Stereotactic radiation therapy (SBRT), commonly known as the X-blade, is a breakthrough and landmark treatment in the field of radiotherapy in recent years.SBRT has achieved excellent efficiency and long-term survival in early-stage non-small cell lung cancer, achieving results comparable to those of surgery. It has also achieved excellent efficacy in the treatment of advanced oligometastases. In combination with immune drugs, a synergistic treatment effect of 1+1>2 is reached. Compared with surgery, stereotactic radiation therapy is non-invasive, non-anesthetic, non-painful, and relatively less risky, making it a more appropriate treatment option for some elderly patients and early stage non-small cell lung cancer patients with underlying diseases that cannot tolerate surgery. Research on SBRT in early-stage non-small cell lung cancer In 2003, McGarry at Indiana University first reported the results of a prospective clinical study using SBRT for early-stage non-small cell lung cancer, with a 2-year control rate of 95% and an overall survival rate of 55% The results of the RTOG0236 clinical trial, published in JAMA in 2010, showed that SBRT for early-stage non-small cell The 3-year disease-free survival and overall survival rates for lung cancer were 48.3% and 55.8%, respectively, thus laying the foundation for SBRT to become the standard of care for patients with inoperable early-stage non-small cell lung cancer. 2012 National Comprehensive Cancer Network guidelines recommended SBRT as the treatment of choice for inoperable early-stage non-small cell lung cancer. In 2015, Professor Yu-Jiao Zhang of MD Anderson Cancer Center combined the results of two independent, clinical phase 3 randomized controlled studies by STARS and ROSEL to compare the efficacy of SBRT with surgical resection for patients with surgically resectable stage I non-small cell lung cancer. Fifty-nine patients were included in the study and randomly assigned to stereotactic radiotherapy and surgical treatment groups (31 and 27 patients.) Interim follow-up was 40.2 and 35.4 months for the SBRT and surgical treatment groups, respectively, with assessable 3-year survival rates of 95% and 79% and 3-year recurrence-free survival rates of 86% and 80%. The study showed that in addition to surgery, stereotactic radiotherapy is another treatment option for patients with resectable stage I lung cancer. The results of this study were published in (LancetOncol) in 2015. 2018, the American Society of Clinical Oncology also officially approved SBRT as the standard of care for early stage inoperable non-small cell lung cancer. A prospective analysis of the revisedSTARS study (revisedSTARS) was conducted by Professor Yujiao Zhang in 2021. The results of the study found that the 3- and 5-year survival rates for this group of patients were 91% and 87%, respectively, and SBRT treatment was well tolerated with no grade 4-5 toxicity, one case each of grade 3 dyspnea, grade 2 pneumonia and grade 2 pulmonary fibrosis (1%), and no serious adverse events. The 3- and 5-year OS rates for the propensity-matched lobectomy combined with mediastinal lymph node dissection cohort were 91% and 84%, respectively. Noninferiority was established because the 3-year OS rates after stereotactic radiotherapy treatment were not lower than those observed in the lobectomy combined with mediastinal lymph node dissection group. A multivariate analysis revealed no significant difference in survival rates between the two groups; 5-year lung cancer-specific survival rates were 92% and 93%, respectively (P=0.69). The study suggests that in patients with operable stage IA non-small cell lung cancer, long-term survival after SBRT is not inferior to that treated with lobectomy combined with mediastinal lymph node dissection, and that SBRT has therapeutic value for this group of patients, but multidisciplinary management of patients is strongly recommended.In April 2021, the abstract of this study was accepted and published by the American Society of Clinical Oncology (ASCO) at its annual meeting. Subsequently, in September of the same year, it was published in LancetOncol. SBRT in advanced non-small cell lung cancer with oligometastases In 2016, Gomez et al. at MD Anderson Cancer Center were the first to report the results of a phase II randomized controlled study showing that after standard first-line chemotherapy with ≤3 oligometastases, progression-free survival was significantly longer in the local treatment (SBRT or surgery) group compared to maintenance therapy or observation, with median progression-free survival of 11.93 months in the local treatment group and 11.93 months in the maintenance therapy group. The median progression-free survival was 11.93 months in the local treatment group and 3.9 months in the maintenance treatment group, with a statistically significant difference between the two groups (P=0.0054). 