ABSTRACT
In recent years, the application of immune checkpoint inhibitors (PD-1/PD-L1/CTLA-4, etc.) in the treatment of non-small cell lung cancer (NSCLC) has developed rapidly. However, the response rate of immune checkpoint inhibitors alone is as low as 15%-30%. There are still many problems in clinical practice, such as limited benefit population, lack of effective biomarkers and treatment resistance, etc. Compared with conventional fractionated radiotherapy, stereotactic body radiation therapy (SBRT) has the characteristics of higher single dose, less irradiation times and stronger immune activation ability. It has shown good anti-tumor effect in patients with advanced NSCLC oligometastasis. The combination of immune checkpoint inhibitors and SBRT is the development trend of tumor therapy. Preclinical and clinical studies show that SBRT can enhance the efficacy of immunotherapy in patients with NSCLC. In the initial study, single-lesion SBRT was first recommended to reduce potential toxicity. However, more and more studies have confirmed the feasibility and necessity of multi-lesion SBRT. In this review, we not only elucidated the mechanism and the latest progress upon combined use of SBRT and immune checkpoint inhibitors in advanced NSCLC oligometastasis, but also explored the basic and clinical research of multi-lesion SBRT combined with immunotherapy, aiming to guide clinical practice.