It has been reported that favorable influences of cytotoxic agents to anti-tumor immune response included immunogenic cell death and suppression of regulatory T cell and myeloid-derived suppressor cell. Some clinical trials showed that the addition of immune checkpoint inhibitor to standard chemotherapy improved efficacy in patients with non-small-cell lung cancer or malignant melanoma in first-line settings. Phase III trials of the combination of immune checkpoint inhibitor and chemotherapy in several malignancies are ongoing.