Table 2. Stereotactic ratiotherapy combined with targeted therapy or immunotherapy for brain metastases of NSCLC.

Reference	Study type	Study population	Treatment	Toxicity	Intracranial response	Median overall survival
Magnuson 2017 (5)	retrospective	n = 351	– RC followed by EGFR-TKI – WBRT followed by EGFR-TKI – EGFR-TKI followed by RS or WBRT in case of intracranial progression	not reported	freedom from intracranial progression (median): RS 23 m (HR: 0.73; 95% CI: [0.52; 1.02]), WBRT 24 m (HR: 0.92 [0.66; 1.29]), EGFR-TKI: 17 m	RS: 46 m (HR: 0.39 [0.26; 0.58]),WBRT: 30 m (HR 0.70 [50%; 98%]), EGFR-TKI: 25 m
Miyawaki 2019 (6)	retrospective	n = 176	– initial EGFR-TKI – initial local therapy	not reported	freedom from intracranial progression (median): 12 m versus 22 m (HR: 0.54 [0.36; 0.79])	23 m versus 28 m (HR: 0.75 [0.52; 1.07]), subgroup with 1–4 BM: 23 m versus 35 m (HR: 0.57 [0.34; 0.91])
Lee 2019 (7)	retrospective	n = 198	– initial WBRT – initial RS – delayed RT in case of intracranial progression – no intracranial RT	not reported	freedom from intracranial progression (median): initial WBRT or RS: delayed RT or no RT: 11.7 m (p < 0.001)	initial WBRT: 18.5 m, initial RS: 55.7 m, delayed RT in case of intracranial progression: 21.1 m, no intracranial RT: 18.2 m (p = 0.008)

BM, brain metastasis (-es); EGFR, epidermal growth factor receptor; HR, hazard ratio; m, months; NSCLC, non-small-cell lung cancer;

RS, radiosurgery; RT, radiotherapy; TKI, tyrosine kinase inhibitor; WBRT, whole-brain radiation therapy; 95% CI, 95% confidence interval