Beyond tumor mutation burden: tumor neoantigen burden as a superior prognostic biomarker in resected gastric cancer

Introduction: Gastric cancer is one of the most diagnosed cancers and a major contributor to cancer-related death in China. Recent studies have demonstrated the failure of tumor mutational burden (TMB) in predictive accuracy. Here, we aimed to evaluate the prognostic value of tumor neoantigen burden (TNB) to predict the clinical outcome among patients undergoing gastric cancer resection. Methods: This study performs whole exome and transcriptome sequencing of tumor tissues of 85 gastric cancer patients who underwent resection surgery. The prognostic value of TMB and TNB in Chinese gastric cancer patients were evaluated, respectively. Results: In contrast to TMB, TNB achieved significance in predicting overall survival at both early (a median follow-up period of 23.5 month) and late (a median follow-up period of 35.5 month) timepoints (p-value