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.

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. This exploratory analysis evaluated the role of circulating tumor DNA (ctDNA) and blood-based tumor mutational burden (bTMB) in predicting the response and survival. We found that ctDNA-negative patients achieved a higher clinical complete response rate (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 progression-free survival (PFS) (p=0.014). Similarly, patients with post-CRT detectable ctDNA had a significantly shorter PFS (p=0.012) and worse overall survival (OS) (p=0.004). Moreover, patients with high bTMB levels during CRT had prolonged OS (p=0.027). In conclusion, ctDNA and bTMB has the potential for predicting treatment efficacy and survival in ESCC treated with CRT and immunotherapy.

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 satisfying 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.

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.