Childhood cancer is the second most common cause of death among children, and better knowledge of pediatric immunology and cancer genomics is needed to advance this field further. in this project, whole genomic sequence data of patient samples are used to explore the tumor mutation burden, HLA type, mutational signatures and their relationship with immune states across cancer types as well as in specific cancers. mRNA data of tumor tissue will also be performed to investigate immune cell infiltration, immune repertoire features, Microsatellite Instability, and neo-antigens. The project will enable better strategies for immunotherapy, tailored to children and their unique immune systems.