EPO and anemia (phenotype): Moreover, these data support the necessity of investigating the prognostic significance of anemia in patients treated with nivolumab to understand if this condition may represent a key factor in the decision-making process between these two agents.In particular, reversible causes of anemia need to be addressed, but the data do not indicate attempting erythropoietin(EPO)-induced correction, particularly given the association of EPO with adverse outcomes in cancersin large studies [20].