PDCD1 and cutaneous mastocytosis: Several lines of evidence have highlighted that immunotherapies that block immune checkpoints, such as programmed cell death 1 (PD-1)/PD-1 ligand (PD-L1) axes and cytotoxic T lymphocyte antigen-4 (CTLA-4/CD28), were related to the prognosis of CM patients (Herbreteau et al., 2018; Patel et al., 2022).