“…The common administration modality of radiation treatment is via external beam, which mainly includes stereotactic body radiotherapy (SBRT), volumetric modulated arc therapy (VMAT), intensity-modulated radiotherapy (IMRT), and image-guided intensity-modulated radiotherapy (IGRT). IGRT sometimes offers a routine procedure of position verification when patients are treated with SBRT [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] . In this case, SBRT will become the preferred choice of treatment for patients with lung cancer, especially for early-stage lung cancer.…”