AbstractBackgroundThe use of neoadjuvant immunotherapy plus chemotherapy has revolutionized the management of esophageal squamous cell carcinoma (ESCC) patients. Nevertheless, patients who would maximally benefit from these therapies have not been identified.MethodsWe collected postoperative specimens from 103 ESCC patients, of which 66 patients comprised a retrospective cohort and 37 comprised a prospective cohort. Patient specimens were subjected to applied multi‐omics analysis to uncover the mechanistic basis for patient responsiveness to cancer immunotherapy. The tumor microenvironment characteristics of these patient specimens was explored and identified by multiplex immunofluorescence and immunohistochemistry.ResultsResults demonstrated highCOL19A1expression to be a novel biomarker for successful immunotherapy (COL19A1high, odds ratio [95% confidence interval]: 0.31 [0.10–0.97],p= 0.044). Compared withCOL19A1lowpatients,COL19A1highpatients benefited more from neoadjuvant immunotherapy (p< 0.01), obtained better major pathological remissions (63.3%,p< 0.01), with a trend toward better recurrence‐free survival (p= 0.013), and overall survival (p= 0.056). Moreover, analysis of an immune‐activation subtype of patients demonstrated increased B cell infiltration to be associated with favorable patient survival and a better response to neoadjuvant immunotherapy plus chemotherapy.ConclusionsThe findings of this study provide insight into the optimal design of individual treatments for ESCC patients.