Predicting radiation-induced immune suppression in lung cancer patients treated with stereotactic body radiation therapy.

Background: Stereotactic body radiation therapy (SBRT) is known to modulate the immune system and contribute to the generation of anti-tumor T cells and stimulate T cell infiltration into tumors. Radiation-induced immune suppression (RIIS) is a side effect of radiation therapy that can decrease immunological function by killing naive T cells as well as SBRT-induced newly created effector T cells, suppressing the immune response to tumors and increasing susceptibility to infections.

Purpose: RIIS varies substantially among patients and it is currently unclear what drives this variability.