TR accompanied with the study titled A multicenter phase II study of Nivolumab monotherapy in recurrent and/or metastatic gastrointestinal cancer patients with high Tumor Mutation Burden (TMB-H).

Primary outcome(s): 1. Evaluation of genome abnormality and gene expression by omics analysis of tumor etc. 2. TCR repertoire analysis and RNA expression analysis etc. of T cells in tumor tissue and peripheral blood. 3. Prediction and identification of tumor neo-antigen and evaluation of immunogenicity etc. 4. Analyze ctDNA(16S rRNA PCR) and feces of patients with advanced solid malignancies over time to profile and monitor cancer-related genomic alterations 5. Assessment of the relationship between the analysis above and clinical pathological features or therapeutic efficacy etc.