Studies have reported that SBRT can significantly increase the frequency of Ki67+ programmed cell death protein 1 (PD-1)+ T cells and natural killer cells in advanced tumours without a significant increase in immune checkpoints such as T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) and Lymphocyte activation gene-3 (LAG-3) (41). The gene discussed is PDCD1; the disease is neoplasm.