Photothermal therapy (PTT),which bums cancer under light irradiation usually using light-absorbing nano-agents,has been extensively explored as a new cancer therapeutic strategy in recent years.The immunological responses induced by nanomaterials-based PTT,however,still merit careful studies.Herein,we report that photothermal ablation of the primary tumor with single-walled carbon nanotubes (SWNTs) in combination with anti-CTLA-4 antibody therapy is able to prevent the development of tumor metastasis in mice.