Immunotherapeutics, like immune checkpoint blockade (ICB), have demonstrated therapeutic efficacy in a variety of human cancers. Even among the tumour types described as responsive, immunotherapy is only efficient in a minority of the patients. To maximise therapeutic benefits, a biomarker to identify ICB-responders is needed. Tumour mutational burden would correlate with the efficacy of immune checkpoint inhibitors. Clinical evidence for TMB as biomarker already exists in metastatic melanoma, non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC). In this review an update about tumour mutational burden (TMB) is given.

(BELG J MED ONCOL 2020;14(1):4–7)