Both the TMB and the neoantigen load have been found to predict the CPI response across a range of cancers (including colorectal and endometrial carcinoma), with high TMB (as reflected by high levels of microsatellite instability) being an established tumour-agnostic predictive biomarker for an anti-PD1 effect [33,34]. The gene discussed is PDCD1; the disease is cancer.