cohort (AUC = 0.66 for 2- and 3-year OS). Significant correlation between m1A and m7G modification-related genes and immune cell infiltration, and drug resistance was also observed. CONCLUSIONS: Transcriptomic prognostic signatures based on m1A and m7G modification-related genes are closely associated with immune cell infiltration in ESCC patients and have important correlations with the therapeutic sensitivity of multiple chemotherapeutic agents.

Association Between Lymphopenia and Survival Outcomes in Esophageal Carcinoma Patients Receiving Combined Immunotherapy and Chemoradiotherapy.

BACKGROUND: To investigate the association between absolute lymphocyte count (ALC) nadir and survival outcomes in esophageal squamous cell carcinoma (ESCC) patients who received definitive chemoradiotherapy (CRT) combined with anti-PD-1 immunotherapy, as well as to explore clinical characteristics and dosimetric parameters that affect ALC nadir during CRT. PATIENTS AND METHODS: Patients with ESCC (n = 602) who underwent definitive CRT were analyzed, of whom 166 received combined anti-PD-1 immunotherapy and CRT. Changes in ALC and survival were compared between patients with and without immunotherapy. Propensity score matching (PSM) was performed to minimize the effects of confounding factors. Low ALC was defined as nadir of <0.33 × 103 cells/µL during CRT (top tertile). Univariate and multivariate logistic regression were used to identify predictors of low ALC nadir. RESULTS: Patients with immunotherapy had significantly higher ALC in the first 3 weeks during CRT and higher ALC nadir than those without. Overall survival was more favorable in patients with immunotherapy both before and after PSM. After a median follow-up of 12.1 months, patients with low ALC during CRT had a worse progression-free survival (PFS) (P = .026). In multivariate analysis, low ALC remained a significant prognostic factor for PFS. Planning target volume (PTV) and heart V5 were revealed to be independent predictors of low ALC. CONCLUSIONS: The addition of anti-PD-1 immunotherapy to definitive CRT could mitigate the decline of ALC during radiotherapy and might prolong survival. Low ALC nadir was correlated to worse PFS, larger PTV, and higher heart V5 in patients receiving combined immunotherapy and CRT.