1-year progression-free survival was 48% in the local treatment group and 20% in the maintenance treatment group, and overall survival was 41.2 months in the local treatment group and 17.0 months in the maintenance treatment or observation group (P=0.017). All these findings show that local treatment (SBRT or surgery) of primary and metastatic sites in patients with stage IV oligometastases can prolong progression-free survival and thus achieve longer overall survival benefit. In 2018, our team was the first in the world to report a set of results regarding patients with non-small cell lung cancer EGFR-sensitive mutation oligometastases treated with local ablative therapy including SBRT primarily. It was found that among 145 patients with oligometastases from EGFR-sensitive mutations, 51 (35.2%) patients received local ablation for all primary lesions and oligometastases (All-LAT group), 55 (37.9%) patients received local ablation for some primary lesions or metastases (Part-LAT group), and 39 (26.9%) patients received local ablation for both primary lesions and metastases None of the patients received local ablation (Non-LAT group). The median progression-free survival was 20.6, 15.6, and 13.9 months in the All-LAT, Part-LAT, and Non-LAT groups, respectively (P < 0.001). Median survival was 40.9, 34.1, and 30.8 months in the All-LAT, Part-LAT, and Non-LAT groups, respectively (P < 0.001). Local ablative treatment of all sites significantly prolonged patient survival compared with local ablative treatment of some sites or no local ablative treatment, and receiving local ablative treatment with low toxic side effects is an appropriate treatment option for patients with non-small cell lung cancer oligometastases with EGFR mutations receiving EGFR-targeted therapy in the first line. In 2018, Iyengar et al. from Simmons Comprehensive Cancer Center reported a phase II randomized controlled study of patients with stage IV oligometastases treated with chemotherapy maintenance therapy versus chemotherapy maintenance therapy combined with stereotactic radiotherapy, which showed that the median PFS in the chemotherapy maintenance therapy combined with stereotactic radiotherapy group reached 9.7 months, significantly longer than the median progression-free survival in the chemotherapy maintenance therapy group ( 3.5 months) (P=0.01). A phase III randomized controlled SINADS study on first-line EGFR targeting combined with or without early aggressive local radiotherapy for EGFR mutation-positive oligometastatic non-small cell lung cancer was reported in ASCO by Wang et al. in 2020 at the Sichuan Provincial People's Hospital, and the results showed that targeted combined radiotherapy demonstrated a significant benefit over targeted therapy alone (progression-free survival: targeted combined with radiotherapy 20.2 months vs. 12.5 months in the targeted-only group, P < 001, and median survival: 25.50 months in the targeted-combination radiotherapy vs. 17.4 months in the targeted-only group, P < 001). SBRT in combination with immunotherapy in advanced non-small cell lung cancer In 2019 Bauml et al. reported a phase II study of pablizumab in patients with oligometastatic non-small cell lung cancer after stereotactic radiotherapy to assess whether the addition of pablizumab after stereotactic radiotherapy improved the prognosis of patients with oligometastatic non-small cell lung cancer. The study results showed that patients had a median progression-free survival of 19.1 months (95% CI, 9.4 to 28.7 months), which was significantly higher than the historical median of 6.6 months (P=0.005). overall survival was 90.9% at 12 months and 77.5% at 24 months. The PEMBRO-RT study in the Netherlands, published in JAMAOncol in 2019, is the first randomized, multicenter, parallel-controlled phase II clinical study comparing the impact of single metastasis body stereotactic radiation therapy with or without pablizumab efficacy prior to PD-1 treatment in advanced non-small cell lung cancer (≥2 lines). The primary endpoint was objective efficiency (at least two lesions, one measurably assessable and one suitable for local SBRT treatment). The results of the study suggested an increase in objective efficiency from 18% to 36% in the control group (P=0.07), an extension of progression-free survival from 1.9 months to 6.6 months (P=0.19), and an extension of overall survival from 7.6 months to 15.9 months (P=0.16). SBRT has become an important radical treatment for early-stage non-small cell lung cancer, especially the treatment of choice in patients who are inoperable or refuse surgery, and also plays a very important role in oligometastasis or oligoprogression of advanced non-small cell lung cancer. With the advent of China's aging society, the number of patients with early detection of lung cancer and inoperable patients will gradually increase, and the role and status of SBRT treatment will become more and more important. With the advent of the targeted and immune era, the role of SBRT in the treatment of non-small cell oligometastasis or oligoprogression is becoming more and more obvious.