CTLA4 and neoplasm: Two categories of biomarkers predict the response to checkpoint blockade immunotherapies: biomarkers related to tumour neoepitope burden and biomarkers indicative of a T cell–inflamed tumour microenvironment.34 The former includes microsatellite instability (MSI) and tumour mutational burden (TMB), while the latter includes the tumour inflammation signature (TIS)18 and the expression of multiple inhibitory receptors (IRs) such as programmed cell death ligand‐1 (PD‐L1) and cytotoxic T lymphocyte associated protein 4 (CTLA4).