Figure 1. Schematic representation of the main fields of applications of MMR/MSI, PD-L1, TMB testing in patients’ selection for immunotherapy. Tumours are depicted in the columns, while the application of the test in the rows. The colour-coded circles refer to the selected testing method provided on the bottom left legend. The circles are distributed among different anatomical sites based on their clinical utility, as reported on the column placed on the left. MMR, mismatch repair; MSI, microsatellite instability; PD-L1, programmed cell death ligand 1; TMB, tumour mutational burden; IHC, immunohistochemistry; HNSCC, head and neck squamous cell carcinoma; NSCLC, non-small cell lung cancer; RCC, renal cell carcinoma.