Efficacy of Radiotherapy for Oligometastatic Lung Cancer and Irradiation Methods Based on Metastatic Site.

Systemic chemotherapy is a standard treatment for patients with stage IV cancer with distant metastases, and there is little evidence of the effectiveness of local treatments for distant metastatic lesions. However, in recent years, randomized phase II trials targeting oligometastases in lung cancer and solid tumors have reported that local therapy combined with systemic chemotherapy improves clinical outcomes. We reviewed previous clinical trials and demonstrated the efficacy of radiotherapy for oligometastatic disease. Stereotactic body radiotherapy (SBRT) is a promising treatment that achieves high local control rates for oligometastatic disease. Although SBRT generally does not cause severe adverse events, the safety of SBRT combined with systemic chemotherapy needs to be carefully considered. We discussed the efficacy and safety of SBRT and summarized the details of SBRT methods and techniques for each metastatic site. Further research and clinical trials are warranted to improve the efficacy of SBRT combined with systemic chemotherapy for oligometastatic non-small cell lung cancer (NSCLC).