FLT3LG and rectal cancer: The immune response was assessed by studying the circulating levels of the fms‐like tyrosine kinase 3 ligand (Flt3L) protein, which is a factor reflecting both therapy‐induced myelosuppression and tumor antigen‐presenting dendritic cells activation.101 Based on these considerations, several phase II clinical trials combining immune checkpoint inhibitors with CRT have been initiated for rectal cancer (NCT02586610 and NCT02948348).