Currently, the combination of photothermal conversion agents with immunotherapeutic agents, such as anti‐CTLA ‐4 antibodies,[147] anti‐PD‐1/PD‐L1 antibodies,[148] IDO inhibitors, and immune adjuvants[149] can substantially enhance immune stimulation and relieve the immunosuppressive tumor microenvironment (Table 2). Here, IDO1 is linked to neoplasm.