CD274 and neoplasm: Several unanswered questions remain: among these, the issue of whether predictors (including treatment-related adverse events, PD-L1 expression, tumor mutational burden, gut microbiome, etc.)could be used to properly select the right patients to receive locoregional therapies plus immunotherapy and to provide useful information for disease-monitoring as well as treatment-decision making remains of pivotal importance, and these combinatorial treatments represent a promising research avenue in this setting.