A propensity- matched study was conducted to investigate the feasibility and safety of adding temozolomide to hypofractionated stereotactic radiotherapy for large brain metastases.

A previous single arm phase II trial of our institution has shown that HFSRT combined with concurrent TMZ was safe and efficient for patients with BMs of ≥ 6cc in volume. The 1-year local control and overall survival rate was better than the results of a retrospective study using HFSRT alone in treating BMs of ≥ 3cm in diameter. Thus, we hypothesized that adding TMZ to HFSRT should translate to substantive benefits in clinical outcomes compared to HFSRT alone. Propensity score matching method was adopted to decrease potential bias in this retrospective study.

Inclusion Criteria:

• (1) primary tumor was pathologically diagnosed and brain metastases were confirmed by gadolinium-enhanced magnetic resonance imaging (MRI) ; (2) age 18 years or older (3) KPS ≥60, or KPS ≥50 but symptomatically caused by BMs; (4) the large lesions haven't treated with surgery or SRT.

Exclusion Criteria:

• (1) KPS <60 but not caused by BMs; (2) the large lesions have been treated with surgery or SRT.

patients with large brain metastases of more than 6 cc.